Adds linting tools and finishes Users.list

.credo.exs

@@ -0,0 +1,223 @@
+# This file contains the configuration for Credo and you are probably reading
+# this after creating it with `mix credo.gen.config`.
+#
+# If you find anything wrong or unclear in this file, please report an
+# issue on GitHub: https://github.com/rrrene/credo/issues
+#
+%{
+  #
+  # You can have as many configs as you like in the `configs:` field.
+  configs: [
+    %{
+      #
+      # Run any config using `mix credo -C <name>`. If no config name is given
+      # "default" is used.
+      #
+      name: "default",
+      #
+      # These are the files included in the analysis:
+      files: %{
+        #
+        # You can give explicit globs or simply directories.
+        # In the latter case `**/*.{ex,exs}` will be used.
+        #
+        included: [
+          "examples/",
+          "lib/",
+          "src/",
+          "test/"
+        ],
+        excluded: [~r"/lib/mix", ~r"/_build/", ~r"/deps/", ~r"/node_modules/"]
+      },
+      #
+      # Load and configure plugins here:
+      #
+      plugins: [],
+      #
+      # If you create your own checks, you must specify the source files for
+      # them here, so they can be loaded by Credo before running the analysis.
+      #
+      requires: [],
+      #
+      # If you want to enforce a style guide and need a more traditional linting
+      # experience, you can change `strict` to `true` below:
+      #
+      strict: true,
+      #
+      # To modify the timeout for parsing files, change this value:
+      #
+      parse_timeout: 5000,
+      #
+      # If you want to use uncolored output by default, you can change `color`
+      # to `false` below:
+      #
+      color: true,
+      #
+      # You can customize the parameters of any check by adding a second element
+      # to the tuple.
+      #
+      # To disable a check put `false` as second element:
+      #
+      #     {Credo.Check.Design.DuplicatedCode, false}
+      #
+      checks: %{
+        enabled: [
+          #
+          ## Consistency Checks
+          #
+          {Credo.Check.Consistency.ExceptionNames, []},
+          {Credo.Check.Consistency.LineEndings, []},
+          {Credo.Check.Consistency.ParameterPatternMatching, []},
+          {Credo.Check.Readability.ParenthesesOnZeroArityDefs, []},
+          {Credo.Check.Consistency.SpaceAroundOperators, []},
+          {Credo.Check.Consistency.SpaceInParentheses, []},
+          {Credo.Check.Consistency.TabsOrSpaces, []},
+
+          #
+          ## Design Checks
+          #
+          # You can customize the priority of any check
+          # Priority values are: `low, normal, high, higher`
+          #
+          {Credo.Check.Design.AliasUsage,
+           [priority: :normal, if_nested_deeper_than: 1, if_called_more_often_than: 0]},
+          {Credo.Check.Design.TagFIXME, []},
+          # You can also customize the exit_status of each check.
+          # If you don't want TODO comments to cause `mix credo` to fail, just
+          # set this value to 0 (zero).
+          #
+          {Credo.Check.Design.TagTODO, [exit_status: 2]},
+
+          #
+          ## Readability Checks
+          #
+          {Credo.Check.Readability.AliasOrder, []},
+          {Credo.Check.Readability.FunctionNames, []},
+          {Credo.Check.Readability.LargeNumbers, []},
+          {Credo.Check.Readability.MaxLineLength, [priority: :low, max_length: 120]},
+          {Credo.Check.Readability.ModuleAttributeNames, []},
+          {Credo.Check.Readability.ModuleDoc, []},
+          {Credo.Check.Readability.ModuleNames, []},
+          {Credo.Check.Readability.ParenthesesInCondition, []},
+          # {Credo.Check.Readability.ParenthesesOnZeroArityDefs, []},
+          {Credo.Check.Readability.PipeIntoAnonymousFunctions, []},
+          {Credo.Check.Readability.PredicateFunctionNames, []},
+          {Credo.Check.Readability.PreferImplicitTry, []},
+          {Credo.Check.Readability.RedundantBlankLines, []},
+          {Credo.Check.Readability.Semicolons, []},
+          {Credo.Check.Readability.SpaceAfterCommas, []},
+          {Credo.Check.Readability.StringSigils, []},
+          {Credo.Check.Readability.TrailingBlankLine, []},
+          {Credo.Check.Readability.TrailingWhiteSpace, []},
+          {Credo.Check.Readability.UnnecessaryAliasExpansion, []},
+          {Credo.Check.Readability.VariableNames, []},
+          {Credo.Check.Readability.WithSingleClause, []},
+
+          #
+          ## Refactoring Opportunities
+          #
+          {Credo.Check.Refactor.Apply, []},
+          {Credo.Check.Refactor.CondStatements, []},
+          {Credo.Check.Refactor.CyclomaticComplexity, []},
+          {Credo.Check.Refactor.FilterCount, []},
+          {Credo.Check.Refactor.FilterFilter, []},
+          {Credo.Check.Refactor.FunctionArity, []},
+          {Credo.Check.Refactor.LongQuoteBlocks, []},
+          {Credo.Check.Refactor.MapJoin, []},
+          {Credo.Check.Refactor.MatchInCondition, []},
+          {Credo.Check.Refactor.NegatedConditionsInUnless, []},
+          {Credo.Check.Refactor.NegatedConditionsWithElse, []},
+          {Credo.Check.Refactor.Nesting, []},
+          {Credo.Check.Refactor.RedundantWithClauseResult, []},
+          {Credo.Check.Refactor.RejectReject, []},
+          {Credo.Check.Refactor.UnlessWithElse, []},
+          {Credo.Check.Refactor.WithClauses, []},
+
+          #
+          ## Warnings
+          #
+          {Credo.Check.Warning.ApplicationConfigInModuleAttribute, []},
+          {Credo.Check.Warning.BoolOperationOnSameValues, []},
+          {Credo.Check.Warning.Dbg, []},
+          {Credo.Check.Warning.ExpensiveEmptyEnumCheck, []},
+          {Credo.Check.Warning.IExPry, []},
+          {Credo.Check.Warning.IoInspect, []},
+          {Credo.Check.Warning.MissedMetadataKeyInLoggerConfig, []},
+          {Credo.Check.Warning.OperationOnSameValues, []},
+          {Credo.Check.Warning.OperationWithConstantResult, []},
+          {Credo.Check.Warning.RaiseInsideRescue, []},
+          {Credo.Check.Warning.SpecWithStruct, []},
+          {Credo.Check.Warning.UnsafeExec, []},
+          {Credo.Check.Warning.UnusedEnumOperation, []},
+          {Credo.Check.Warning.UnusedFileOperation, []},
+          {Credo.Check.Warning.UnusedKeywordOperation, []},
+          {Credo.Check.Warning.UnusedListOperation, []},
+          {Credo.Check.Warning.UnusedPathOperation, []},
+          {Credo.Check.Warning.UnusedRegexOperation, []},
+          {Credo.Check.Warning.UnusedStringOperation, []},
+          {Credo.Check.Warning.UnusedTupleOperation, []},
+          {Credo.Check.Warning.WrongTestFileExtension, []},
+
+          # Enabled controversial and experimental checks
+          {Credo.Check.Consistency.UnusedVariableNames, []},
+          {Credo.Check.Design.DuplicatedCode, []},
+          {Credo.Check.Readability.ImplTrue, []},
+          {Credo.Check.Readability.Specs, []},
+          {Credo.Check.Readability.StrictModuleLayout, []},
+          {Credo.Check.Refactor.IoPuts, []},
+          {Credo.Check.Warning.MixEnv, []}
+        ],
+        disabled: [
+          #
+          # Checks scheduled for next check update (opt-in for now)
+          {Credo.Check.Refactor.UtcNowTruncate, []},
+
+          #
+          # Controversial and experimental checks (opt-in, just move the check to `:enabled`
+          #   and be sure to use `mix credo --strict` to see low priority checks)
+          #
+          {Credo.Check.Consistency.MultiAliasImportRequireUse, []},
+          # {Credo.Check.Consistency.UnusedVariableNames, []},
+          # {Credo.Check.Design.DuplicatedCode, []},
+          {Credo.Check.Design.SkipTestWithoutComment, []},
+          {Credo.Check.Readability.AliasAs, []},
+          {Credo.Check.Readability.BlockPipe, []},
+          # {Credo.Check.Readability.ImplTrue, []},
+          {Credo.Check.Readability.MultiAlias, []},
+          {Credo.Check.Readability.NestedFunctionCalls, []},
+          {Credo.Check.Readability.OneArityFunctionInPipe, []},
+          {Credo.Check.Readability.OnePipePerLine, []},
+          {Credo.Check.Readability.SeparateAliasRequire, []},
+          {Credo.Check.Readability.SingleFunctionToBlockPipe, []},
+          {Credo.Check.Readability.SinglePipe, []},
+          # {Credo.Check.Readability.Specs, []},
+          # {Credo.Check.Readability.StrictModuleLayout, []},
+          {Credo.Check.Readability.WithCustomTaggedTuple, []},
+          {Credo.Check.Refactor.ABCSize, []},
+          {Credo.Check.Refactor.AppendSingleItem, []},
+          {Credo.Check.Refactor.DoubleBooleanNegation, []},
+          {Credo.Check.Refactor.FilterReject, []},
+          # {Credo.Check.Refactor.IoPuts, []},
+          {Credo.Check.Refactor.MapMap, []},
+          {Credo.Check.Refactor.ModuleDependencies, []},
+          {Credo.Check.Refactor.NegatedIsNil, []},
+          {Credo.Check.Refactor.PassAsyncInTestCases, []},
+          {Credo.Check.Refactor.PipeChainStart, []},
+          {Credo.Check.Refactor.RejectFilter, []},
+          {Credo.Check.Refactor.VariableRebinding, []},
+          {Credo.Check.Warning.LazyLogging, []},
+          {Credo.Check.Warning.LeakyEnvironment, []},
+          {Credo.Check.Warning.MapGetUnsafePass, []},
+          # {Credo.Check.Warning.MixEnv, []},
+          {Credo.Check.Warning.UnsafeToAtom, []}
+
+          # {Credo.Check.Refactor.MapInto, []},
+
+          #
+          # Custom checks can be created using `mix credo.gen.check`.
+          #
+        ]
+      }
+    }
+  ]
+}

.iex.exs

@@ -0,0 +1,7 @@
+creds = %{
+  client_id: System.fetch_env!("MICROSOFT_CLIENT_ID"),
+  client_secret: System.fetch_env!("MICROSOFT_CLIENT_SECRET"),
+  tenant_id: System.fetch_env!("MICROSOFT_TENANT_ID")
+}
+
+client = Msg.Client.new(creds)

.markdownlint.json

@@ -0,0 +1,37 @@
+{
+  "default": true,
+  "gitignore": true,
+  "ignores": [
+    "node_modules/"
+  ],
+  "line-length": false,
+  "no-duplicate-heading": false,
+  "no-inline-html": {
+    "allowed_elements": ["br", "kbd", "sub", "sup"]
+  },
+  "whitespace": true,
+  "no-hard-tabs": true,
+  "no-trailing-spaces": true,
+  "no-multiple-blanks": {
+    "maximum": 2
+  },
+  "blanks-around-headings": {
+    "lines_above": 1,
+    "lines_below": 1
+  },
+  "heading-increment": true,
+  "no-missing-space-atx": true,
+  "no-missing-space-closed-atx": true,
+  "ul-style": {
+    "style": "dash"
+  },
+  "ol-prefix": {
+    "style": "one_or_ordered"
+  },
+  "list-indent": true,
+  "blanks-around-fences": true,
+  "fenced-code-language": true,
+  "first-line-h1": false,
+  "heading-start-left": true,
+  "single-trailing-newline": true
+}

CLAUDE.md

@@ -0,0 +1,84 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+This is `msg`, an Elixir library for accessing Microsoft 365 data using the Microsoft Graph API. It's designed specifically for applications using OAuth2 client credentials flow (application-only authentication).
+
+## Development Commands
+
+```bash
+# Install dependencies
+mix deps.get
+
+# Run tests
+mix test
+
+# Run tests with coverage
+mix coveralls
+
+# Format code
+mix format
+
+# Generate documentation (docs environment)
+mix docs
+
+# Run comprehensive quality checks
+mix quality
+
+# Skip slow Dialyzer step in quality check
+mix quality --skip-dialyzer
+
+# Run static analysis only
+mix credo --strict
+
+# Run type checking
+mix dialyzer
+
+# Run a single test file
+mix test test/path/to/test_file.exs
+
+# Run integration tests
+mix test test/msg/integration/
+```
+
+## Quality Standards
+
+This project enforces strict code quality via the `mix quality` task (`lib/mix/tasks/quality.ex:1`), which runs:
+
+- Code formatting (auto-fixed)
+- Trailing whitespace removal (auto-fixed)
+- Markdown linting (auto-fixed if markdownlint-cli2 available)
+- Test coverage check (requires >90%)
+- Static analysis with Credo in strict mode
+- Type checking with Dialyzer
+
+## Architecture
+
+The library follows a layered architecture:
+
+- **Msg.Client** (`lib/msg/client.ex:1`): Handles OAuth2 authentication and creates configured Req clients with Bearer tokens for Graph API requests
+- **Msg.Request** (`lib/msg/request.ex:1`): Provides low-level HTTP request helpers with response handling and error parsing
+- **Msg.Users** (`lib/msg/users.ex:1`): Higher-level API wrapper for `/users` endpoints - pattern for other Graph API modules
+
+### Key Dependencies
+
+- **Req**: HTTP client for making API requests
+- **OAuth2**: Client credentials flow implementation
+- **Jason**: JSON encoding/decoding
+- **Mox**: Test mocking framework
+- **Credo**: Static code analysis
+- **Dialyzer**: Type checking
+- **ExCoveralls**: Test coverage reporting
+
+### Testing Strategy
+
+The project uses ExUnit with Mox for mocking. Integration tests are separated in `test/msg/integration/` directory for real API testing scenarios. Coverage must be >90%.
+
+### Authentication Flow
+
+The library implements OAuth2 client credentials flow:
+1. `Msg.Client.new/1` accepts credentials (`client_id`, `client_secret`, `tenant_id`)
+2. `fetch_token!/1` exchanges credentials for access token via Azure AD
+3. Returns configured Req client with Authorization header for Graph API calls

README.md

@@ -35,8 +35,8 @@ client = Msg.Client.new(creds)
 
 ## Features
 
-* Built on top of Req for HTTP requests
-* OAuth2 client credentials flow via oauth2
+- Built on top of Req for HTTP requests
+- OAuth2 client credentials flow via oauth2
 
 ## License
 

coveralls.json

@@ -0,0 +1,12 @@
+{
+  "skip_files": [ "test/support", "lib/mix/tasks" ],
+  "coverage_options": {
+    "treat_no_relevant_lines_as_covered": true,
+    "output_dir": "cover/",
+    "minimum_coverage": 90,
+    "html_filter_full_covered": true
+  },
+  "terminal_options": {
+    "file_column_width": 50
+  }
+}