Lab02

app_go/.dockerignore

@@ -0,0 +1,43 @@
+# Go artifacts
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+*.test
+*.out
+*.o
+*.prof
+*.trace
+vendor/
+__pycache__/
+
+# Git
+.git/
+.gitignore
+
+# IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Documentation
+*.md
+docs/
+README.md
+
+# Docker
+Dockerfile*
+docker-compose*
+.dockerignore
+
+# Temporary files
+*.tmp
+*.log
+tmp/
+logs/

app_go/Dockerfile

@@ -0,0 +1,42 @@
+# Stage 1: Builder - full build environment
+FROM golang:1.21-alpine AS builder
+
+# Install system dependencies for build (git for go mod download)
+RUN apk add --no-cache git ca-certificates
+
+# Set working directory
+WORKDIR /app
+
+# Copy Go module files
+COPY go.mod ./
+
+# Download Go module dependencies
+RUN go mod download
+
+# Copy application source code
+COPY . .
+
+# Build Go application with optimizations
+RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build \
+    -a \
+    -ldflags="-w -s -extldflags '-static'" \
+    -o devops-info-service .
+
+# Stage 2: Minimal runtime
+FROM scratch
+
+# Copy CA certificates from builder for HTTPS support
+COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
+
+# Copy the compiled binary from builder
+COPY --from=builder /app/devops-info-service /app/devops-info-service
+
+# Expose port
+EXPOSE 5000
+
+# Set environment variables
+ENV HOST=0.0.0.0
+ENV PORT=5000
+
+# Run the application
+CMD ["/app/devops-info-service"]

app_go/README.md

@@ -0,0 +1,97 @@
+# DevOps Info Service (Go)
+## Overview
+A Go-based web service designed to furnish details about itself and its operational environment. This compiled version of the service is optimized for containerization and multi-stage Docker builds, offering improved performance and smaller deployment footprints compared to interpreted languages.
+
+## Prerequisites
+- Go 1.21 or higher
+- Git (for dependency management)
+
+## Installation
+1. Clone repository:
+
+```bash
+# Clone the project
+git clone https://github.com/s3rap1s/DevOps-Core-Course.git
+cd DevOps-Core-Course/app_go
+
+# Download dependencies
+go mod download
+
+# Build the application
+go build -o devops-info-service
+```
+
+## Running the Application
+```bash
+# Default configuration
+./devops-info-service
+
+# With custom port
+PORT=8080 ./devops-info-service
+
+# With custom port and host
+HOST=127.0.0.1 PORT=3000 ./devops-info-service
+
+# Run directly without building
+go run main.go
+Building for Different Platforms
+bash
+# Build for current platform
+go build -o devops-info-service
+```
+
+## API Endpoints
+### GET /
+Return comprehensive service and system information:
+
+```json
+{
+  "service": {
+    "name": "devops-info-service",
+    "version": "1.0.0",
+    "description": "DevOps course info service",
+    "framework": "Go"
+  },
+  "system": {
+    "hostname": "my-laptop",
+    "platform": "linux",
+    "platform_version": "Linux Kernel",
+    "architecture": "amd64",
+    "cpu_count": 8,
+    "go_version": "go1.21.4"
+  },
+  "runtime": {
+    "uptime_seconds": 3600,
+    "uptime_human": "1 hour, 0 minutes",
+    "current_time": "2026-01-07T14:30:00.000Z",
+    "timezone": "UTC"
+  },
+  "request": {
+    "client_ip": "127.0.0.1:12345",
+    "user_agent": "curl/7.81.0",
+    "method": "GET",
+    "path": "/"
+  },
+  "endpoints": [
+    {"path": "/", "method": "GET", "description": "Service information"},
+    {"path": "/health", "method": "GET", "description": "Health check"}
+  ]
+}
+```
+
+### GET /health
+Simple health endpoint for monitoring:
+
+```json
+{
+  "status": "healthy",
+  "timestamp": "2024-01-15T14:30:00.000Z",
+  "uptime_seconds": 3600
+}
+```
+
+## Configuration
+| Variable | Default   | Description                  |
+| -------- | --------- | ---------------------------- |
+| `HOST`   | `0.0.0.0` | Network interface to bind    |
+| `PORT`   | `5000`    | Port to listen on            |

app_go/docs/GO.md

@@ -0,0 +1,18 @@
+# Language Justification
+## My Choice: Go
+I selected **Go** as the compiled language for the bonus task implementation. Here's why:
+
+**Comparison Table:**
+
+| Criteria | Go	| Rust | Java | C# |
+|----------|----|------|------|----|
+|Learning Curve | Low | High | Medium | Medium |
+|Development Speed | High | Low | Medium | Medium |
+|Standard Library | Excellent | Good | Extensive | Extensive |
+|Performance | Excellent | Outstanding | Good | Good |
+|Binary Size | ~7 MB | ~3 MB | ~40 MB | ~30 MB |
+|Memory Safety | GC | Compile-time | GC | GC |
+| **Choice for Bonus** | **✓** | | | |			
+
+**Justification:**
+Go offers the perfect balance for a DevOps service: it compiles to a single static binary with no runtime dependencies, has excellent concurrency support, and provides a rich standard library including HTTP server functionality. Its simplicity and fast compilation make it ideal for the iterative development required in this course. Go is also widely used in the DevOps ecosystem (Docker, Kubernetes, Prometheus), making it a relevant choice.