Replaced SH_ARGS variables with 'set --' and "${@}" to ensure proper
quoting of haproxy command-line arguments. Then replaced individual
per-config run scripts with a single generic run-test-config.sh that
derives the configuration directory from its own filename. The former
scripts became symlinks, and a new run-empty.sh symlink was added.
Replaced the static key-value attribute storage in update-form instruments
with sample-evaluated attributes, matching the log-record attr change.
The 'attr' keyword now accepts a key and a HAProxy sample expression
evaluated at runtime.
The struct (conf.h) changed from otelc_kv/attr_len to a list of
flt_otel_conf_sample entries. The parser (parser.c) calls
flt_otel_parse_cfg_sample() with n=1 per attr keyword. At runtime
(event.c) each attribute is evaluated via flt_otel_sample_eval() and
added via flt_otel_sample_add_kv() to a bare flt_otel_scope_data_kv,
which is passed to the meter.
Updated documentation, debug macro and test configurations.
Replaced the static key-value attribute storage in log-record with
sample-evaluated attributes. The 'attr' keyword now accepts a key and a
HAProxy sample expression evaluated at runtime, instead of a static string
value.
The struct (conf.h) changed from otelc_kv/attr_len to a list of
flt_otel_conf_sample entries. The parser (parser.c) calls
flt_otel_parse_cfg_sample() with n=1 per attr keyword. At runtime
(event.c) each attribute is evaluated via flt_otel_sample_eval() and added
via flt_otel_sample_add_kv() to a bare flt_otel_scope_data_kv, which is
passed to logger->log_span().
Updated documentation, debug macro and test configurations.
Added "log-record" as the third OpenTelemetry signal alongside traces
(span) and metrics (instrument). This includes the
flt_otel_conf_log_record structure definition, parser keyword defines,
the otel-scope section parser with optional "id", "event", "span", and
"attr" keywords followed by sample fetch expressions or a log-format
string, init/free lifecycle, scope list wiring, log-format evaluation
in flt_otel_scope_run_instrument_record(), a test configuration example,
log-record span reference validation in flt_otel_check(), and logger
handle creation, startup, and teardown in the filter lifecycle.
Added the "instrument" keyword to otel-scope sections for recording metric
measurements alongside traces.
Introduced flt_otel_conf_instrument holding instrument type, description,
unit, sample expressions, and optional key-value attributes. The
supported synchronous integer-precision instrument types were counters,
histograms, up-down counters, and gauges.
Instruments followed a two-form design: a "create" form defined a new
instrument with its type and value expression, while an "update" form
recorded measurements against an existing instrument with per-scope
attributes.
Instrument creation was performed lazily at first use with HA_ATOMIC_CAS
to guarantee thread-safe one-time initialization. The configuration
check phase validated that every update-form had a matching create-form
definition and that create-form names were unique across all scopes.
The meter lifecycle was integrated into filter init and deinit, starting
the meter alongside the tracer and shutting it down during cleanup.
Added span link support, allowing a span to reference other spans or
extracted contexts without establishing a parent relationship.
Introduced the flt_otel_conf_link structure and added a links list to
flt_otel_conf_span. The parser accepted both an inline syntax on the span
declaration line ("span <name> link <target>") and a standalone multi-
argument form ("link <span> ..."), each creating a conf_link entry
appended to the span's link list.
At runtime, each configured link name was resolved against the active
spans and extracted contexts in the runtime context. Resolved references
were collected into flt_otel_scope_data_link entries and passed to the C
wrapper add_link API during span creation.
Initialization, cleanup, and debug dump routines were added for the link
data structures at both configuration and runtime levels.
Added a test suite under addons/otel/test/ for the OpenTelemetry filter.
Five scenarios exercise different filter capabilities: standalone (sa)
covers all hook points including idle-timeout heartbeats, metrics and log
records; compact (cmp) covers the full request/response lifecycle with
ACL-based error handling; context (ctx) tests explicit inject/extract
propagation through numbered context variables; frontend/backend (fe/be)
tests distributed tracing across two HAProxy instances; and empty tests
bare filter initialisation with no active scopes.
A performance benchmarking script (test-speed.sh) uses wrk to measure
throughput and latency at different rate-limit settings (100% through 0%,
disabled, and filter-off). Each scenario includes comprehensive YAML
exporter definitions covering OTLP file/gRPC/HTTP, ostream, memory,
Zipkin, and Elasticsearch backends.
