Yaws is an HTTP/1.1 web server written in Erlang and designed particularly for dynamic web applications.
It can serve conventional static content, but its main strength is integrating web requests with Erlang code and the concurrency model of the Erlang runtime. Yaws can run as a standalone server or be embedded inside a larger Erlang application, where its processes can operate under the host application’s supervision tree. The project also provides facilities for common web protocols and application patterns without requiring a separate stack of components.
This is free and open source software.
Key Features
- Serves static files and dynamically generated .yaws pages.
- Supports HTTPS through Erlang’s SSL facilities.
- Provides WebSocket support compliant with RFC 6455.
- Supports server-sent events and long-polling applications.
- Offers full streaming for uploads and dynamically generated downloads.
- Caches commonly accessed pages in RAM.
- Provides cookie-based session APIs and persistent cookie handling.
- Supports HTTP authentication for protected resources.
- Runs CGI programs and can invoke PHP through php-cgi.
- Provides application modules for mapping virtual paths to Erlang modules.
- Supports multiple virtual servers through its configuration system.
- Offers forward and reverse proxy functionality.
- Can be embedded within another Erlang application rather than run as an independent server.
- Supports configurable request rewriting and custom error handling.
- Provides examples for AJAX and JSON-RPC, file uploads, forms, redirects, streaming data and WebSockets.
- Can be built with either Autotools or rebar3.
- Supports deterministic builds for reproducible packaging.
- Can run as a daemon and use Erlang heart functionality to restart after a crash or hang.
- Requires Erlang/OTP 25.0 or later when compiling current source.
Website: github.com/erlyaws/yaws
Support:
Developer: Yaws developers
License: BSD 3-Clause License
Yaws is written in Erlang. Learn Erlang with our recommended free books and free tutorials.
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