restsharp/RestSharp

# CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

## Build & Test Commands

```bash
# Build
dotnet build RestSharp.slnx -c Debug

# Run all tests
dotnet test RestSharp.slnx -c Debug

# Run tests for a specific TFM
dotnet test RestSharp.slnx -f net9.0

# Run a single test by fully-qualified name
dotnet test test/RestSharp.Tests/RestSharp.Tests.csproj --filter "FullyQualifiedName=RestSharp.Tests.ObjectParserTests.ShouldUseRequestProperty" -f net8.0

# Pack
dotnet pack src/RestSharp/RestSharp.csproj -c Release -o nuget -p:IncludeSymbols=true -p:SymbolPackageFormat=snupkg
```

**Note:** `dotnet test` with `.slnx` does not work with `net8.0`. To run tests targeting `net8.0`, use individual project files: `dotnet test test/RestSharp.Tests/RestSharp.Tests.csproj -f net8.0`

## Project Overview

RestSharp is a lightweight HTTP API client library for .NET that wraps `HttpClient`. It provides default parameters, multiple parameter types (query, URL segment, header, cookie, body), built-in JSON/XML/CSV serialization, and authentication support.

### Repository Layout

- `src/RestSharp/` — Core library
- `src/RestSharp.Serializers.NewtonsoftJson/` — Newtonsoft.Json serializer adapter
- `src/RestSharp.Serializers.Xml/` — Custom XML serializer
- `src/RestSharp.Serializers.CsvHelper/` — CsvHelper serializer adapter
- `src/RestSharp.Extensions.DependencyInjection/` — DI integration
- `gen/SourceGenerator/` — Custom incremental source generators
- `test/RestSharp.Tests/` — Unit tests
- `test/RestSharp.Tests.Integrated/` — Integration tests (WireMock-based)
- `test/RestSharp.Tests.Serializers.*/` — Serializer-specific tests

## Architecture

### Core Classes

- **RestClient** (`RestClient.cs`, split into partials `RestClient.*.cs`) — Main entry point. Wraps `HttpClient`, holds `ReadOnlyRestClientOptions`, `RestSerializers`, and `DefaultParameters`. Thread-safe when configured via `RestClientOptions`.
- **RestRequest** (`Request/RestRequest.cs`) — Request container with fluent API via extension methods in `RestRequest*.cs` files. Parameters split by type: query, body, header, URL segment, cookie, file.
- **RestResponse / RestResponse\<T\>** (`Response/RestResponse*.cs`) — Response containers with public setters. `[GenerateClone]` generates a static factory to copy base properties from `RestResponse` into `RestResponse<T>`.
- **RestClientOptions** (`Options/RestClientOptions.cs`) — Mutable configuration class. An immutable `ReadOnlyRestClientOptions` wrapper is generated by `[GenerateImmutable]`.

### Request Pipeline

`ExecuteAsync` → build request → interceptor chain (`BeforeRequest` → `BeforeHttpRequest` → send → `AfterHttpRequest` → `AfterRequest`) → deserialization → error handling. Interceptors are configured via `RestClientOptions.Interceptors`.

### Parameter System (`Parameters/`)

Abstract `Parameter` record base with concrete types: `HeaderParameter`, `QueryParameter`, `BodyParameter`, `UrlSegmentParameter`, `FileParameter`, `GetOrPostParameter`, `CookieParameter`. `ObjectParser` converts objects to parameters via reflection.

### Serialization (`Serializers/`)

`ISerializer`/`IDeserializer` interfaces. `RestSerializers` manages serializers by `DataFormat` enum (Json, Xml, Csv). Default: `SystemTextJsonSerializer`. Configured via `ConfigureSerialization` delegate in client constructors.

### Authentication (`Authenticators/`)

`IAuthenticator` with single `Authenticate(IRestClient, RestRequest)` method. Built-in: `HttpBasicAuthenticator`, `JwtAuthenticator`, OAuth1/OAuth2 authenticators. Set via `RestClientOptions.Authenticator`.

### Source Generators (`gen/SourceGenerator/`)

- `[GenerateImmutable]` — Creates read-only wrapper (used on `RestClientOptions`)
- `[GenerateClone]` — Creates static factory clone methods (used on `RestResponse<T>`)
- `[Exclude]` — Excludes properties from immutable generation
- Generator target must be `netstandard2.0`. Inspect output in `obj/<Config>/<TFM>/generated/SourceGenerator/`.

## Multi-Targeting

**Library:** `netstandard2.0`, `net471`, `net48`, `net8.0`, `net9.0`, `net10.0`
**Tests:** `net48` (Windows only), `net8.0`, `net9.0`, `net10.0`

Use conditional compilation for TFM-specific APIs: `#if NET`, `#if NET8_0_OR_GREATER`. `System.Text.Json` is a NuGet dependency on older TFMs but built-in on net8.0+.

## Code Style & Conventions

- **C# version:** preview (latest features)
- **Nullable:** Enabled in `/src`, disabled in `/test`
- **License header required** in all `/src` files (Apache-2.0, see `.github/copilot-instructions.md` for exact text)
- **Strong-named** assemblies via `RestSharp.snk`
- **Partial classes** for large types, linked via `<DependentUpon>` in csproj
- **Package versions** centrally managed in `Directory.Packages.props` — don't pin in individual projects
- **Versioning** via MinVer from git tags (no hardcoded versions)
- Follow `.editorconfig` for formatting

## Testing

- **Stack:** xUnit + FluentAssertions + AutoFixture
- **HTTP mocking:** WireMock.Net (avoid live endpoints)
- Global usings in test projects: `Xunit`, `FluentAssertions`, `AutoFixture`
- Guard TFM-specific tests with `#if NET8_0_OR_GREATER`
- Test results: `test-results/<TFM>/<ProjectName>.trx`

## Documentation

Docusaurus 3 site in `docs/`. Dev server: `cd docs && pnpm start`. See [DOCUMENTATION.md](DOCUMENTATION.md) for full details on structure, versioning, and writing docs.

## Working with Issues

- Avoid changing default behavior unless absolutely necessary
- Avoid breaking the existing API
- Leave existing tests intact to catch regressions; add new tests for fixed cases