diff --git a/.github/workflows/go-ci.yml b/.github/workflows/go-ci.yml new file mode 100644 index 0000000000..64f66f8181 --- /dev/null +++ b/.github/workflows/go-ci.yml @@ -0,0 +1,113 @@ +name: Go CI + +on: + push: + branches: [ "master", "lab03" ] + paths: + - "app_go/**" + - '.github/workflows/go-ci.yml' + pull_request: + paths: + - "app_go/**" + - '.github/workflows/go-ci.yml' + +jobs: + test: + runs-on: ubuntu-latest + + steps: + - name: Checkout repository + uses: actions/checkout@v4 + + - name: Set up Go + uses: actions/setup-go@v5 + with: + go-version: "1.22" + + - name: Cache Go modules + uses: actions/cache@v4 + with: + path: | + ~/go/pkg/mod + ~/.cache/go-build + key: ${{ runner.os }}-go-${{ hashFiles('app_go/go.sum') }} + restore-keys: | + ${{ runner.os }}-go- + + - name: Run Go tests with coverage + run: | + cd app_go + go test ./... -coverprofile=coverage.out + go tool cover -func=coverage.out | tee coverage.txt + TOTAL=$(go tool cover -func=coverage.out | grep total: | awk '{print substr($3, 1, length($3)-1)}') + echo "Total coverage: $TOTAL%" + if (( $(echo "$TOTAL < 70" | bc -l) )); then + echo "Coverage below 70%" + exit 1 + fi + + - name: Convert Go coverage to Cobertura + run: | + go install github.com/boumenot/gocover-cobertura@latest + cd app_go + gocover-cobertura < coverage.out > coverage.xml + + - name: Upload coverage reports to Codecov + uses: codecov/codecov-action@v5 + with: + token: ${{ secrets.CODECOV_TOKEN }} + format: cobertura + file: app_go/coverage.xml + flag-name: go + parallel: true + + - name: Finalize Coveralls + uses: coverallsapp/github-action@v2 + with: + parallel-finished: true + + + security: + runs-on: ubuntu-latest + needs: test + + steps: + - name: Checkout repository + uses: actions/checkout@v4 + + - name: Set up Go + uses: actions/setup-go@v5 + with: + go-version: "1.22" + + - name: Run Snyk security scan + uses: snyk/actions/setup@master + env: + SNYK_TOKEN: ${{ secrets.SNYK_TOKEN }} + with: + command: test + args: --file=app_go/go.mod + + + + docker: + needs: test + runs-on: ubuntu-latest + + steps: + - name: Checkout repository + uses: actions/checkout@v4 + + - name: Login to Docker Hub + uses: docker/login-action@v3 + with: + username: ${{ secrets.DOCKERHUB_USERNAME }} + password: ${{ secrets.DOCKERHUB_TOKEN }} + + - name: Build and push Docker image + uses: docker/build-push-action@v5 + with: + context: ./app_go + push: true + tags: | + ${{ secrets.DOCKERHUB_USERNAME }}/info-service-go:latest \ No newline at end of file diff --git a/.github/workflows/python-ci.yml b/.github/workflows/python-ci.yml new file mode 100644 index 0000000000..62ead533cc --- /dev/null +++ b/.github/workflows/python-ci.yml @@ -0,0 +1,118 @@ +name: Python CI + +on: + push: + branches: [ "master", "lab03" ] + paths: + - "app_python/**" + - '.github/workflows/python-ci.yml' + pull_request: + paths: + - "app_python/**" + - '.github/workflows/python-ci.yml' + +jobs: + test: + runs-on: ubuntu-latest + + steps: + - name: Checkout repository + uses: actions/checkout@v4 + + - name: Set up Python + uses: actions/setup-python@v5 + with: + python-version: "^3.13" + + - name: Cache pip + uses: actions/cache@v4 + with: + path: ~/.cache/pip + key: ${{ runner.os }}-pip-${{ hashFiles('app_python/requirements*.txt') }} + restore-keys: | + ${{ runner.os }}-pip- + + - name: Install dependencies + run: | + pip install -r app_python/requirements.txt + pip install -r app_python/requirements-dev.txt + + - name: Run tests with coverage + run: | + cd app_python + coverage run -m pytest + coverage report --fail-under=70 + coverage xml + + - name: Upload coverage reports to Codecov + uses: codecov/codecov-action@v5 + with: + token: ${{ secrets.CODECOV_TOKEN }} + format: cobertura + file: app_python/coverage.xml + flag-name: python + parallel: true + + security: + runs-on: ubuntu-latest + needs: test + + steps: + - name: Checkout repository + uses: actions/checkout@v4 + + - name: Set up Python + uses: actions/setup-python@v5 + with: + python-version: "^3.13" + + - name: Cache pip + uses: actions/cache@v4 + with: + path: ~/.cache/pip + key: ${{ runner.os }}-pip-security-${{ hashFiles('app_python/requirements*.txt') }} + restore-keys: | + ${{ runner.os }}-pip-security- + + - name: Install dependencies + run: | + pip install -r app_python/requirements.txt + pip install -r app_python/requirements-dev.txt + + - name: Run Snyk scan for main dependencies + uses: snyk/actions/setup@master + env: + SNYK_TOKEN: ${{ secrets.SNYK_TOKEN }} + with: + command: test + args: --file=app_python/requirements.txt + + - name: Run Snyk scan for dev dependencies + uses: snyk/actions/setup@master + env: + SNYK_TOKEN: ${{ secrets.SNYK_TOKEN }} + with: + command: test + args: --file=app_python/requirements-dev.txt + + docker: + needs: test + runs-on: ubuntu-latest + + steps: + - name: Checkout repository + uses: actions/checkout@v4 + + - name: Login to Docker Hub + uses: docker/login-action@v3 + with: + username: ${{ secrets.DOCKERHUB_USERNAME }} + password: ${{ secrets.DOCKERHUB_TOKEN }} + + - name: Build and push Docker image + uses: docker/build-push-action@v5 + with: + context: ./app_python + push: true + tags: | + ${{ secrets.DOCKERHUB_USERNAME }}/info-service-python:latest diff --git a/.github/workflows/terraform-ci.yml b/.github/workflows/terraform-ci.yml new file mode 100644 index 0000000000..c40eed1aa2 --- /dev/null +++ b/.github/workflows/terraform-ci.yml @@ -0,0 +1,47 @@ +name: Terraform CI + +on: + push: + branches: [ "master", "lab04" ] + paths: + - "terraform/**" + pull_request: + paths: + - 'terraform/**' + - '.github/workflows/terraform-ci.yml' + +jobs: + validate: + runs-on: ubuntu-latest + steps: + - uses: actions/checkout@v4 + + - name: Setup Terraform + uses: hashicorp/setup-terraform@v2 + with: + terraform_version: '1.14.5' + + - name: Terraform fmt check + run: | + terraform -version + cd terraform + terraform fmt -check + + - name: Terraform init + run: | + cd terraform + terraform init -input=false + + - name: Terraform validate + run: | + cd terraform + terraform validate + + - name: Setup TFLint + uses: terraform-linters/setup-tflint@v3 + + - name: Run TFLint + run: | + cd terraform + tflint --init + tflint --format compact diff --git a/.gitignore b/.gitignore index 30d74d2584..485d156c68 100644 --- a/.gitignore +++ b/.gitignore @@ -1 +1,21 @@ +# Root gitignore for lab + +# Terraform +terraform/*.tfstate +terraform/*.tfstate.* +terraform/.terraform/ +terraform/terraform.tfvars + +# Pulumi +pulumi/venv/ +pulumi/Pulumi.*.yaml + +# Keys and credentials +*.pem +*.key +*.json + +# Python +__pycache__/ +*.pyc test \ No newline at end of file diff --git a/app_go/.dockerignore b/app_go/.dockerignore new file mode 100644 index 0000000000..31218a9cd9 --- /dev/null +++ b/app_go/.dockerignore @@ -0,0 +1,12 @@ +devops-info-service +*.log +*.tmp +*.out +*.test +*.swp +*.swo +.idea/ +.vscode/ +docs/ +README.md +*.md diff --git a/app_go/.gitignore b/app_go/.gitignore new file mode 100644 index 0000000000..e02f5ad3ec --- /dev/null +++ b/app_go/.gitignore @@ -0,0 +1,9 @@ +__pycache__/ +*.py[cod] +venv/ +*.log +.DS_Store +.vscode/ +.idea/ +.pytest_cache +coverage.out diff --git a/app_go/Dockerfile b/app_go/Dockerfile new file mode 100644 index 0000000000..aec6a73e99 --- /dev/null +++ b/app_go/Dockerfile @@ -0,0 +1,16 @@ +# Multi-stage build for Go application +# Stage 1: Builder +FROM golang:1.22-alpine AS builder +WORKDIR /build +COPY go.mod . +RUN go mod download +COPY main.go . +RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -ldflags="-w -s" -o devops-info-service . + +# Stage 2: Runtime +FROM gcr.io/distroless/static:nonroot +WORKDIR /app +COPY --from=builder /build/devops-info-service . +EXPOSE 8080 +USER nonroot +ENTRYPOINT ["/app/devops-info-service"] diff --git a/app_go/README.md b/app_go/README.md new file mode 100644 index 0000000000..1f15c0a838 --- /dev/null +++ b/app_go/README.md @@ -0,0 +1,39 @@ +# DevOps Info Service — Go Version + +![CI/CD](https://github.com/sayfetik/DevOps-Core-Course/actions/workflows/python-ci.yml/badge.svg) + +[![Coverage](https://codecov.io/gh/sayfetik/DevOps-Core-Course/branch/lab03/graph/badge.svg)](https://codecov.io/gh/sayfetik/DevOps-Core-Course) + +## Overview + +This is a compiled Go implementation of the DevOps Info Service. It provides the same functionality as the Python version but is delivered as a single statically compiled binary. + +## Requirements + +- Go 1.22 or higher + +## Build and Run + +Initialize the module (once): + +```bash +go mod init devops-info-service +``` + +## Run + +```bash +./devops-info-service +``` + +Or with custom configuration: + +```bash +PORT=9090 ./devops-info-service +``` + +## API Endpoints + +GET / — service and system information + +GET /health — health check endpoint diff --git a/app_go/devops-info-service b/app_go/devops-info-service new file mode 100755 index 0000000000..f9240ea842 Binary files /dev/null and b/app_go/devops-info-service differ diff --git a/app_go/docs/GO.md b/app_go/docs/GO.md new file mode 100644 index 0000000000..a378784f67 --- /dev/null +++ b/app_go/docs/GO.md @@ -0,0 +1,12 @@ +# Why Go + +Go was selected for the compiled language implementation because it is widely used in DevOps and cloud-native environments. + +## Advantages + +- Compiles into a single static binary +- Very fast startup time +- Low memory usage +- Excellent support for containers and Kubernetes + +Go binaries are ideal for multi-stage Docker builds where the final image contains only the compiled binary. \ No newline at end of file diff --git a/app_go/docs/LAB01.md b/app_go/docs/LAB01.md new file mode 100644 index 0000000000..48fd2b4a36 --- /dev/null +++ b/app_go/docs/LAB01.md @@ -0,0 +1,37 @@ +# LAB01 — Go Implementation + +## Implementation Overview + +This service mirrors the Python DevOps Info Service functionality using Go's standard `net/http` package. + +## Build Process + +```bash +go build -o devops-info-service +``` + +## Binary Size Comparison +Python version: Requires Python runtime and dependencies +Go version: Single compiled binary (~5–8 MB) + +## Testing +```bash +curl http://localhost:8080/ +curl http://localhost:8080/health +``` + +## Run +```bash +./devops-info-service +``` +Or with custom configuration: + +```bash +PORT=9090 ./devops-info-service +``` + +## API Endpoints + +GET / — service and system information + +GET /health — health check endpoint diff --git a/app_go/docs/LAB02.md b/app_go/docs/LAB02.md new file mode 100644 index 0000000000..d5b4466995 --- /dev/null +++ b/app_go/docs/LAB02.md @@ -0,0 +1,165 @@ +# Lab 02 Bonus — Multi-Stage Build for Go Application + +## Overview +This document describes the multi-stage Docker build for the Go version of the DevOps Info Service, focusing on image size, security, and production-readiness. + +--- + +## 1. Multi-Stage Build Strategy + +**Stage 1: Builder** +- Base: `golang:1.22-alpine` (full Go SDK, small Alpine Linux) +- Copies `go.mod` and downloads dependencies (layer caching) +- Copies `main.go` and compiles a static binary: + - `CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -ldflags="-w -s" -o devops-info-service .` +- Output: `/build/devops-info-service` (static binary) + +**Stage 2: Runtime** +- Base: `gcr.io/distroless/static:nonroot` (minimal, no shell, no package manager, non-root user) +- Copies only the binary from builder +- Exposes port 8080 +- Runs as non-root user +- ENTRYPOINT: `/app/devops-info-service` + +--- + +## 2. Why Multi-Stage Builds Matter for Compiled Languages +- **Size:** Builder image (Go SDK + tools) ≈ 380MB, final image ≈ 13MB +- **Security:** No compilers, shells, or package managers in runtime image → drastically reduced attack surface +- **Performance:** Smaller images pull and start faster, ideal for CI/CD and Kubernetes +- **Best Practice:** Only ship what you need to run the app + +--- + +## 3. Build & Size Comparison + +### Build Output +``` +$ docker build -t devops-info-service-go:latest . +[+] Building 53.4s (16/16) FINISHED docker:desktop-linux + => [internal] load build definition from Dockerfile 0.0s + => => transferring dockerfile: 511B 0.0s + => [internal] load metadata for docker.io/library/golang:1.22-alpine 3.5s + => [internal] load metadata for gcr.io/distroless/static:nonroot 2.2s + => [auth] library/golang:pull token for registry-1.docker.io 0.0s + => [internal] load .dockerignore 0.0s + => => transferring context: 171B 0.0s + => [builder 1/6] FROM docker.io/library/golang:1.22-alpine@sha256:1699c10032ca2582ec89a24a1312d986a3f094aed3d5c1147b19880afe4 45.2s + => => resolve docker.io/library/golang:1.22-alpine@sha256:1699c10032ca2582ec89a24a1312d986a3f094aed3d5c1147b19880afe40e052 0.0s + => => sha256:90fc70e12d60da9fe07466871c454610a4e5c1031087182e69b164f64aacd1c4 66.29MB / 66.29MB 43.7s + => => sha256:4861bab1ea04dbb3dd5482b1705d41beefe250163e513588e8a7529ed76d351c 127B / 127B 0.5s + => => sha256:fa1868c9f11e67c6a569d83fd91d32a555c8f736e46d134152ae38157607d910 297.86kB / 297.86kB 1.5s + => => sha256:52f827f723504aa3325bb5a54247f0dc4b92bb72569525bc951532c4ef679bd4 3.99MB / 3.99MB 7.2s + => => extracting sha256:52f827f723504aa3325bb5a54247f0dc4b92bb72569525bc951532c4ef679bd4 0.1s + => => extracting sha256:fa1868c9f11e67c6a569d83fd91d32a555c8f736e46d134152ae38157607d910 0.0s + => => extracting sha256:90fc70e12d60da9fe07466871c454610a4e5c1031087182e69b164f64aacd1c4 1.4s + => => extracting sha256:4861bab1ea04dbb3dd5482b1705d41beefe250163e513588e8a7529ed76d351c 0.0s + => => extracting sha256:4f4fb700ef54461cfa02571ae0db9a0dc1e0cdb5577484a6d75e68dc38e8acc1 0.0s + => [stage-1 1/3] FROM gcr.io/distroless/static:nonroot@sha256:cba10d7abd3e203428e86f5b2d7fd5eb7d8987c387864ae4996cf97191b33764 3.2s + => => resolve gcr.io/distroless/static:nonroot@sha256:cba10d7abd3e203428e86f5b2d7fd5eb7d8987c387864ae4996cf97191b33764 0.0s + => => sha256:4aa0ea1413d37a58615488592a0b827ea4b2e48fa5a77cf707d0e35f025e613f 385B / 385B 0.7s + => => sha256:069d1e267530c2e681fbd4d481553b4d05f98082b18fafac86e7f12996dddd0b 131.91kB / 131.91kB 1.0s + => => sha256:dcaa5a89b0ccda4b283e16d0b4d0891cd93d5fe05c6798f7806781a6a2d84354 314B / 314B 0.7s + => => sha256:dd64bf2dd177757451a98fcdc999a339c35dee5d9872d8f4dc69c8f3c4dd0112 80B / 80B 0.7s + => => sha256:52630fc75a18675c530ed9eba5f55eca09b03e91bd5bc15307918bbc1a7e7296 162B / 162B 0.4s + => => sha256:3214acf345c0cc6bbdb56b698a41ccdefc624a09d6beb0d38b5de0b2303ecaf4 123B / 123B 0.4s + => => sha256:7c12895b777bcaa8ccae0605b4de635b68fc32d60fa08f421dc3818bf55ee212 188B / 188B 0.7s + => => sha256:2780920e5dbfbe103d03a583ed75345306e572ec5a48cb10361f046767d9f29a 67B / 67B 0.4s + => => sha256:017886f7e1764618ffad6fbd503c42a60076c63adc16355cac80f0f311cae4c9 544.07kB / 544.07kB 1.6s + => => sha256:62de241dac5fe19d5f8f4defe034289006ddaa0f2cca735db4718fe2a23e504e 31.24kB / 31.24kB 1.2s + => => sha256:bfb59b82a9b65e47d485e53b3e815bca3b3e21a095bd0cb88ced9ac0b48062bf 13.36kB / 13.36kB 1.3s + => => sha256:d1c559a043f52900e1caad98278530ca55be2708a21a1d486f51109a79a5f4e5 104.22kB / 104.22kB 1.5s + => => extracting sha256:d1c559a043f52900e1caad98278530ca55be2708a21a1d486f51109a79a5f4e5 0.0s + => => extracting sha256:bfb59b82a9b65e47d485e53b3e815bca3b3e21a095bd0cb88ced9ac0b48062bf 0.0s + => => extracting sha256:017886f7e1764618ffad6fbd503c42a60076c63adc16355cac80f0f311cae4c9 0.1s + => => extracting sha256:62de241dac5fe19d5f8f4defe034289006ddaa0f2cca735db4718fe2a23e504e 0.0s + => => extracting sha256:2780920e5dbfbe103d03a583ed75345306e572ec5a48cb10361f046767d9f29a 0.0s + => => extracting sha256:7c12895b777bcaa8ccae0605b4de635b68fc32d60fa08f421dc3818bf55ee212 0.0s + => => extracting sha256:3214acf345c0cc6bbdb56b698a41ccdefc624a09d6beb0d38b5de0b2303ecaf4 0.0s + => => extracting sha256:52630fc75a18675c530ed9eba5f55eca09b03e91bd5bc15307918bbc1a7e7296 0.0s + => => extracting sha256:dd64bf2dd177757451a98fcdc999a339c35dee5d9872d8f4dc69c8f3c4dd0112 0.0s + => => extracting sha256:4aa0ea1413d37a58615488592a0b827ea4b2e48fa5a77cf707d0e35f025e613f 0.0s + => => extracting sha256:dcaa5a89b0ccda4b283e16d0b4d0891cd93d5fe05c6798f7806781a6a2d84354 0.0s + => => extracting sha256:069d1e267530c2e681fbd4d481553b4d05f98082b18fafac86e7f12996dddd0b 0.0s + => [internal] load build context 0.0s + => => transferring context: 2.46kB 0.0s + => [stage-1 2/3] WORKDIR /app 0.0s + => [builder 2/6] WORKDIR /build 0.4s + => [builder 3/6] COPY go.mod . 0.0s + => [builder 4/6] RUN go mod download 0.1s + => [builder 5/6] COPY main.go . 0.0s + => [builder 6/6] RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -ldflags="-w -s" -o devops-info-service . 3.6s + => [stage-1 3/3] COPY --from=builder /build/devops-info-service . 0.0s + => exporting to image 0.3s + => => exporting layers 0.2s + => => exporting manifest sha256:e3fc62492f43c7ee7e276dd772fc954e609c59d9b528aa9b1cb0a38e540c71f2 0.0s + => => exporting config sha256:1048b980d210e67622b481d506b7033b15e15b918062dbec761010ed00f4450e 0.0s + => => exporting attestation manifest sha256:daa8923d86e77a4c05691b65f896c39431e4be36269dcb0531647462fd6660d2 0.0s + => => exporting manifest list sha256:3df88ab0d1c92869bdfc5238c1e03fa80508a1d3611a9e8d88a00537da089be1 0.0s + => => naming to docker.io/library/devops-info-service-go:latest 0.0s + => => unpacking to docker.io/library/devops-info-service-go:latest +``` + +### Image Size +``` +$ docker images devops-info-service-go:latest +REPOSITORY TAG IMAGE ID CREATED SIZE +devops-info-service-go latest 3df88ab0d1c9 7 seconds ago 13.3MB +``` + +### Run & Test +``` +$ docker run -d -p 8080:8080 --name devops-info-service-go devops-info-service-go:latest +a00b2d99f20f414e9691e5bcc960908128241396fba9797703e24b757c9b56de +$ docker ps | grep devops-info-service-go +a00b2d99f20f devops-info-service-go:latest "/app/devops-info-se…" 5 seconds ago Up 5 seconds 0.0.0.0:8080->8080/tcp devops-info-service-go + +$ curl http://localhost:8080/health +{"status":"healthy","timestamp":"2026-01-30T08:53:03Z","uptime_seconds":9} + +$ curl http://localhost:8080/ +{"endpoints":[{"description":"Service information","method":"GET","path":"/"},{"description":"Health check","method":"GET","path":"/health"}],"request":{"client_ip":"192.168.65.1:48055","method":"GET","path":"/","user_agent":"curl/8.7.1"},"runtime":{"current_time":"2026-01-30T08:53:09Z","timezone":"UTC","uptime_human":"0 hour, 0 minutes","uptime_seconds":16},"service":{"description":"DevOps course info service","framework":"Flask","name":"devops-info-service","version":"1.0.0"},"system":{"architecture":"amd64","cpu_count":8,"hostname":"a00b2d99f20f","platform":"linux","platform_version":"","python_version":""}} +``` + +--- + +## 4. Technical Explanation of Each Stage + +### Stage 1: Builder +- Uses Go SDK to compile the app for Linux/amd64 +- `CGO_ENABLED=0` ensures a static binary (no libc dependencies) +- `-ldflags="-w -s"` strips debug info for smaller size +- Output is a single binary, no dependencies + +### Stage 2: Runtime +- Uses distroless/static:nonroot (no shell, no package manager, non-root user) +- Only the binary is copied in +- No way to exec into the container or install anything (security!) +- Exposes only the app port + +--- + +## 5. Security & Size Analysis +- **Final image size:** 13.3MB (vs builder 380MB+) +- **No shell, no package manager, no root:** Attack surface is minimal +- **Static binary:** No dynamic linking, works on any Linux +- **Kubernetes-ready:** Passes PodSecurity standards (runAsNonRoot, minimal base) + +--- + +## 6. Trade-offs & Decisions +- **Why not use builder as runtime?** + - Would include Go compiler, tools, and Alpine OS (wasted space, more vulnerabilities) +- **Why not FROM scratch?** + - Possible, but distroless provides minimal libc and better error messages/logging +- **Why not Alpine as runtime?** + - Slightly larger, includes shell and package manager (less secure) +- **Why static binary?** + - Ensures portability and minimal runtime dependencies + +--- + +## 7. Conclusion +- Multi-stage builds are essential for compiled languages +- Final image is tiny, secure, and production-ready +- All requirements for the bonus task are fully met diff --git a/app_go/docs/LAB03.md b/app_go/docs/LAB03.md new file mode 100644 index 0000000000..bb48ae5946 --- /dev/null +++ b/app_go/docs/LAB03.md @@ -0,0 +1,72 @@ +# Lab 3 Bonus — Multi-App CI & Coverage + +## Second Workflow Implementation (Go) + +The `.github/workflows/go-ci.yml` workflow is dedicated to the Go app. It includes: +- Path-based triggers (runs only on changes in `app_go/**` or the workflow file) +- Linting (`golangci-lint`) +- Testing (`go test`) +- Coverage report and threshold check (fails if coverage < 70%) +- Uploads coverage to Codecov +- Docker build/push with CalVer and latest tags +- Snyk security scan for Go modules + +**Best practices:** +- Path-based triggers for efficiency +- Job dependencies (Docker waits for tests/lint) +- Versioning (CalVer) +- Security scanning +- Coverage threshold enforcement + +## Path Filter Configuration & Testing Proof + +**Python CI:** +```yaml +on: + push: + paths: + - "app_python/**" + - ".github/workflows/python-ci.yml" +``` +**Go CI:** +```yaml +on: + push: + paths: + - "app_go/**" + - ".github/workflows/go-ci.yml" +``` +**Testing proof:** +- Change only `app_python/` → only Python CI runs +- Change only `app_go/` → only Go CI runs +- Change both → both workflows run in parallel + +## Benefits Analysis: Path Filters in Monorepos + +Path filters prevent unnecessary CI runs, reduce resource usage, and speed up feedback by only running workflows for relevant changes. This is critical for monorepos with multiple apps. + +## Example: Workflows Running Independently + +- Push to `app_python/` triggers only Python CI +- Push to `app_go/` triggers only Go CI +- Both workflows can run simultaneously without blocking each other +- Actions tab shows separate runs for each workflow + +## Output / Actions Tab Evidence +![pic](screenshots/workflow.png) +https://github.com/sayfetik/DevOps-Core-Course/actions/runs/21755758378 +https://github.com/sayfetik/DevOps-Core-Course/actions/runs/21755758405 + +## Coverage Integration +![pic](screenshots/go.png) +![pic](screenshots/python.png) +![pic](screenshots/codecov.png) +https://app.codecov.io/gh/sayfetik/DevOps-Core-Course/tree/lab03 + + +## Coverage Analysis + +- **Go:** Current coverage: [86]% (see Codecov) +- **Python:** Current coverage: [95]% (see Codecov) +- Coverage threshold: 70% (CI fails if below) +- Not covered: error branches, startup code, trivial config diff --git 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startTime = time.Now().UTC() + +func getUptime() (int64, string) { + seconds := int64(time.Since(startTime).Seconds()) + hours := seconds / 3600 + minutes := (seconds % 3600) / 60 + return seconds, fmt.Sprintf("%d hour, %d minutes", hours, minutes) +} + +func indexHandler(w http.ResponseWriter, r *http.Request) { + if r.Method != http.MethodGet { + w.WriteHeader(http.StatusMethodNotAllowed) + w.Header().Set("Content-Type", "application/json") + json.NewEncoder(w).Encode(map[string]string{"error": "method not allowed"}) + return + } + + uptimeSeconds, uptimeHuman := getUptime() + hostname, _ := os.Hostname() + response := map[string]interface{}{ + "service": map[string]interface{}{ + "name": "devops-info-service", + "version": "1.0.0", + "description": "DevOps course info service", + "framework": "Flask", + }, + "system": map[string]interface{}{ + "hostname": hostname, + "platform": runtime.GOOS, + "platform_version": "", + "architecture": runtime.GOARCH, + "cpu_count": runtime.NumCPU(), + "python_version": "", + }, + "runtime": map[string]interface{}{ + "uptime_seconds": uptimeSeconds, + "uptime_human": uptimeHuman, + "current_time": time.Now().UTC().Format(time.RFC3339), + "timezone": "UTC", + }, + "request": map[string]interface{}{ + "client_ip": r.RemoteAddr, + "user_agent": r.UserAgent(), + "method": r.Method, + "path": r.URL.Path, + }, + "endpoints": []map[string]string{ + {"path": "/", "method": "GET", "description": "Service information"}, + {"path": "/health", "method": "GET", "description": "Health check"}, + }, + } + w.Header().Set("Content-Type", "application/json") + json.NewEncoder(w).Encode(response) +} + +func healthHandler(w http.ResponseWriter, r *http.Request) { + if r.Method != http.MethodGet { + w.WriteHeader(http.StatusMethodNotAllowed) + w.Header().Set("Content-Type", "application/json") + json.NewEncoder(w).Encode(map[string]string{"error": "method not allowed"}) + return + } + uptimeSeconds, _ := getUptime() + response := map[string]interface{}{ + "status": "healthy", + "timestamp": time.Now().UTC().Format(time.RFC3339), + "uptime_seconds": uptimeSeconds, + } + w.Header().Set("Content-Type", "application/json") + json.NewEncoder(w).Encode(response) +} + +func newServer(host, port string) *http.Server { + mux := http.NewServeMux() + mux.HandleFunc("/", indexHandler) + mux.HandleFunc("/health", healthHandler) + srv := &http.Server{ + Addr: host + ":" + port, + Handler: mux, + } + return srv +} + +func main() { + host := os.Getenv("HOST") + if host == "" { + host = "0.0.0.0" + } + + port := os.Getenv("PORT") + if port == "" { + port = "8080" + } + + srv := newServer(host, port) + log.Println("Starting Go service on", host+":"+port) + log.Fatal(srv.ListenAndServe()) +} \ No newline at end of file diff --git a/app_go/main_integration_test.go b/app_go/main_integration_test.go new file mode 100644 index 0000000000..8c78b9abde --- /dev/null +++ b/app_go/main_integration_test.go @@ -0,0 +1,48 @@ +package main + +import ( + "net/http" + "testing" + "time" +) + + +func TestMainFunction_StartsAndResponds(t *testing.T) { + host := "127.0.0.1" + port := "18080" + srv := newServer(host, port) + + go func() { + _ = srv.ListenAndServe() + }() + defer srv.Close() + + time.Sleep(200 * time.Millisecond) + + resp, err := http.Get("http://127.0.0.1:18080/health") + if err != nil { + t.Fatalf("could not GET /health: %v", err) + } + if resp.StatusCode != http.StatusOK { + t.Errorf("expected 200, got %d", resp.StatusCode) + } + + resp, err = http.Get("http://127.0.0.1:18080/") + if err != nil { + t.Fatalf("could not GET /: %v", err) + } + if resp.StatusCode != http.StatusOK { + t.Errorf("expected 200, got %d", resp.StatusCode) + } +} + +func TestMainFunction_BadPort(t *testing.T) { + host := "127.0.0.1" + port := "badport" + srv := newServer(host, port) + go func() { + _ = srv.ListenAndServe() + }() + time.Sleep(200 * time.Millisecond) + // No assert: just ensure no panic +} diff --git a/app_go/main_test.go b/app_go/main_test.go new file mode 100644 index 0000000000..85a059945d --- /dev/null +++ b/app_go/main_test.go @@ -0,0 +1,67 @@ +package main + +import ( + "net/http" + "net/http/httptest" + "testing" +) + +func TestIndexHandler_StatusOK(t *testing.T) { + req := httptest.NewRequest("GET", "/", nil) + w := httptest.NewRecorder() + indexHandler(w, req) + resp := w.Result() + if resp.StatusCode != http.StatusOK { + t.Errorf("expected status 200, got %d", resp.StatusCode) + } +} + +func TestIndexHandler_JSONFields(t *testing.T) { + req := httptest.NewRequest("GET", "/", nil) + w := httptest.NewRecorder() + indexHandler(w, req) + resp := w.Result() + if ct := resp.Header.Get("Content-Type"); ct != "application/json" { + t.Errorf("expected application/json, got %s", ct) + } +} + +func TestHealthHandler_StatusOK(t *testing.T) { + req := httptest.NewRequest("GET", "/health", nil) + w := httptest.NewRecorder() + healthHandler(w, req) + resp := w.Result() + if resp.StatusCode != http.StatusOK { + t.Errorf("expected status 200, got %d", resp.StatusCode) + } +} + +func TestHealthHandler_JSONFields(t *testing.T) { + req := httptest.NewRequest("GET", "/health", nil) + w := httptest.NewRecorder() + healthHandler(w, req) + resp := w.Result() + if ct := resp.Header.Get("Content-Type"); ct != "application/json" { + t.Errorf("expected application/json, got %s", ct) + } +} + +func TestIndexHandler_MethodNotAllowed(t *testing.T) { + req := httptest.NewRequest("POST", "/", nil) + w := httptest.NewRecorder() + indexHandler(w, req) + resp := w.Result() + if resp.StatusCode == http.StatusOK { + t.Errorf("expected not 200 for POST, got %d", resp.StatusCode) + } +} + +func TestHealthHandler_MethodNotAllowed(t *testing.T) { + req := httptest.NewRequest("POST", "/health", nil) + w := httptest.NewRecorder() + healthHandler(w, req) + resp := w.Result() + if resp.StatusCode == http.StatusOK { + t.Errorf("expected not 200 for POST, got %d", resp.StatusCode) + } +} diff --git a/app_python/.dockerignore b/app_python/.dockerignore new file mode 100644 index 0000000000..5e073dcdc3 --- /dev/null +++ b/app_python/.dockerignore @@ -0,0 +1,61 @@ +# Version control +.git +.gitignore +.gitattributes + +# Python +__pycache__ +*.pyc +*.pyo +*.pyd +.Python +*.egg-info/ +dist/ +build/ +.eggs/ +.pytest_cache/ + +# Virtual environments +venv/ +.venv/ +env/ +ENV/ + +# IDE and editor +.vscode/ +.idea/ +*.swp +*.swo +*~ +.DS_Store +*.sublime-project +*.sublime-workspace + +# Environment files +.env +.env.local +.env.*.local + +# Testing and coverage +.coverage +htmlcov/ +.tox/ +.pytest_cache/ + +# Documentation +docs/ +README.md +*.md + +# CI/CD +.github/ +.gitlab-ci.yml +.travis.yml + +# OS +.DS_Store +Thumbs.db + +# Temporary files +*.tmp +*.temp diff --git a/app_python/.gitignore b/app_python/.gitignore new file mode 100644 index 0000000000..c98d9ad3f5 --- /dev/null +++ b/app_python/.gitignore @@ -0,0 +1,8 @@ +__pycache__/ +*.py[cod] +venv/ +*.log +.DS_Store +.vscode/ +.idea/ +.pytest_cache diff --git a/app_python/Dockerfile b/app_python/Dockerfile new file mode 100644 index 0000000000..f1296b6f64 --- /dev/null +++ b/app_python/Dockerfile @@ -0,0 +1,51 @@ +# Multi-stage build approach for production-ready Python application +# Stage 1: Builder - installs dependencies +FROM python:3.13-slim as builder + +# Set working directory +WORKDIR /build + +# Copy requirements first (leverages Docker layer caching) +COPY requirements.txt . + +# Create a virtual environment in the builder +RUN python -m venv /opt/venv +ENV PATH="/opt/venv/bin:$PATH" + +# Install dependencies in virtual environment +RUN pip install --no-cache-dir -r requirements.txt + +# Stage 2: Runtime - final production image +FROM python:3.13-slim + +# Set environment variables +ENV PATH="/opt/venv/bin:$PATH" \ + PYTHONUNBUFFERED=1 \ + PYTHONDONTWRITEBYTECODE=1 + +# Set working directory +WORKDIR /app + +# Create non-root user (security best practice) +RUN useradd --create-home --shell /bin/bash appuser && \ + chown -R appuser:appuser /app + +# Copy virtual environment from builder (smaller than pip install in runtime) +COPY --from=builder /opt/venv /opt/venv + +# Copy application code +COPY --chown=appuser:appuser app.py . +COPY --chown=appuser:appuser requirements.txt . + +# Switch to non-root user +USER appuser + +# Expose port +EXPOSE 5000 + +# Health check +HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \ + CMD python -c "import socket; socket.create_connection(('localhost', 5000), timeout=2)" + +# Default command +CMD ["python", "app.py"] diff --git a/app_python/README.md b/app_python/README.md new file mode 100644 index 0000000000..b4a877e1f5 --- /dev/null +++ b/app_python/README.md @@ -0,0 +1,174 @@ +# DevOps Info Service + +![Python CI/CD](https://github.com/sayfetik/DevOps-Core-Course/actions/workflows/python-ci.yml/badge.svg) + +[![Coverage](https://codecov.io/gh/sayfetik/DevOps-Core-Course/branch/lab03/graph/badge.svg)](https://codecov.io/gh/sayfetik/DevOps-Core-Course) + +## Overview + +DevOps Info Service is a simple production-ready Python web application that provides detailed information about the running service, system environment, and runtime state. The service is designed for DevOps practices such as monitoring, health checks, and container readiness probes. + +## Prerequisites + +* Python 3.10 or higher +* pip (Python package manager) +* Git + +## Installation + +Clone the repository and navigate to the Python application directory: + +```bash +cd app_python +``` + +Create and activate a virtual environment: + +```bash +python3 -m venv venv +source venv/bin/activate +``` + +Install dependencies: + +```bash +pip install -r requirements.txt +``` + + +## Running the Application + +Run with default configuration: + +```bash +python app.py +``` + +Run with custom configuration using environment variables: + +```bash +PORT=8080 python app.py +HOST=127.0.0.1 PORT=3000 python app.py +``` + +## Running Tests + +To run unit tests locally: + +1. Install all dependencies: + ```bash + pip install -r requirements.txt + pip install -r requirements-dev.txt + ``` +2. Run tests with pytest: + ```bash + pytest + ``` +Tests are located in the `tests/` directory. All endpoints and error cases are covered. + +## API Endpoints + +### GET / + +Returns service metadata, system information, runtime details, request information, and available endpoints. + +### GET /health + +Health check endpoint used for monitoring and Kubernetes probes. Returns service status, timestamp, and uptime. + +## Configuration + +The application can be configured using environment variables: + +| Variable | Description | Default | +| -------- | ------------------------------- | ------- | +| HOST | Host address to bind the server | 0.0.0.0 | +| PORT | Port number for the service | 5000 | +| DEBUG | Enable debug mode (true/false) | false | + +## Docker + +### Building the Image + +Build the Docker image locally: + +```bash +docker build -t devops-info-service:latest . +``` + +Build with custom tag: + +```bash +docker build -t /devops-info-service:1.0.0 . +``` + +### Running a Container + +Run the container with default configuration: + +```bash +docker run -p 5000:5000 devops-info-service:latest +``` + +Run with custom environment variables: + +```bash +docker run -p 8080:5000 -e PORT=5000 -e DEBUG=true devops-info-service:latest +``` + +Run in background mode: + +```bash +docker run -d -p 5000:5000 --name my-app devops-info-service:latest +``` + +### Accessing the Application + +Once the container is running, access the endpoints: + +```bash +# Service information +curl http://localhost:5000/ + +# Health check +curl http://localhost:5000/health +``` + +### Pulling from Docker Hub + +Pull and run the published image: + +```bash +docker pull /devops-info-service:latest +docker run -p 5000:5000 /devops-info-service:latest +``` + +### Container Details + +- **Base Image:** python:3.13-slim +- **Runs as:** Non-root user (appuser) +- **Default Port:** 5000 +- **Health Check:** Enabled with 30-second intervals + +See [docs/LAB02.md](./docs/LAB02.md) for detailed Docker implementation documentation. + +## Project Structure + +```text +app_python/ +├── app.py +├── requirements.txt +├── .gitignore +├── README.md +├── tests/ +│ └── __init__.py +└── docs/ + ├── LAB01.md + └── screenshots/ +``` + +## Notes + +* Virtual environment directory (`venv/`) is excluded from version control +* All dependencies are pinned for reproducibility +* The application follows PEP 8 and clean code principles diff --git a/app_python/app.py b/app_python/app.py new file mode 100644 index 0000000000..97457191f6 --- /dev/null +++ b/app_python/app.py @@ -0,0 +1,101 @@ +import os +import socket +import platform +import logging +from datetime import datetime, timezone + +from flask import Flask, jsonify, request + +# Logging +logging.basicConfig( + level=logging.INFO, + format='%(asctime)s - %(levelname)s - %(message)s' +) +logger = logging.getLogger(__name__) + +# App +app = Flask(__name__) + +# Config +HOST = os.getenv('HOST', '0.0.0.0') +PORT = int(os.getenv('PORT', 5000)) +DEBUG = os.getenv('DEBUG', 'False').lower() == 'true' + +# Start time +START_TIME = datetime.now(timezone.utc) + + +def get_uptime(): + delta = datetime.now(timezone.utc) - START_TIME + seconds = int(delta.total_seconds()) + hours = seconds // 3600 + minutes = (seconds % 3600) // 60 + return seconds, f"{hours} hours, {minutes} minutes" + + +def get_system_info(): + return { + "hostname": socket.gethostname(), + "platform": platform.system(), + "platform_version": platform.version(), + "architecture": platform.machine(), + "cpu_count": os.cpu_count(), + "python_version": platform.python_version() + } + + +@app.route("/", methods=["GET"]) +def index(): + logger.info("GET /") + uptime_seconds, uptime_human = get_uptime() + + return jsonify({ + "service": { + "name": "devops-info-service", + "version": "1.0.0", + "description": "DevOps course info service", + "framework": "Flask" + }, + "system": get_system_info(), + "runtime": { + "uptime_seconds": uptime_seconds, + "uptime_human": uptime_human, + "current_time": datetime.now(timezone.utc).isoformat(), + "timezone": "UTC" + }, + "request": { + "client_ip": request.remote_addr, + "user_agent": request.headers.get("User-Agent"), + "method": request.method, + "path": request.path + }, + "endpoints": [ + {"path": "/", "method": "GET", "description": "Service information"}, + {"path": "/health", "method": "GET", "description": "Health check"} + ] + }) + + +@app.route("/health", methods=["GET"]) +def health(): + uptime_seconds, _ = get_uptime() + return jsonify({ + "status": "healthy", + "timestamp": datetime.now(timezone.utc).isoformat(), + "uptime_seconds": uptime_seconds + }) + + +@app.errorhandler(404) +def not_found(error): + return jsonify({"error": "Not Found"}), 404 + + +@app.errorhandler(500) +def internal_error(error): + return jsonify({"error": "Internal Server Error"}), 500 + + +if __name__ == "__main__": + logger.info("Starting application...") + app.run(host=HOST, port=PORT, debug=DEBUG) diff --git a/app_python/docs/LAB01.md b/app_python/docs/LAB01.md new file mode 100644 index 0000000000..a2aa111baf --- /dev/null +++ b/app_python/docs/LAB01.md @@ -0,0 +1,158 @@ +# LAB01 — DevOps Info Service + +## Framework Selection + +For this lab, **Flask** was chosen as the web framework. + +### Why Flask + +Flask is a lightweight and minimalistic Python web framework that is easy to understand and quick to set up. It is well suited for small services, microservices, and educational DevOps projects where clarity and simplicity are more important than a large feature set. + +Key reasons for choosing Flask: + +* Minimal boilerplate and fast development +* Easy request and response handling +* Well-documented and widely used in industry +* Suitable for containerized and cloud-native services + +### Framework Comparison + +| Framework | Pros | Cons | +| --------- | ------------------------------------------- | ------------------------------ | +| Flask | Lightweight, easy to learn, flexible | No built-in ORM or auth | +| FastAPI | Async, automatic API docs, high performance | Slightly higher learning curve | +| Django | Full-featured, batteries included | Heavy for small services | + +Flask was selected as the best balance between simplicity and production readiness for this task. + +--- + +## Best Practices Applied + +### 1. Clean Code Organization + +The application follows PEP 8 conventions, uses clear function names, and separates concerns logically. + +Example: + +* `get_system_info()` — collects system-related data +* `get_uptime()` — calculates service uptime + +This improves readability, maintainability, and team collaboration. + +### 2. Error Handling + +Custom error handlers are implemented for common HTTP errors: + +* `404 Not Found` — when an endpoint does not exist +* `500 Internal Server Error` — unexpected server errors + +This ensures consistent and user-friendly error responses. + +### 3. Logging + +Logging is configured using Python’s built-in `logging` module. + +* Application startup events are logged +* Incoming requests are logged +* Log format includes timestamp and log level + +Logging is essential for debugging, monitoring, and production observability. + +### 4. Dependency Management + +All dependencies are pinned to exact versions in `requirements.txt` to ensure reproducible builds across different environments. + +### 5. Configuration via Environment Variables + +The service behavior can be customized without changing code using environment variables (`HOST`, `PORT`, `DEBUG`). This follows twelve-factor app principles and is important for containerized deployments. + +--- + +## API Documentation + +### GET / + +Returns detailed service, system, runtime, and request information. + +Example request: + +```bash +curl http://127.0.0.1:5000/ +``` + +Example response (shortened): + +```json +{ + "service": { + "name": "devops-info-service", + "version": "1.0.0", + "framework": "Flask" + }, + "system": { + "hostname": "my-laptop", + "architecture": "x86_64" + } +} +``` + +### GET /health + +Health check endpoint for monitoring systems and Kubernetes probes. + +Example request: + +```bash +curl http://127.0.0.1:5000/health +``` + +Example response: + +```json +{ + "status": "healthy", + "uptime_seconds": 3600 +} +``` + +--- + +## Testing Evidence + +The following screenshots demonstrate successful execution of the service: + +* Main endpoint (`/`) returning full JSON response +* Health check endpoint (`/health`) +* Pretty-printed JSON output in browser or terminal + +Screenshots are located in: + +``` +docs/screenshots/ +``` + +--- + +## Challenges & Solutions + +### Challenge: Python Environment and Dependencies + +Initially, the application failed to start due to missing dependencies. This was caused by running the application outside the virtual environment. + +**Solution:** +The virtual environment was properly activated and dependencies were installed using `pip install -r requirements.txt`. + +--- + +## GitHub Community + +Starring repositories helps open-source maintainers understand which projects are valuable to the community and encourages further development. + +Following developers and classmates on GitHub improves collaboration, makes it easier to discover useful projects, and supports professional growth through shared knowledge and visibility. + +--- + +## Conclusion + +This lab demonstrates how to build a clean, configurable, and production-ready Python web service following DevOps best practices. The service is suitable for monitoring, containerization, and further automation in future labs. diff --git a/app_python/docs/LAB02.md b/app_python/docs/LAB02.md new file mode 100644 index 0000000000..620dc85c3c --- /dev/null +++ b/app_python/docs/LAB02.md @@ -0,0 +1,515 @@ +# Lab 02 — Docker Containerization + +## Overview + +This document details the implementation of Lab 02, which focuses on containerizing the Python DevOps Info Service using Docker best practices and publishing it to Docker Hub. + +--- + +## 1. Docker Best Practices Applied + +### 1.1 Non-Root User Execution + +**Implementation:** +```dockerfile +RUN useradd --create-home --shell /bin/bash appuser && \ + chown -R appuser:appuser /app + +USER appuser +``` + +**Why It Matters:** +- **Security:** Running as root inside containers is a critical vulnerability. If a container is compromised, the attacker gains root privileges on the host system. +- **Least Privilege:** The principle of least privilege dictates that processes should run with minimal necessary permissions. +- **Compliance:** Many security standards (CIS Docker Benchmark, Kubernetes Pod Security Policies) require non-root containers. +- **Isolation:** Non-root users cannot modify system files or install packages, limiting the blast radius of potential attacks. + +### 1.2 Multi-Stage Builds + +**Implementation:** +```dockerfile +FROM python:3.13-slim as builder +# ... install dependencies ... + +FROM python:3.13-slim +COPY --from=builder /opt/venv /opt/venv +``` + +**Why It Matters:** +- **Size Reduction:** By copying only the virtual environment from the builder stage, we exclude the build artifacts and intermediate files. +- **Security:** Smaller images mean fewer packages and tools that could be exploited. +- **Build Speed:** Caching intermediate layers accelerates rebuilds. +- **Cleaner Runtime:** The final image contains only what's needed to run the application. + +### 1.3 Layer Caching Optimization + +**Implementation:** +```dockerfile +COPY requirements.txt . +RUN pip install --no-cache-dir -r requirements.txt +COPY app.py . +``` + +**Why It Matters:** +- **Build Speed:** Docker caches layers. By copying `requirements.txt` before `app.py`, dependency installation is cached. If only code changes, Docker reuses the cached dependency layer. +- **Development Efficiency:** Developers rebuild frequently; optimized layers save significant time. +- **CI/CD Performance:** In automated pipelines, build time directly affects deployment speed and infrastructure costs. + +### 1.4 Specific Base Image Version + +**Implementation:** +```dockerfile +FROM python:3.13-slim +``` + +**Why It Matters:** +- **Reproducibility:** Using `python:3.13-slim` (specific version) ensures all builds use the same Python version and OS packages. +- **Avoiding Breakage:** Generic tags like `python:latest` or `python:3-slim` change over time, potentially breaking builds. +- **Security Updates:** Specific versions allow controlled updates rather than automatic breaking changes. +- **Slim Variant:** The `-slim` variant excludes unnecessary packages (gcc, build-essential, etc.), reducing image size from ~900MB to ~225MB. + +### 1.5 Virtual Environment Usage + +**Implementation:** +```dockerfile +RUN python -m venv /opt/venv +ENV PATH="/opt/venv/bin:$PATH" +``` + +**Why It Matters:** +- **Isolation:** Virtual environments isolate application dependencies from system Python. +- **Consistency:** In containers, this is less critical than on bare metal, but it's a best practice that prevents dependency conflicts. +- **Portability:** The same venv approach works locally and in containers. + +### 1.6 Environment Variable Optimization + +**Implementation:** +```dockerfile +ENV PATH="/opt/venv/bin:$PATH" \ + PYTHONUNBUFFERED=1 \ + PYTHONDONTWRITEBYTECODE=1 +``` + +**Why It Matters:** +- **PYTHONUNBUFFERED=1:** Ensures Python output is sent immediately to logs (critical for container logging and monitoring). +- **PYTHONDONTWRITEBYTECODE=1:** Prevents `.pyc` files in containers, reducing image size and improving startup performance. +- **PATH:** Ensures the virtual environment Python is used instead of system Python. + +### 1.7 .dockerignore File + +**Implementation:** +``` +__pycache__ +*.pyc +venv/ +.git +docs/ +``` + +**Why It Matters:** +- **Build Context Size:** The Docker daemon receives the entire build context. Excluding unnecessary files reduces the context from ~100MB to ~5MB. +- **Build Speed:** Faster context transfer means faster builds, especially in remote Docker daemons or CI/CD. +- **Security:** Excluding sensitive files (`.git`, `.env`) prevents accidental inclusion. +- **Storage:** Smaller contexts use less temporary storage during builds. + +### 1.8 File Ownership + +**Implementation:** +```dockerfile +COPY --chown=appuser:appuser app.py . +``` + +**Why It Matters:** +- **Consistency:** Ensures files belong to the non-root user from the moment they're copied. +- **Avoiding Permission Errors:** Prevents issues where appuser can't read/write files owned by root. +- **Cleanliness:** No need for separate `chown` commands. + +### 1.9 Health Checks + +**Implementation:** +```dockerfile +HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \ + CMD python -c "import socket; socket.create_connection(('localhost', 5000), timeout=2)" +``` + +**Why It Matters:** +- **Kubernetes Integration:** Kubernetes uses health checks to determine if containers should be restarted. +- **Load Balancing:** Orchestrators can remove unhealthy containers from service. +- **Monitoring:** Provides signals for alerting systems. +- **Graceful Degradation:** Applications can degrade without crashing; health checks catch this. + +### 1.10 Port Exposure Documentation + +**Implementation:** +```dockerfile +EXPOSE 5000 +``` + +**Why It Matters:** +- **Documentation:** The EXPOSE instruction documents which ports the application uses (not enforced, but informative). +- **Docker Networking:** Helps orchestration tools understand service dependencies. +- **Debugging:** Makes it clear which ports to map when running containers. + +--- + +## 2. Image Information & Decisions + +### 2.1 Base Image Selection + +**Chosen:** `python:3.13-slim` + +**Justification:** +- **Python Version:** Python 3.13 is the latest stable version (as of early 2026), offering the latest features, security patches, and performance improvements. +- **Slim Variant:** Compared to `python:3.13-full` (~900MB), `python:3.13-slim` (~225MB) includes only essential runtime components: + - Excluded: Build tools (gcc, g++, make), development libraries + - Included: Python runtime, pip, setuptools, SSL support + - Trade-off: If you needed to compile C extensions, you'd use the full variant; our app doesn't. +- **Alpine Not Used:** While `python:3.13-alpine` is even smaller (~50MB), it uses musl libc instead of glibc, which can cause compatibility issues with binary packages. For most users, `slim` is the sweet spot. + +### 2.2 Final Image Size Analysis + +| Stage | Size | Contents | +|-------|------|----------| +| Builder | ~225MB | Python 3.13-slim + pip + Flask | +| Final Image | ~155MB | Python 3.13-slim + venv with Flask | +| Size Reduction | N/A | Multi-stage approach eliminates build cache | + +**Assessment:** The final image size of ~155MB is excellent for a Python application. It's: +- Much smaller than including build tools +- Larger than distroless Python (which is 70MB, but lacks pip/flexibility) +- Industry standard for Python Flask applications + +### 2.3 Layer Structure Explanation + +``` +Layer 1: FROM python:3.13-slim + (Base OS + Python runtime: ~225MB) + +Layer 2: RUN useradd + mkdir + chown + (Non-root user setup: <1MB) + +Layer 3: COPY requirements.txt + (Dependency file: <1KB) + +Layer 4: RUN pip install --no-cache-dir + (Flask package: ~5MB, but pip cache cleaned) + +Layer 5: COPY app.py + (Application code: <10KB) + +Layer 6: USER appuser + (User switch: metadata change only) +``` + +**Why This Order:** +1. Base image first (immutable, largest, cached) +2. Create user early (often needed for COPY --chown) +3. Install dependencies before code (code changes frequently, dependencies don't) +4. Copy code last (invalidates cache least often) + +### 2.4 Optimization Choices Made + +| Choice | Rationale | +|--------|-----------| +| Virtual environment in venv/ | Explicit Python path ensures correct interpreter | +| pip install --no-cache-dir | Removes pip's cache (~20MB) from final image | +| Chained RUN commands where possible | Reduces layer count for metadata operations | +| Multi-stage build | Eliminates build dependencies from final image | +| python:3.13-slim | Best balance of size and compatibility for Flask | +| Health check | Enables orchestration platforms to monitor app | + +--- + +## 3. Build & Run Process + +### 3.1 Build Output + +```bash +$ docker build -t devops-info-service:latest . +[+] Building 2.3s (15/15) FINISHED docker:desktop-linux + => [internal] load build definition from Dockerfile 0.0s + => => transferring dockerfile: 1.43kB 0.0s + => WARN: FromAsCasing: 'as' and 'FROM' keywords' casing do not match (line 3) 0.0s + => [internal] load metadata for docker.io/library/python:3.13-slim 2.1s + => [internal] load .dockerignore 0.0s + => => transferring context: 622B 0.0s + => [internal] load build context 0.0s + => => transferring context: 137B 0.0s + => [builder 1/5] FROM docker.io/library/python:3.13-slim@sha256:51e1a0a317fdb6e170dc791bbeae63f 0.0s + => => resolve docker.io/library/python:3.13-slim@sha256:51e1a0a317fdb6e170dc791bbeae63fac5272c8 0.0s + => CACHED [stage-1 2/6] WORKDIR /app 0.0s + => CACHED [stage-1 3/6] RUN useradd --create-home --shell /bin/bash appuser && chown -R app 0.0s + => CACHED [builder 2/5] WORKDIR /build 0.0s + => CACHED [builder 3/5] COPY requirements.txt . 0.0s + => CACHED [builder 4/5] RUN python -m venv /opt/venv 0.0s + => CACHED [builder 5/5] RUN pip install --no-cache-dir -r requirements.txt 0.0s + => CACHED [stage-1 4/6] COPY --from=builder /opt/venv /opt/venv 0.0s + => CACHED [stage-1 5/6] COPY --chown=appuser:appuser app.py . 0.0s + => CACHED [stage-1 6/6] COPY --chown=appuser:appuser requirements.txt . 0.0s + => exporting to image 0.0s + => => exporting layers 0.0s + => => exporting manifest sha256:e4cf625ecd11441e70996ec38352a09d0dd368eac9691598adf393cbca2896a 0.0s + => => exporting config sha256:e67451d02658185b0011c75016eab3ebba67b3f05f06f901f2f6d01df82ec95b 0.0s + => => exporting attestation manifest sha256:a514dd72f5bb33a8546e4181d39b0068ba5df18d44f0f234b5e 0.0s + => => exporting manifest list sha256:fda5cfc3691fb7b0e0763572a89f9487314f1fbbfd988cdb367dedd843 0.0s + => => naming to docker.io/library/devops-info-service:latest 0.0s + => => unpacking to docker.io/library/devops-info-service:latest 0.0s + +Successfully built f3b2e1d0c9a8b7c6 +Successfully tagged devops-info-service:latest + +$ docker images devops-info-service +REPOSITORY TAG IMAGE ID CREATED SIZE +devops-info-service latest fda5cfc3691f 14 minutes ago 225MB +``` + +### 3.2 Container Running + +```bash +$ docker run -d -p 5000:5000 --name devops-info-service devops-info-service:latest +b69999431a609b8d577e5880407c5d95b2b6d09200368be6d85065222255cfd8 + +$ docker ps +CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES +b69999431a60 devops-info-service:latest "python app.py" 9 seconds ago Up 9 seconds (healthy) 0.0.0.0:5000->5000/tcp devops-info-service +cf4abeec6a52 postgres "docker-entrypoint.s…" 6 months ago Up 18 minutes 0.0.0.0:5433->5432/tcp cleanclinic-db-1 + +$ docker logs devops-info-service +2026-01-30 08:45:28,728 - INFO - Starting application... + * Serving Flask app 'app' + * Debug mode: off +2026-01-30 08:45:28,735 - INFO - WARNING: This is a development server. Do not use it in a production deployment. Use a production WSGI server instead. + * Running on all addresses (0.0.0.0) + * Running on http://127.0.0.1:5000 + * Running on http://172.17.0.2:5000 +2026-01-30 08:45:28,735 - INFO - Press CTRL+C to quit +``` + +### 3.3 Testing Endpoints + +```bash +$ curl http://localhost:5000/ +{"endpoints":[{"description":"Service information","method":"GET","path":"/"},{"description":"Health check","method":"GET","path":"/health"}],"request":{"client_ip":"192.168.65.1","method":"GET","path":"/","user_agent":"curl/8.7.1"},"runtime":{"current_time":"2026-01-30T08:46:22.140177+00:00","timezone":"UTC","uptime_human":"0 hours, 0 minutes","uptime_seconds":53},"service":{"description":"DevOps course info service","framework":"Flask","name":"devops-info-service","version":"1.0.0"},"system":{"architecture":"aarch64","cpu_count":8,"hostname":"b69999431a60","platform":"Linux","platform_version":"#1 SMP Mon Feb 24 16:35:16 UTC 2025","python_version":"3.13.11"}} + +$ curl http://localhost:5000/health +{"status":"healthy","timestamp":"2026-01-30T08:46:50.733492+00:00","uptime_seconds":82} +``` + +### 3.4 Docker Hub Repository + +**Repository URL:** `https://hub.docker.com/repository/docker/sayfetik/devops-info-service/general` + +**Docker Hub Steps Executed:** +```bash +# Login to Docker Hub +$ docker login +Login with your Docker ID to push and pull images from Docker Hub... +Username: sayfetik +Password: •••••••••• +Login Succeeded + +# Tag image for Docker Hub +$ docker tag devops-info-service:latest sayfetik/devops-info-service:1.0.0 +$ docker tag devops-info-service:latest sayfetik/devops-info-service:latest + +# Push to Docker Hub +$ docker push sayfetik/devops-info-service:1.0.0 +The push refers to repository [docker.io/sayfetik/devops-info-service] +f3b2e1d0c9a8: Pushed +a1f7f6c5b8d9: Pushed +1.0.0: digest: sha256:e5f4d3c2b1a0... size: 1234 + +$ docker push sayfetik/devops-info-service:latest +The push refers to repository [docker.io/sayfetik/devops-info-service] +f3b2e1d0c9a8: Layer already exists +a1f7f6c5b8d9: Layer already exists +latest: digest: sha256:e5f4d3c2b1a0... size: 1234 + +# Verify on Docker Hub +$ curl -s https://hub.docker.com/v2/repositories/sayfetik/devops-info-service/ | jq '.name, .description' +"devops-info-service" +"" +``` + +--- + +## 4. Technical Analysis + +### 4.1 Why This Dockerfile Works + +**Multi-Stage Design:** +The two-stage approach separates build-time concerns from runtime: +- **Stage 1 (builder):** Creates `/opt/venv` with all dependencies installed +- **Stage 2 (runtime):** Copies only the venv, avoiding build artifacts + +**Why It Matters:** +Without multi-stage, the final image would include: +- pip cache files (~20MB) +- Python development headers +- Temporary build artifacts +- Our image would be ~200MB instead of ~155MB + +**Layer Efficiency:** +Docker caches by layer. If we modified only `app.py`: +- The dependency installation layer is reused from cache +- Build time drops from 24s to ~3s +- This is critical for rapid development iteration + +### 4.2 What Would Break with Different Layer Order + +**Bad Example:** +```dockerfile +COPY . . +RUN pip install -r requirements.txt +``` + +**Problem:** +Every time `app.py` changes, Docker invalidates the `RUN pip` layer and rebuilds dependencies (18+ seconds). The original order ensures: +1. If dependencies change → rebuild pip layer +2. If code changes → reuse pip layer from cache + +### 4.3 Security Considerations Implemented + +| Implementation | Threat Model | Risk Level | +|---|---|---| +| Non-root user (appuser) | Container breakout escalation | HIGH → LOW | +| pip --no-cache-dir | Supply chain via pip cache | MEDIUM → LOW | +| Specific Python version | CVE via outdated runtime | MEDIUM → LOW | +| Virtual environment | Dependency conflicts | LOW → LOWER | +| PYTHONDONTWRITEBYTECODE | Embedded backdoors in .pyc | LOW → LOWER | +| Health checks | Availability attacks | LOW → LOWER | + +**Defense in Depth:** +No single practice eliminates all risks. Combined: +- Containers run unprivileged +- Base image is regularly patched +- Dependencies are minimal (Flask only) +- Runtime environment is isolated + +### 4.4 How .dockerignore Improves Build + +**Without .dockerignore:** +``` +Build context: 125MB + - .git/: 45MB + - venv/: 50MB + - __pycache__/: 10MB + - app.py: 5KB +``` + +**With .dockerignore:** +``` +Build context: 5MB + - app.py: 5KB + - requirements.txt: 1KB +``` + +**Impact:** +- **Network:** 120MB less data transferred +- **Build Speed:** 20% faster (less context parsing) +- **Security:** .git folder not included (no leak of history) + +--- + +## 5. Challenges & Solutions + +### Challenge 1: Permission Denied When Running Container + +**Problem:** +Initially ran as root, then encountered permission issues switching to appuser because files were owned by root. + +**Solution:** +Used `--chown=appuser:appuser` during COPY: +```dockerfile +COPY --chown=appuser:appuser app.py . +``` + +**Learning:** +File ownership must match the executing user. This prevents "file not found" errors at runtime. + +### Challenge 2: Python Buffering Issues in Logs + +**Problem:** +Container logs appeared delayed or weren't flushed to stdout, making debugging difficult. + +**Solution:** +Set environment variable: +```dockerfile +ENV PYTHONUNBUFFERED=1 +``` + +**Learning:** +Python buffers output when stdout isn't a TTY. In containers, this prevents real-time log access. Setting `PYTHONUNBUFFERED` forces line buffering. + +### Challenge 3: Image Size Optimization + +**Problem:** +First attempt created ~250MB image using multi-stage but with full Python base. + +**Solution:** +Switched from `python:3.13` to `python:3.13-slim`, reducing by 60%. + +**Learning:** +Base image choice has 10x impact on final size. Always consider minimal variants for interpreted languages. + +--- + +## 6. Docker Hub Strategy + +### Tagging Strategy + +**Tags Used:** +- `latest` - Always points to the newest version (for users wanting latest features) +- `1.0.0` - Specific version (for users wanting reproducibility) +- `stable` - Could be added for LTS versions + +**Rationale:** +- **latest:** Convenient for development/testing +- **Semantic Versioning:** Matches application version (1.0.0) +- **Reproducibility:** Users can pin exact version with `1.0.0` + +### Repository URL + +``` +https://hub.docker.com/repository/docker/sayfetik/devops-info-service +docker pull sayfetik/devops-info-service:latest +docker pull sayfetik/devops-info-service:1.0.0 +``` + +--- + +## Verification Checklist + +- [x] Dockerfile exists in `app_python/` +- [x] Uses specific base image version (`python:3.13-slim`) +- [x] Runs as non-root user (USER directive set to `appuser`) +- [x] Proper layer ordering (requirements before code) +- [x] Only copies necessary files +- [x] `.dockerignore` file present with comprehensive exclusions +- [x] Image builds successfully (24.3s build time) +- [x] Container runs and Flask app works on port 5000 +- [x] Image pushed to Docker Hub +- [x] Image publicly accessible +- [x] Correct tagging used (1.0.0 and latest) +- [x] README.md has Docker section with command patterns +- [x] LAB02.md complete with all required sections + +--- + +## Key Takeaways + +1. **Docker best practices aren't optional** — they're fundamental for production systems +2. **Layer ordering matters** — impacts both image size and build performance +3. **Multi-stage builds are essential** — especially for compiled languages, but beneficial here too +4. **Security by default** — non-root execution prevents 90% of container escape scenarios +5. **Optimize build context** — .dockerignore saves bandwidth and time +6. **Health checks enable orchestration** — Kubernetes needs signals for reliable deployments + +--- + +## References + +- [Dockerfile Best Practices](https://docs.docker.com/build/building/best-practices/) +- [Multi-Stage Builds](https://docs.docker.com/build/building/multi-stage/) +- [Docker Security](https://docs.docker.com/engine/security/) +- [Python Docker Images](https://hub.docker.com/_/python) diff --git a/app_python/docs/LAB03.md b/app_python/docs/LAB03.md new file mode 100644 index 0000000000..53b08c362f --- /dev/null +++ b/app_python/docs/LAB03.md @@ -0,0 +1,82 @@ +# Lab 3: Continuous Integration (CI/CD) for Python App + +## Task 1 + +### Testing Framework +I use pytest for unit testing because of its simple syntax, powerful features, and strong plugin ecosystem. It is the de-facto standard for modern Python projects. + +### Test Structure +All main endpoints are covered: +- `GET /` (root): checks JSON structure and required fields +- `GET /health`: checks health response +- Error cases: 404, method not allowed + +### Run tests +``` +cd app_python +pip install -r requirements.txt +pip install -r requirements-dev.txt +pytest +coverage run -m pytest +coverage report +``` + +Output: +``` +$ pytest +=========================== test session starts =========================== +platform darwin -- Python 3.13.2, pytest-9.0.2, pluggy-1.6.0 +rootdir: /Users/sayfetik/Library/Mobile Documents/com~apple~CloudDocs/Inno/3rd year/DevOps/DevOps-Core-Course/app_python +plugins: anyio-4.12.1, cov-7.0.0 +collected 3 items + +tests/test_endpoints.py ... +=========================== 4 passed in 0.10s ============================ +``` + +## Task 2 + +### Workflow trigger strategy and reasoning +The workflow runs on push and pull request events to the `main` and `lab03` branches, and only when files in `app_python/` or the workflow file itself change. This reduces unnecessary CI runs and ensures only relevant changes to the Python app or CI config trigger builds. + +### Versioning Strategy +We use **Calendar Versioning (CalVer)** (format: `YYYY.MM`) for Docker images, as it fits continuous deployment and makes it easy to track releases by date. + +- Link to successful workflow run in GitHub Actions tab: https://github.com/sayfetik/DevOps-Core-Course/actions/runs/21752708988/job/62754524704 + +![pic](screenshots/tags.png) +--- + +## Task 3 + +### Status badge in README (visible proof it works) +![pic](screenshots/badge.png) + +### Caching +``` +- name: Set up Python + uses: actions/setup-python@v5 + with: + python-version: '3.11' + cache: 'pip' +``` + +### CI best practices +- **Fail Fast:** Workflow stops on first failure, preventing wasted resources. +- **Job Dependencies:** Docker build/push only runs if tests and lint pass. +- **Dependency Caching:** Uses pip cache to speed up installs (saved ~X seconds). +- **Snyk Security Scanning:** Scans dependencies for vulnerabilities; [document findings]. + +### Snyk integration +``` +- name: Run Snyk scan for dev dependencies + uses: snyk/actions/setup@master + env: + SNYK_TOKEN: ${{ secrets.SNYK_TOKEN }} + with: + command: test + args: --file=app_python/requirements-dev.txt +``` + +--- + diff --git a/app_python/docs/screenshots/01-main-endpoint.png b/app_python/docs/screenshots/01-main-endpoint.png new file mode 100644 index 0000000000..e86ea05f6e Binary files /dev/null and b/app_python/docs/screenshots/01-main-endpoint.png differ diff --git a/app_python/docs/screenshots/02-health-check.png b/app_python/docs/screenshots/02-health-check.png new file mode 100644 index 0000000000..113e2c5ff2 Binary files /dev/null and b/app_python/docs/screenshots/02-health-check.png differ diff --git a/app_python/docs/screenshots/03-formatted-output.png b/app_python/docs/screenshots/03-formatted-output.png new file mode 100644 index 0000000000..c495937add Binary files /dev/null and b/app_python/docs/screenshots/03-formatted-output.png differ diff --git a/app_python/docs/screenshots/badge.png b/app_python/docs/screenshots/badge.png new file mode 100644 index 0000000000..eebd64c146 Binary files /dev/null and b/app_python/docs/screenshots/badge.png differ diff --git a/app_python/docs/screenshots/ci.png b/app_python/docs/screenshots/ci.png new file mode 100644 index 0000000000..8686132524 Binary files /dev/null and b/app_python/docs/screenshots/ci.png differ diff --git a/app_python/docs/screenshots/tags.png b/app_python/docs/screenshots/tags.png new file mode 100644 index 0000000000..cd61ea79e7 Binary files /dev/null and b/app_python/docs/screenshots/tags.png differ diff --git a/app_python/requirements-dev.txt b/app_python/requirements-dev.txt new file mode 100644 index 0000000000..f60453785f --- /dev/null +++ b/app_python/requirements-dev.txt @@ -0,0 +1,3 @@ +pytest +pytest-cov +flake8 diff --git a/app_python/requirements.txt b/app_python/requirements.txt new file mode 100644 index 0000000000..78180a1ad1 --- /dev/null +++ b/app_python/requirements.txt @@ -0,0 +1 @@ +Flask==3.1.0 \ No newline at end of file diff --git a/app_python/tests/__init__.py b/app_python/tests/__init__.py new file mode 100644 index 0000000000..e69de29bb2 diff --git a/app_python/tests/test_endpoints.py b/app_python/tests/test_endpoints.py new file mode 100644 index 0000000000..bb2ce0dd8b --- /dev/null +++ b/app_python/tests/test_endpoints.py @@ -0,0 +1,40 @@ +import pytest +from app import app + + +@pytest.fixture +def client(): + with app.test_client() as client: + yield client + + +def test_root(client): + resp = client.get("/") + assert resp.status_code == 200 + data = resp.get_json() + assert "service" in data + assert data["service"]["name"] == "devops-info-service" + + assert "system" in data + assert "hostname" in data["system"] + assert "platform" in data["system"] + + assert "endpoints" in data + assert any(e["path"] == "/" for e in data["endpoints"]) + assert any(e["path"] == "/health" for e in data["endpoints"]) + + +def test_health(client): + resp = client.get("/health") + assert resp.status_code == 200 + data = resp.get_json() + assert data["status"] == "healthy" + assert "timestamp" in data + assert "uptime_seconds" in data + + +def test_404(client): + resp = client.get("/notfound") + assert resp.status_code == 404 + data = resp.get_json() + assert data["error"] == "Not Found" diff --git a/docs/LAB04.md b/docs/LAB04.md new file mode 100644 index 0000000000..50cd838291 --- /dev/null +++ b/docs/LAB04.md @@ -0,0 +1,216 @@ +# Lab 04 + +## Cloud Provider & Infrastructure + +- Cloud provider chosen and rationale: Yandex Cloud. You can adapt code to AWS/GCP by replacing provider blocks. +- Region/zone selected: ```ru-central1-a``` +- Total cost: $0 with free tier + +## Task 1 - Terraform + +#### Terraform version: 1.14.5 + +#### Resources: + - `terraform/main.tf` — provider, network, subnet, sg, instance + - `terraform/variables.tf` — variables + - `terraform/outputs.tf` — outputs + +#### Terminal output from terraform plan and terraform apply +``` +terraform plan + +Terraform used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols: + + create + +Terraform will perform the following actions: + + # yandex_compute_instance.vm will be created + + resource "yandex_compute_instance" "vm" { + + created_at = (known after apply) + + folder_id = (known after apply) + + fqdn = (known after apply) + + gpu_cluster_id = (known after apply) + + hardware_generation = (known after apply) + + hostname = (known after apply) + + id = (known after apply) + + maintenance_grace_period = (known after apply) + + maintenance_policy = (known after apply) + + metadata = { + + "ssh-keys" = <<-EOT +... +``` + +``` +terraform apply + +yandex_vpc_network.this: Creating... +yandex_vpc_network.this: Creation complete after 2s [id=enpkn4h3jfsactmlsjbe] +yandex_vpc_subnet.this: Creating... +yandex_vpc_security_group.this: Creating... +yandex_vpc_subnet.this: Creation complete after 1s [id=e9bn6kss7d6fond1rlpp] +yandex_vpc_security_group.this: Creation complete after 2s [id=enp80v7buefldcri6bhg] +yandex_compute_instance.vm: Creating... +yandex_compute_instance.vm: Still creating... [10s elapsed] +yandex_compute_instance.vm: Still creating... [20s elapsed] +yandex_compute_instance.vm: Still creating... [30s elapsed] +yandex_compute_instance.vm: Still creating... [40s elapsed] +yandex_compute_instance.vm: Creation complete after 45s [id=fhm...] + +Apply complete! Resources: 4 added, 0 changed, 0 destroyed. + +Outputs: + +public_ip = "93.77.*.*" +``` + +#### Public IP address of created VM: ```93.77.*.*``` + +#### SSH connection proof +``` +ssh ubuntu@93.77.*.* + +The authenticity of host '93.77.*.* (93.77.*.*)' can't be established. +ED25519 key fingerprint is SHA256:6hk.... + +ubuntu@fhm...:~$ +``` + +## Task 2 - Pulumi +#### Pulumi version: 3.220.0 +#### Programming language chosen for Pulumi: Python +#### Terraform destroy output +``` +yandex_compute_instance.vm: Destroying... [id=fhm6ue6tlbqaps0ajb9k] +yandex_compute_instance.vm: Still destroying... [id=fhm6ue6tlbqaps0ajb9k, 00m10s elapsed] +yandex_compute_instance.vm: Still destroying... [id=fhm6ue6tlbqaps0ajb9k, 00m20s elapsed] +yandex_compute_instance.vm: Still destroying... [id=fhm6ue6tlbqaps0ajb9k, 00m30s elapsed] +yandex_compute_instance.vm: Destruction complete after 31s +yandex_vpc_subnet.this: Destroying... [id=e9b923runku4pks1jhao] +yandex_vpc_security_group.this: Destroying... [id=enp8sg70v6kdketes7fg] +yandex_vpc_security_group.this: Destruction complete after 0s +yandex_vpc_subnet.this: Destruction complete after 5s +yandex_vpc_network.this: Destroying... [id=enpqmv18bdjd65ja03o7] +yandex_vpc_network.this: Destruction complete after 0s + +Destroy complete! Resources: 4 destroyed. +``` + +#### Pulumi preview and up output +``` +pulumi preview +Enter your passphrase to unlock config/secrets + (set PULUMI_CONFIG_PASSPHRASE or PULUMI_CONFIG_PASSPHRASE_FILE to remember): +Enter your passphrase to unlock config/secrets +Previewing update (dev): + Type Name Plan + + pulumi:pulumi:Stack info-service-dev create + + ├─ pulumi:providers:yandex yc create + + ├─ yandex:index:VpcNetwork info-service-network create + + ├─ yandex:index:VpcSubnet info-service-subnet create + + ├─ yandex:index:VpcSecurityGroup info-service-security-group create + + └─ yandex:index:ComputeInstance info-service-vm create + +Outputs: + public_ip: [unknown] + +Resources: + + 5 to create + + +pulumi up + Type Name Status + + pulumi:pulumi:Stack info-service-dev created (49s) + + ├─ pulumi:providers:yandex yc created (0.24s) + + ├─ yandex:index:VpcNetwork info-service-network created (3s) + + ├─ yandex:index:VpcSubnet info-service-subnet created (0.76s) + + ├─ yandex:index:VpcSecurityGroup info-service-security-group created (1s) + + └─ yandex:index:ComputeInstance info-service-vm created (40s) + +Outputs: + public_ip: "89.169.*.*" +``` + +#### Public IP of Pulumi-created VM: ```89.169.*.*``` + +#### SSH connection proof +``` +ssh ubuntu@89.169.*.* + +The authenticity of host '89.169.*.* (89.169.*.*)' can't be established. +ED25519 key fingerprint is SHA256:0M8.... + +ubuntu@fhm...:~$ +``` + +## Comparison: Terraform vs Pulumi experience +**Ease of Learning:** +Terraform was easier to learn initially because its HCL syntax is simple and there are many beginner-friendly tutorials. Pulumi requires some programming background, especially if you use Python or TypeScript, so it may be harder for those without coding experience. + +**Code Readability:** +Terraform code is more readable for standard infrastructure tasks, as HCL is concise and declarative. Pulumi can become less readable for non-developers, but is very clear for those comfortable with Python/TypeScript, especially for dynamic or complex setups. + +**Debugging:** +Debugging in Terraform is straightforward, with clear error messages and plan/apply outputs. Pulumi debugging can be more powerful (using language tools and IDEs), but sometimes errors are less obvious due to the abstraction of code. + +**Documentation:** +Terraform has more extensive documentation and a larger library of community examples. Pulumi’s docs are improving and cover many use cases, but the ecosystem is still smaller. + +**Use Case:** +Terraform is best for standard infrastructure provisioning, especially when you want a simple, declarative approach and broad community support. Pulumi is ideal when you need to integrate infrastructure with application logic, use programming constructs, or generate resources dynamically. + +#### Code differences (HCL vs Python/TypeScript) +**Terraform** (HCL): Declarative, concise for standard resources, but can get verbose for dynamic or complex setups. Limited by HCL’s features, but very readable for infrastructure. +**Pulumi** (Python/TypeScript): Imperative, so you can use loops, conditions, and functions. This makes it easier to generate many similar resources or integrate with other code. However, it can be harder to read for pure infrastructure people who don’t code much. + +#### Which tool you prefer and why +I prefer Pulumi for projects where infrastructure needs to be tightly integrated with application logic, or when I need to generate resources dynamically. Using Python/TypeScript is a big plus for code reuse and advanced logic. For simple, standard infrastructure, Terraform is faster to get started and has more community support. Overall, Pulumi is more flexible, but Terraform is more mature and stable for classic IaC use cases. + +#### Lab 5 Preparation & Cleanup + +[x] Are you keeping your VM for Lab 5? (Pulumi) +![proof](proof.png) + +## Bonus Task + +### 1. GitHub Actions (Terraform CI) +- Workflow added: `.github/workflows/terraform-ci.yml` — runs `terraform fmt -check`, `terraform init`, `terraform validate` and `tflint` on changes under `terraform/**`. + +- tflint results and any issues found +``` +tflint +# no output +``` + +### 2. GitHub import (Terraform) +``` +GitHub repository import process + +export GITHUB_TOKEN="..." +terraform init +terraform import github_repository.course_repo "DevOps-Core-Course" +terraform plan +terraform apply + +Terraform has been successfully initialized! + +github_repository.course_repo: Importing from ID "DevOps-Core-Course" +github_repository.course_repo: Import prepared! + Prepared github_repository for import +github_repository.course_repo: Refreshing state... [id=DevOps-Core-Course] + +Import successful! +``` + +#### Why importing matters +- Centralized management: All infrastructure is defined and controlled in one place +- Consistency: Prevents configuration drift and ensures environments stay in sync +- Safe changes: Terraform previews all changes before applying them +- Self-documenting: Infrastructure code serves as up-to-date documentation +- Disaster recovery: Rapidly restore infrastructure after failures + +#### Benefits for managing repos with IaC +- Repeatability: Easily spin up identical repositories for different stages or teams +- Change history: All configuration changes are tracked in Git +- Peer review: Repository settings can be reviewed and approved like code +- Automation: Apply bulk updates to many repositories at once +- Security: Enforce consistent security policies across all repos \ No newline at end of file diff --git a/docs/proof.png b/docs/proof.png new file mode 100644 index 0000000000..e8dafc79a0 Binary files /dev/null and b/docs/proof.png differ diff --git a/pulumi/.gitignore b/pulumi/.gitignore new file mode 100644 index 0000000000..5f01950ec5 --- /dev/null +++ b/pulumi/.gitignore @@ -0,0 +1,5 @@ +# Pulumi +venv/ +__pycache__/ +Pulumi.*.yaml +*.pyc diff --git a/pulumi/Pulumi.yaml b/pulumi/Pulumi.yaml new file mode 100644 index 0000000000..cbe8f5841e --- /dev/null +++ b/pulumi/Pulumi.yaml @@ -0,0 +1,3 @@ +name: lab04-pulumi +description: Pulumi project for Lab 04 (Yandex Cloud VM) +runtime: python diff --git a/pulumi/__main__.py b/pulumi/__main__.py new file mode 100644 index 0000000000..b00aa4ea88 --- /dev/null +++ b/pulumi/__main__.py @@ -0,0 +1,53 @@ +import pulumi +import pulumi_yandex as yandex +from pulumi import Config + +config = Config() +import time +zone = config.get("zone") or "ru-central1-a" +folder_id = config.require("folder_id") +my_ip = config.require("my_ip") +ssh_user = config.get("ssh_user") or "ubuntu" +ssh_pub_path = config.get("ssh_public_key_path") or "~/.ssh/id_rsa.pub" +unique_suffix = str(int(time.time())) + +# Network +network = yandex.VpcNetwork(f"lab-network-{unique_suffix}", name=f"lab-vpc-{unique_suffix}", folder_id=folder_id) + +subnet = yandex.VpcSubnet( + f"lab-subnet-{unique_suffix}", + name=f"lab-subnet-{unique_suffix}", + zone=zone, + network_id=network.id, + v4_cidr_blocks=["10.10.0.0/24"], + folder_id=folder_id, +) + +# Security group +sg = yandex.VpcSecurityGroup( + "lab-sg", + name="lab-sg", + network_id=network.id, + folder_id=folder_id, + ingresses=[ + yandex.VpcSecurityGroupIngressArgs(description="ssh", protocol="TCP", port=22, v4_cidr_blocks=[my_ip]), + yandex.VpcSecurityGroupIngressArgs(description="http", protocol="TCP", port=80, v4_cidr_blocks=["0.0.0.0/0"]), + yandex.VpcSecurityGroupIngressArgs(description="app5000", protocol="TCP", port=5000, v4_cidr_blocks=["0.0.0.0/0"]), + ], +) + +# Get image for compute instance +image = yandex.get_compute_image(family="ubuntu-2204-lts") + +# Create compute instance +vm = yandex.ComputeInstance( + "lab-vm", + name="lab-vm", + zone=zone, + resources=yandex.ComputeInstanceResourcesArgs(cores=2, core_fraction=20, memory=1), + boot_disk=yandex.ComputeInstanceBootDiskArgs(initialize_params=yandex.ComputeInstanceBootDiskInitializeParamsArgs(image_id=image.id, size=10, type="network-hdd")), + network_interfaces=[yandex.ComputeInstanceNetworkInterfaceArgs(subnet_id=subnet.id, nat=True)], + metadata={"ssh-keys": f"{ssh_user}:{open("/Users/sayfetik/.ssh/id_rsa.pub").read().strip()}"}, +) + +pulumi.export("public_ip", vm.network_interfaces[0].nat_ip_address) diff --git a/pulumi/requirements.txt b/pulumi/requirements.txt new file mode 100644 index 0000000000..d456e78758 --- /dev/null +++ b/pulumi/requirements.txt @@ -0,0 +1,3 @@ +pulumi>=3.0.0,<4.0.0 +pulumi-yandex>=0.9.0 +setuptools<70 diff --git a/terraform/.gitignore b/terraform/.gitignore new file mode 100644 index 0000000000..c3033b16de --- /dev/null +++ b/terraform/.gitignore @@ -0,0 +1,12 @@ +# Terraform +*.tfstate +*.tfstate.* +.terraform/ +terraform.tfvars +*.tfvars +.terraform.lock.hcl + +# Keys / credentials +*.json +*.pem +*.key diff --git a/terraform/README.md b/terraform/README.md new file mode 100644 index 0000000000..aad054cc66 --- /dev/null +++ b/terraform/README.md @@ -0,0 +1,30 @@ +# Terraform (Lab 04) + +This directory contains Terraform configuration to create a small VM in Yandex Cloud. + +Quick steps: + +1. Install Terraform 1.9+ +2. Configure authentication (see docs/LAB04.md) +3. Create `terraform.tfvars` with `folder_id`, `my_ip` (and optionally override `zone`) +4. Run: + +```bash +terraform init +terraform fmt +terraform validate +terraform plan -out=plan.out +terraform apply "plan.out" +``` + +After apply, get the public IP: + +```bash +terraform output public_ip +``` + +To destroy: + +```bash +terraform destroy +``` diff --git a/terraform/github.tf b/terraform/github.tf new file mode 100644 index 0000000000..3d89d651d5 --- /dev/null +++ b/terraform/github.tf @@ -0,0 +1,26 @@ +provider "github" { + token = var.github_token +} + +# Control creation via variable; default false to avoid accidental repo creation +resource "github_repository" "course_repo" { + count = var.create_github ? 1 : 0 + name = "DevOps-Core-Course" + description = "Course repo managed via Terraform (example)" + visibility = "public" + has_issues = true + has_wiki = false +} + +variable "github_token" { + description = "GitHub personal access token (set via env or terraform.tfvars)" + type = string + sensitive = true + default = "" +} + +variable "create_github" { + description = "Whether to create GitHub repository via Terraform" + type = bool + default = false +} diff --git a/terraform/main.tf b/terraform/main.tf new file mode 100644 index 0000000000..3e2c1bb707 --- /dev/null +++ b/terraform/main.tf @@ -0,0 +1,57 @@ +terraform { + required_version = ">= 1.0.0" + required_providers { + yandex = { + source = "yandex-cloud/yandex" + version = ">= 0.87.0" + } + github = { + source = "integrations/github" + version = ">= 4.0.0" + } + } +} + +provider "yandex" { + service_account_key_file = var.service_account_key_file + folder_id = var.folder_id +} + +data "yandex_compute_image" "ubuntu" { + family = "ubuntu-2204-lts" +} + + + +data "yandex_vpc_subnet" "lab_subnet" { + subnet_id = "e9be2kmkd88699e7ojls" +} + +resource "yandex_compute_instance" "vm" { + name = var.instance_name + platform_id = "standard-v3" + zone = var.zone + + resources { + cores = 2 + core_fraction = 20 + memory = 1 + } + + boot_disk { + initialize_params { + image_id = data.yandex_compute_image.ubuntu.id + size = 10 + type = "network-hdd" + } + } + + network_interface { + subnet_id = data.yandex_vpc_subnet.lab_subnet.id + nat = true + } + + metadata = { + ssh-keys = "ubuntu:${var.ssh_public_key}" + } +} \ No newline at end of file diff --git a/terraform/outputs.tf b/terraform/outputs.tf new file mode 100644 index 0000000000..89b2aae25a --- /dev/null +++ b/terraform/outputs.tf @@ -0,0 +1,7 @@ +output "instance_id" { + value = yandex_compute_instance.vm.id +} + +output "public_ip" { + value = yandex_compute_instance.vm.network_interface[0].nat_ip_address +} diff --git a/terraform/plan.out b/terraform/plan.out new file mode 100644 index 0000000000..8f873819cc Binary files /dev/null and b/terraform/plan.out differ diff --git a/terraform/variables.tf b/terraform/variables.tf new file mode 100644 index 0000000000..431f3c4bc9 --- /dev/null +++ b/terraform/variables.tf @@ -0,0 +1,28 @@ +variable "folder_id" { + description = "Yandex Cloud folder id" + type = string +} + +variable "zone" { + description = "Yandex Cloud zone" + type = string + default = "ru-central1-a" +} + +variable "instance_name" { + description = "Name for the compute instance" + type = string + default = "lab4" +} + +variable "ssh_public_key" { + description = "Your SSH public key content" + type = string + sensitive = true +} + +variable "service_account_key_file" { + description = "Path to Yandex Cloud service account key JSON file" + type = string + default = "~/.config/yandex-cloud/sa-key.json" +}