@soulbird Shall we also update the corresponding test cases?

@soulbird Shall we also update the corresponding test cases?
Looks like no corresponding test cases need to be updated.

ref: open-telemetry/opentelemetry-specification#1970

@soulbird Shall we also update the corresponding test cases?
Looks like no corresponding test cases need to be updated.

Why？ No test cases for opentelemetry？

the title of this PR should add opentelemetry

@soulbird Shall we also update the corresponding test cases?
Looks like no corresponding test cases need to be updated.

Why？ No test cases for opentelemetry？

In the test cases of opentelemetry, the data is reported to the black hole, and there is no port-related test. Look: https://github.com/apache/apisix/blob/master/t/plugin/opentelemetry.t#L41

@soulbird Shall we also update the corresponding test cases?
Looks like no corresponding test cases need to be updated.

Why？ No test cases for opentelemetry？

In the test cases of opentelemetry, the data is reported to the black hole, and there is no port-related test. Look: https://github.com/apache/apisix/blob/master/t/plugin/opentelemetry.t#L41

Is opentelemetry really started? If yes, there should be has port

@soulbird Shall we also update the corresponding test cases?
Looks like no corresponding test cases need to be updated.

Why？ No test cases for opentelemetry？

In the test cases of opentelemetry, the data is reported to the black hole, and there is no port-related test. Look: https://github.com/apache/apisix/blob/master/t/plugin/opentelemetry.t#L41

Is opentelemetry really started? If yes, there should be has port

No services related to opentelemetry were found to be started.

This port change problem should be covered with test cases

This port change problem should be covered with test cases

I think it is not necessary to add test coverage related to the default port, and the success or failure of the report will not affect the operation of APISIX. You can see that the do_request function does not return any relevant error information, it just output a log. Look: https://github.com/yangxikun/opentelemetry-lua/blob/main/lib/opentelemetry/trace/exporter/http_client.lua#L30
cc @spacewander

So should this function return an error message?

This port change problem should be covered with test cases

I think it is not necessary to add test coverage related to the default port, and the success or failure of the report will not affect the operation of APISIX. You can see that the do_request function does not return any relevant error information, it just output a log. Look: https://github.com/yangxikun/opentelemetry-lua/blob/main/lib/opentelemetry/trace/exporter/http_client.lua#L30 cc @spacewander

In the test, the do_request is replaced to a stub:

So changing the port won't affect the behavior of the test, and the correctness of trace reporting is covered by lua-opentelemetry itself.

On the other hand, as the default network port for OTLP/HTTP is changed from 4317 to 4318 in open-telemetry/opentelemetry-specification#1970, it is necessary to change APISIX to adapt to the new break change.

CC the author of lua-opentelemetry and this plugin: @yangxikun

Maybe its my careless to use 4317 port as default value. Change 4317 to 4318 is fine. Users usually configure the plugin option collector.address explicitly instead of using the default values.
I think test case is not need for this case.