8effcac6f5
Added the HTTP header manipulation layer that enables span context injection into and extraction from HAProxy's HTX message buffers, completing the end-to-end context propagation path. The new http.c module implements three public functions: flt_otel_http_headers_get() extracts HTTP headers matching a name prefix from the channel's HTX buffer into an otelc_text_map structure, stripping the prefix and separator dash from header names before storage; flt_otel_http_header_set() constructs a full header name from a prefix and suffix joined by a dash, removes all existing occurrences, and optionally adds the header with a new value; and flt_otel_http_headers_remove() removes all headers matching a given prefix. A debug-only flt_otel_http_headers_dump() logs all HTTP headers from a channel at NOTICE level. The scope runner in event.c now extracts propagation contexts from HTTP headers before processing spans: for each configured extract context, it calls flt_otel_http_headers_get() to read matching headers into a text map, then passes the text map to flt_otel_scope_context_init() which extracts the OTel span context from the carrier. After span execution, the span runner injects the span context back into HTTP headers via flt_otel_inject_http_headers() followed by flt_otel_http_header_set() for each propagation key. The unused resource cleanup in flt_otel_scope_free_unused() now also removes contexts that failed extraction by deleting their associated HTTP headers via flt_otel_http_headers_remove() before freeing the scope context structure.
HAProxy
HAProxy is a free, very fast and reliable reverse-proxy offering high availability, load balancing, and proxying for TCP and HTTP-based applications.
Installation
The INSTALL file describes how to build HAProxy. A list of packages is also available on the wiki.
Getting help
The discourse and the mailing-list are available for questions or configuration assistance. You can also use the slack or IRC channel. Please don't use the issue tracker for these.
The issue tracker is only for bug reports or feature requests.
Documentation
The HAProxy documentation has been split into a number of different files for ease of use. It is available in text format as well as HTML. The wiki is also meant to replace the old architecture guide.
Please refer to the following files depending on what you're looking for:
- INSTALL for instructions on how to build and install HAProxy
- BRANCHES to understand the project's life cycle and what version to use
- LICENSE for the project's license
- CONTRIBUTING for the process to follow to submit contributions
The more detailed documentation is located into the doc/ directory:
- doc/intro.txt for a quick introduction on HAProxy
- doc/configuration.txt for the configuration's reference manual
- doc/lua.txt for the Lua's reference manual
- doc/SPOE.txt for how to use the SPOE engine
- doc/network-namespaces.txt for how to use network namespaces under Linux
- doc/management.txt for the management guide
- doc/regression-testing.txt for how to use the regression testing suite
- doc/peers.txt for the peers protocol reference
- doc/coding-style.txt for how to adopt HAProxy's coding style
- doc/internals for developer-specific documentation (not all up to date)
License
HAProxy is licensed under GPL 2 or any later version, the headers under LGPL 2.1. See the LICENSE file for a more detailed explanation.