async-http-client

# Async Http Client

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AsyncHttpClient (AHC) is a high-performance, asynchronous HTTP client for Java
built on top of [Netty](https://github.com/netty/netty).
It supports HTTP/1.1, HTTP/2, and WebSocket protocols.

## Table of Contents

- [Features](#features)
- [Requirements](#requirements)
- [Installation](#installation)
- [Quick Start](#quick-start)
- [Configuration](#configuration)
- [HTTP Requests](#http-requests)
- [Handling Responses](#handling-responses)
- [HTTP/2](#http2)
- [WebSocket](#websocket)
- [Authentication](#authentication)
- [Proxy Support](#proxy-support)
- [Community](#community)
- [License](#license)

## Features

- **HTTP/2 with multiplexing** — enabled by default over TLS via ALPN,
  with connection multiplexing and GOAWAY handling
- **HTTP/1.1 and HTTP/1.0** — connection pooling and keep-alive
- **WebSocket** — text, binary, and ping/pong frame support
- **Asynchronous API** — non-blocking I/O with `ListenableFuture`
  and `CompletableFuture`
- **Compression** — automatic gzip, deflate, Brotli, and Zstd decompression
- **Authentication** — Basic, Digest, NTLM, SPNEGO/Kerberos, and SCRAM-SHA-256
- **Proxy** — HTTP, SOCKS4, and SOCKS5 with CONNECT tunneling
- **Native transports** — optional Epoll, KQueue, and io_uring
- **Request/response filters** — intercept and transform at each stage
- **Cookie management** — RFC 6265-compliant cookie store
- **Multipart uploads** — file, byte array, input stream, and string parts
- **Resumable downloads** — built-in `ResumableIOExceptionFilter`

## Requirements

Java 11+

## Installation

**Maven:**

```xml
<dependency>
    <groupId>org.asynchttpclient</groupId>
    <artifactId>async-http-client</artifactId>
    <version>3.0.14</version>
</dependency>
```

**Gradle:**

```groovy
implementation 'org.asynchttpclient:async-http-client:3.0.14'
```

<details>
<summary><b>Optional: Native Transport</b></summary>

For lower-latency I/O on Linux, add a native transport dependency:

```xml
<!-- Epoll (Linux) -->
<dependency>
    <groupId>io.netty</groupId>
    <artifactId>netty-transport-native-epoll</artifactId>
    <classifier>linux-x86_64</classifier>
</dependency>

<!-- io_uring (Linux) -->
<dependency>
    <groupId>io.netty</groupId>
    <artifactId>netty-transport-native-io_uring</artifactId>
    <classifier>linux-x86_64</classifier>
</dependency>
```

Then enable in config:

```java
AsyncHttpClient client = asyncHttpClient(config().setUseNativeTransport(true));
```

</details>

<details>
<summary><b>Optio