This is a parser for HTTP messages written in Swift 3. It parses both requests and responses. The parser is designed to be used in performance HTTP applications. It does not make any allocations, it does not buffer data and it can be interrupted at anytime.
This project was forked and ported from the 'C' http-parser project.
Features:
- No dependencies
- Handles persistent streams (keep-alive)
- Decodes chunked encoding
- Upgrade support
- Defends against buffer overflow attacks
The parser extracts the following information from HTTP messages:
- Header fields and values
- Content-Length
- Request method
- Response status code
- Transfer-Encoding
- HTTP version
- Request URL
- Message body
- Leverage the existing 'C' logic from http-parser
- Allow for http-parser.c changes to be easily ported in the future. As such:
- Intentionally not adopting Swift naming guidelines
- Keep all variable and function names the same
- Only change public API's to be object oriented
- Leave unnecessary markup in place such as:
- End of case 'break'
- Parenthesis in if statements
The Swift version is currently 1.4 times slower than the 'C' version. However the library is processing over 500,000 requests per second which should meet the requirements of most performance Swift applications.
Tests run with Release mode on a MacBook Air (MacBookAir6,2):
- http-parser - 'C' - 782K req/sec
- HTTPParser - Swift - 566K req/sec
Although all memory allocations have been optimized out there still are several retain/release calls which could be optimized. It would be ideal for an expert in the Xcode Instruments Time Profiler to review the library.
| http-parser | HTTPParser |
|---|---|
| struct http_parser | class http_parser |
| struct http_parser_settings | protocol http_parser_delegate |
| http_parser_version() | version() |
| http_parser_init() | reset() |
| http_parser_settings_init() | Use protocol above |
| http_parser_execute() | execute() |
| http_should_keep_alive() | should_keep_alive() |
| http_method_str() | method_str() |
| http_errno_name() | errno_name() |
| http_errno_description() | errno_description() |
| http_parser_pause() | pause() |
| http_body_is_final() | body_is_final() |
| http_parser_url_init() | Not ported - see below |
| http_parser_parse_url() | Not ported - see below |
macOS
- Install Xcode 8.1
- run 'swift build --clean'
- run 'swift build'
- run 'swift test'
Linux
- Install Docker for Mac v1.12
- run 'docker-compose up'
- Finish porting unit tests (test.swift)
- Further Xcode Instruments Time Profiler review
The URL parsing code from http-parser was not ported since Swift 3 applications can rely on the native URL class in Foundation.