CONTRIB: opentracing: add the OpenTracing filter
This commit adds the OpenTracing filter (hereinafter we will use the
abbreviated name 'the OT filter') to the contrib tree.
The OT filter adds native support for using distributed tracing in HAProxy.
This is enabled by sending an OpenTracing compliant request to one of the
supported tracers; such as Datadog, Jaeger, Lightstep and Zipkin tracers.
Please note: tracers are not listed by any preference, but alphabetically.
The OT filter is a standard HAProxy filter, so what applies to others also
applies to this one (of course, by that I mean what is described in the
documentation, more precisely in the doc/internals/filters.txt file).
The OT filter activation is done explicitly by specifying it in the HAProxy
configuration. If this is not done, the OT filter in no way participates
in the work of HAProxy.
As for the impact on HAProxy speed, this is documented with several tests
located in the test directory, and the result is found in the README-speed-*
files. In short, the speed of operation depends on the way it is used and
the complexity of the configuration, from an almost immeasurable impact to
a significant deceleration (5x and more). I think that in some normal use
the speed of HAProxy with the filter on will be quite satisfactory with a
slowdown of less than 4%.
The OT filter allows intensive use of ACLs, which can be defined anywhere in
the configuration. Thus, it is possible to use the filter only for those
connections that are of interest to us.
More detailed documentation related to the operation, configuration and use
of the filter can be found in the contrib/opentracing directory.
To make the OpenTracing filter easier to configure and compile, several
entries have been added to the Makefile. When running the make utility,
it is possible to use several new arguments:
USE_OT=1 : enable the OpenTracing filter
OT_DEBUG=1 : compile the OpenTracing filter in debug mode
OT_INC=path : force the include path to libopentracing-c-wrapper
OT_LIB=path : force the lib path to libopentracing-c-wrapper
OT_RUNPATH=1 : add libopentracing-c-wrapper RUNPATH to haproxy executable
If USE_OT is set, then an additional Makefile from the contrib/opentracing
directory is included in the compilation process.
diff --git a/contrib/opentracing/include/event.h b/contrib/opentracing/include/event.h
new file mode 100644
index 0000000..8d59163
--- /dev/null
+++ b/contrib/opentracing/include/event.h
@@ -0,0 +1,120 @@
+/***
+ * Copyright 2020 HAProxy Technologies
+ *
+ * This file is part of the HAProxy OpenTracing filter.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+#ifndef _OPENTRACING_EVENT_H_
+#define _OPENTRACING_EVENT_H_
+
+/*
+ * This must be defined in order for macro FLT_OT_EVENT_DEFINES
+ * and structure flt_ot_event_data to have the correct contents.
+ */
+#define AN_REQ_NONE 0
+#define AN_REQ_CLIENT_SESS_START 0
+#define AN_REQ_SERVER_UNAVAILABLE 0
+#define AN_REQ_CLIENT_SESS_END 0
+#define AN_RES_SERVER_SESS_START 0
+#define AN_RES_SERVER_SESS_END 0
+#define SMP_VAL_FE_ 0
+#define SMP_VAL_BE_ 0
+
+/*
+ * Event names are selected to be somewhat compatible with the SPOE filter,
+ * from which the following names are taken:
+ * - on-client-session -> on-client-session-start
+ * - on-frontend-tcp-request
+ * - on-frontend-http-request
+ * - on-backend-tcp-request
+ * - on-backend-http-request
+ * - on-server-session -> on-server-session-start
+ * - on-tcp-response
+ * - on-http-response
+ *
+ * FLT_OT_EVENT_NONE is used as an index for 'ot-scope' sections that do not
+ * have an event defined. The 'ot-scope' sections thus defined can be used
+ * within the 'ot-group' section.
+ *
+ * A description of the macro arguments can be found in the structure
+ * flt_ot_event_data definition
+ */
+#define FLT_OT_EVENT_DEFINES \
+ FLT_OT_EVENT_DEF( NONE, REQ, , , 0, "") \
+ FLT_OT_EVENT_DEF( CLIENT_SESS_START, REQ, CON_ACC, , 1, "on-client-session-start") \
+ FLT_OT_EVENT_DEF( INSPECT_FE, REQ, REQ_CNT, , 1, "on-frontend-tcp-request") \
+ FLT_OT_EVENT_DEF( WAIT_HTTP, REQ, , , 1, "on-http-wait-request") \
+ FLT_OT_EVENT_DEF( HTTP_BODY, REQ, , , 1, "on-http-body-request") \
+ FLT_OT_EVENT_DEF( HTTP_PROCESS_FE, REQ, HRQ_HDR, , 1, "on-frontend-http-request") \
+ FLT_OT_EVENT_DEF( SWITCHING_RULES, REQ, , , 1, "on-switching-rules-request") \
+ FLT_OT_EVENT_DEF( INSPECT_BE, REQ, REQ_CNT, REQ_CNT, 1, "on-backend-tcp-request") \
+ FLT_OT_EVENT_DEF( HTTP_PROCESS_BE, REQ, HRQ_HDR, HRQ_HDR, 1, "on-backend-http-request") \
+/* FLT_OT_EVENT_DEF( HTTP_TARPIT, REQ, , , 1, "on-http-tarpit-request") */ \
+ FLT_OT_EVENT_DEF( SRV_RULES, REQ, , , 1, "on-process-server-rules-request") \
+ FLT_OT_EVENT_DEF( HTTP_INNER, REQ, , , 1, "on-http-process-request") \
+ FLT_OT_EVENT_DEF( PRST_RDP_COOKIE, REQ, , , 1, "on-tcp-rdp-cookie-request") \
+ FLT_OT_EVENT_DEF( STICKING_RULES, REQ, , , 1, "on-process-sticking-rules-request") \
+ FLT_OT_EVENT_DEF( CLIENT_SESS_END, REQ, , , 0, "on-client-session-end") \
+ FLT_OT_EVENT_DEF(SERVER_UNAVAILABLE, REQ, , , 0, "on-server-unavailable") \
+ \
+ FLT_OT_EVENT_DEF( SERVER_SESS_START, RES, , SRV_CON, 0, "on-server-session-start") \
+ FLT_OT_EVENT_DEF( INSPECT, RES, RES_CNT, RES_CNT, 0, "on-tcp-response") \
+ FLT_OT_EVENT_DEF( WAIT_HTTP, RES, , , 1, "on-http-wait-response") \
+ FLT_OT_EVENT_DEF( STORE_RULES, RES, , , 1, "on-process-store-rules-response") \
+ FLT_OT_EVENT_DEF( HTTP_PROCESS_BE, RES, HRS_HDR, HRS_HDR, 1, "on-http-response") \
+ FLT_OT_EVENT_DEF( SERVER_SESS_END, RES, , , 0, "on-server-session-end")
+
+enum FLT_OT_EVENT_enum {
+#define FLT_OT_EVENT_DEF(a,b,c,d,e,f) FLT_OT_EVENT_##b##_##a,
+ FLT_OT_EVENT_DEFINES
+ FLT_OT_EVENT_MAX
+#undef FLT_OT_EVENT_DEF
+};
+
+enum FLT_OT_EVENT_SAMPLE_enum {
+ FLT_OT_EVENT_SAMPLE_TAG = 0,
+ FLT_OT_EVENT_SAMPLE_LOG,
+ FLT_OT_EVENT_SAMPLE_BAGGAGE,
+};
+
+struct flt_ot_event_data {
+ uint an_bit; /* Used channel analyser. */
+ uint smp_opt_dir; /* Fetch direction (request/response). */
+ uint smp_val_fe; /* Valid FE fetch location. */
+ uint smp_val_be; /* Valid BE fetch location. */
+ bool flag_http_inject; /* Span context injection allowed. */
+ const char *name; /* Filter event name. */
+};
+
+struct flt_ot_conf_scope;
+
+
+extern const struct flt_ot_event_data flt_ot_event_data[FLT_OT_EVENT_MAX];
+
+
+int flt_ot_scope_run(struct stream *s, struct filter *f, struct channel *chn, struct flt_ot_conf_scope *conf_scope, const struct timespec *ts, uint dir, char **err);
+int flt_ot_event_run(struct stream *s, struct filter *f, struct channel *chn, int event, char **err);
+
+#endif /* _OPENTRACING_EVENT_H_ */
+
+/*
+ * Local variables:
+ * c-indent-level: 8
+ * c-basic-offset: 8
+ * End:
+ *
+ * vi: noexpandtab shiftwidth=8 tabstop=8
+ */