in_opentelemetry: attempt to fix tag_from_uri

[shaohme]

Pass on tag with length so that tag_from_uri get applied on OpenTelemetry input plugin

Fixes #8734

Enter [N/A] in the box, if an item is not applicable to your change.

Testing
Before we can approve your change; please submit the following in a comment:

• Example configuration file for the change

service:
  flush: 1
  log_file: /tmp/fluent-bit.log
  daemon: false
  log_level: debug
pipeline:
  inputs:
    - name: opentelemetry
      listen: 127.0.0.1
      port: 9999
      raw_traces: false
      successful_response_code: 200
      tag_from_uri: true
      http2: false
  outputs:
    - name: stdout
      match: "v1_traces"

• Debug log output from testing the change

[2024/05/27 14:58:22] [ info] [fluent bit] version=3.0.7, commit=dffcd42ada, pid=1820178
[2024/05/27 14:58:22] [debug] [engine] coroutine stack size: 24576 bytes (24.0K)
[2024/05/27 14:58:22] [ info] [storage] ver=1.5.2, type=memory, sync=normal, checksum=off, max_chunks_up=128
[2024/05/27 14:58:22] [ info] [cmetrics] version=0.9.0
[2024/05/27 14:58:22] [ info] [ctraces ] version=0.5.1
[2024/05/27 14:58:22] [ info] [input:opentelemetry:opentelemetry.0] initializing
[2024/05/27 14:58:22] [ info] [input:opentelemetry:opentelemetry.0] storage_strategy='memory' (memory only)
[2024/05/27 14:58:22] [debug] [opentelemetry:opentelemetry.0] created event channels: read=22 write=18
[2024/05/27 14:58:22] [debug] [downstream] listening on 127.0.0.1:9999
[2024/05/27 14:58:22] [ info] [input:opentelemetry:opentelemetry.0] listening on 127.0.0.1:9999
[2024/05/27 14:58:22] [debug] [stdout:stdout.0] created event channels: read=24 write=25
[2024/05/27 14:58:22] [ info] [sp] stream processor started
[2024/05/27 14:58:22] [ info] [output:stdout:stdout.0] worker #0 started
[2024/05/27 14:58:24] [debug] [task] created task=0x7f2811436640 id=0 OK
[2024/05/27 14:58:24] [debug] [output:stdout:stdout.0] task_id=0 assigned to thread #0
[2024/05/27 14:58:24] [debug] [output:stdout:stdout.0] ctr decode msgpack returned : 6
[2024/05/27 14:58:24] [debug] [out flush] cb_destroy coro_id=0
[2024/05/27 14:58:24] [debug] [task] destroy task=0x7f2811436640 (task_id=0)
[2024/05/27 14:58:25] [debug] [task] created task=0x7f28114366e0 id=0 without routes, dropping.
[2024/05/27 14:58:25] [debug] [task] destroy task=0x7f28114366e0 (task_id=0)
[2024/05/27 14:58:25] [debug] [task] created task=0x7f28114366e0 id=0 OK
[2024/05/27 14:58:25] [debug] [output:stdout:stdout.0] task_id=0 assigned to thread #0
[2024/05/27 14:58:25] [debug] [output:stdout:stdout.0] ctr decode msgpack returned : 6
[2024/05/27 14:58:25] [debug] [out flush] cb_destroy coro_id=1
[2024/05/27 14:58:25] [debug] [task] destroy task=0x7f28114366e0 (task_id=0)
[2024/05/27 14:58:26] [debug] [task] created task=0x7f28114365a0 id=0 without routes, dropping.
[2024/05/27 14:58:26] [debug] [task] destroy task=0x7f28114365a0 (task_id=0)
[2024/05/27 14:58:26] [debug] [task] created task=0x7f28114365a0 id=0 OK
[2024/05/27 14:58:26] [debug] [output:stdout:stdout.0] task_id=0 assigned to thread #0
[2024/05/27 14:58:26] [debug] [output:stdout:stdout.0] ctr decode msgpack returned : 6
[2024/05/27 14:58:26] [debug] [out flush] cb_destroy coro_id=2
[2024/05/27 14:58:26] [debug] [task] destroy task=0x7f28114365a0 (task_id=0)
[2024/05/27 14:58:28] [ warn] [engine] service will shutdown in max 5 seconds
[2024/05/27 14:58:28] [ info] [engine] service has stopped (0 pending tasks)
[2024/05/27 14:58:28] [ info] [output:stdout:stdout.0] thread worker #0 stopping...
[2024/05/27 14:58:28] [ info] [output:stdout:stdout.0] thread worker #0 stopped

• [N/A] Attached Valgrind output that shows no leaks or memory corruption was found

If this is a change to packaging of containers or native binaries then please confirm it works for all targets.

• Run local packaging test showing all targets (including any new ones) build.
• Set ok-package-test label to test for all targets (requires maintainer to do).

Documentation

• [N/A] Documentation required for this feature

Backporting

• Backport to latest stable release.

---

Fluent Bit is licensed under Apache 2.0, by submitting this pull request I understand that this code will be released under the terms of that license.

[nuclearpidgeon]

I'm at a loss as to why this was never implemented in the first place... perhaps at some point there was an issue with tag-based routing at the point this code was written ¯_(ツ)_/¯. Nice work fixing it up! This was what I was hoping to PR at some point myself.

[cosmo0920]

Hi, fluent organization requires to add DCO. So, could you add Signed-off in your commit?
The description is here: https://github.com/fluent/fluent-bit/pull/8881/checks?check_run_id=25458914982

[shaohme]

Hi, fluent organization requires to add DCO. So, could you add Signed-off in your commit? The description is here: https://github.com/fluent/fluent-bit/pull/8881/checks?check_run_id=25458914982

Sure. Should be added now. Had to force push.

[cosmo0920]

Plus, we need to add prefix for changed module name into commit message(s).
In this case, we need to use "in_opentelemery: attempt to fix tag_from_uri" in your commit message.

see also: https://github.com/fluent/fluent-bit/blob/master/CONTRIBUTING.md#commit-changes

[shaohme]

Plus, we need to add prefix for changed module name into commit message(s). In this case, we need to use "in_opentelemery: attempt to fix tag_from_uri" in your commit message.

see also: https://github.com/fluent/fluent-bit/blob/master/CONTRIBUTING.md#commit-changes

Should be fixed now. And I should probably have read a contributors manual first ... 😏

[cosmo0920]

Declaring middle of the function is not good coding style on Fluent Bit.
Could you declare a variable in the beginning of this function? And then, calculate length of tag here should be fine.

[shaohme]

Declaring middle of the function is not good coding style on Fluent Bit. Could you declare a variable in the beginning of this function? And then, calculate length of tag here should be fine.

Sure can. Should be pushed now.

[cosmo0920]

Looks fine to me.