Add ExtProc Logging Bits for Immediate Response, Continue and Replace

[melginaldi]

Commit Message: Add stats counter in FilterState for when an immediate response is sent
Additional Description: These bits will be useful for internal debugging. I also did some refactoring of the ext_proc_integration_unit test so testing access logs is less code duplication
Risk Level: Low

Docs Changes: N/A
Release Notes: Add new stats counter for Immediate Response sent
Platform Specific Features: N/A

/assign @yanjunxiang-google

[repokitteh-read-only]

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Please mark your PR as ready when you want it to be reviewed!

🐱

Caused by: #41602 was opened by melginaldi.

see: more, trace.

[melginaldi]

/assign @yanjunxiang-google

[RyanTheOptimist]

/assign @tyxia

[tyxia]

LGTM in general. Thanks for contribution!

I will let @yanjunxiang-google review it as well

[tyxia]

/wait

[adisuissa]

@yanjunxiang-google can you PTAL?

[yanjunxiang-google]

/wait

[tyxia]

Could you elaborate on the motivation and use case ?

continue_and_replace and immediate_response appears to be a niche/specical case, compared to universally applicable fields like call_status, callback_state, and traffic_direction in ext_proc.

Also, if it is for debugging, can we use Envoy trace/log

[tyxia]

/wait

[yanjunxiang-google]

@melginaldi Actually, can we add an Envoy global immediate_response stats and continue_and_replace stats counters here:

envoy/source/extensions/filters/http/ext_proc/ext_proc.h

Line 39 in 6adf830

#define ALL_EXT_PROC_FILTER_STATS(COUNTER) \

. It gives us good idea on these events as well. What's the benefit to put them into a per call stats?

[melginaldi]

@melginaldi Actually, can we add an Envoy global immediate_response stats and continue_and_replace stats counters here:

envoy/source/extensions/filters/http/ext_proc/ext_proc.h

Line 39 in 6adf830

#define ALL_EXT_PROC_FILTER_STATS(COUNTER) \

. It gives us good idea on these events as well. What's the benefit to put them into a per call stats?

Yes, I have changed this PR to have immediate_response as a stats counter instead of a bool. Additionally, I have removed continue and replace as I don't feel it is necessary with #41295

[phlax]

@yanjunxiang-google i think is waiting on further review

[yanjunxiang-google]

LGTM

[phlax]

@tyxia @adisuissa i think this now needs maintainer signoff

[adisuissa]

Thanks, LGTM!
Please also add a release note (in the spirit of

envoy/changelogs/1.8.0.yaml

Lines 83 to 86 in b0f079d

	- area: http
	change: |
	added upstream_rq_completed counter for :ref:`total requests completed
	<config_cluster_manager_cluster_stats_dynamic_http>` to dynamic HTTP counters.

)

[melginaldi]

Thanks, LGTM! Please also add a release note (in the spirit of

envoy/changelogs/1.8.0.yaml

Lines 83 to 86 in b0f079d

	- area: http
	change: |
	added upstream_rq_completed counter for :ref:`total requests completed
	<config_cluster_manager_cluster_stats_dynamic_http>` to dynamic HTTP counters.

)

Done! Thanks for the review

[adisuissa]

LGTM, thanks!