This patch solves the problem reported in github issue #1204, where the
OpenTracing filter cannot communicate with the selected tracer if HAProxy
is run in daemon mode.
This commit also solves github issue #1274, where the problem manifests
itself when using the 'chroot' keyword in the HAProxy configuration.
This is solved so that the initialization of the OpenTracing plugin is
split into two operations, first the plugin (dynamic library) is loaded
before switching the HAProxy to daemon mode (or chroot) and then the
tracer thread is started.
This means that nothing is retrieved from the file system in runtime.
After applying this commit, opentracing C wrapper version 1.1.0 should be
used because the earlier version does not have separated initialization
functions.
This resolves GitHub issues #1204 and #1274.
This one is the last optional module to build with haproxy, so let's move
it to addons/. It was renamed to "ot" as it was the only one whose USE_*
option did not match the directory name, now this is consistent.
Few changes were required, only the Makefile, and doc were adjusted, as
the directory was already self-contained and relocatable.
Miroslav Zagorac
Willy Tarreau