RestSharp

Overview

RestSharp is a lightweight HTTP API client library for .NET that wraps HttpClient to simplify making synchronous and asynchronous calls to REST and other HTTP APIs. It handles parameter addition (query, URL segments, forms, bodies), serialization to JSON/XML, content headers, and response deserialization, targeting .NET developers working with external APIs.³⁷

Key Features

• Typed API Clients - Create configurable, interface-based proxy clients for APIs with default parameters.
• Parameter Handling - Supports query, URL segment, form, body, header, and file attachment parameters.
• Serialization/Deserialization - Serializes request payloads and deserializes responses to/from JSON or XML.
• HTTP Methods - Handles GET, POST, PUT, etc., with automatic content type and form handling.
• Default Parameters - Adds parameters to all requests from the client instance.
• Async Support - Provides asynchronous HTTP calls over HTTP.
• File Uploads - Supports multipart/form-data for file attachments.

Pricing

Platforms & Requirements

RestSharp runs on .NET platforms including .NET Framework, .NET Core, and .NET 5+, compatible with Windows, macOS, and Linux where .NET is supported. No specific minimum requirements beyond .NET runtime; wraps HttpClient so inherits its platform support. Limitations follow .NET ecosystem, e.g., no native mobile without .NET MAUI.

Integrations & Ecosystem

• HttpClient (core wrapper)
• JSON serializers (e.g., Newtonsoft.Json, System.Text.Json)
• XML serializers
• NuGet package manager
• ASP.NET Core applications
• OAuth (via examples)
• SpecFlow for testing
• Microservices APIs

Alternatives

Reputation

RestSharp is widely used in the .NET community for simplifying HTTP API calls, praised for ease of parameter handling and serialization since 2008.⁵⁷ Criticisms include outdated patterns in newer versions favoring direct HttpClient use, with some deprecation of legacy features.² It remains active with ongoing updates and strong GitHub presence.⁷