Add support to custom log level through command line flag and environment variable

[vitorhugoro1]

• Added on InstrumentationOption the option to define log level.

• Implemented a custom severity enum, called level.go, with options to set log levels based on text using zap.Level as reference.

• Added on CLI the flag -log-level that accept one of LogLevel value, which can be see on level.go ex. otel-go-instrumentation -log-level error, the default value is info.

• Added support to OTEL_LOG_LEVEL which implements LogLevel to set visibility level through environment variable.

• Changed multiples logs level to Debug to improve setup when using in production environment.

• Closes Add log verbosity configuration and move the log in controller.go to debug level #691

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: vitorhugoro1 / name: Vitor Hugo Rodrigues (209f23f, 9f7d2a4, eddaf84, dd9d638, df532a5, 72d3d04, bb3cdba, 8dc0545, 5853576, db79e4c, a0dc6da, 771b1a5, d03c47a, 56871d5, 91e4e34, 70e415f)
• ✅ login: MrAlias / name: Tyler Yahn (55636fc)

[RonFed]

@vitorhugoro1 Do you plan on changing the level of the log line I mentioned in the issue?
In addition, we can use debug level in our tests at

opentelemetry-go-instrumentation/.github/workflows/e2e/k8s/sample-job.yml

Line 29 in e85ddd9

command: ["/otel-go-instrumentation", "-global-impl"]

[pellared]

Shouldn't we support setting via OTEL_LOG_LEVEL env var?

Reference: https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/configuration/sdk-environment-variables.md#general-sdk-configuration

[MrAlias]

Shouldn't we support setting via OTEL_LOG_LEVEL env var?

Reference: https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/configuration/sdk-environment-variables.md#general-sdk-configuration

That is tracked in #691. It is out of scope for this PR.

[pellared]

Shouldn't we support setting via OTEL_LOG_LEVEL env var?
Reference: https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/configuration/sdk-environment-variables.md#general-sdk-configuration

That is tracked in #691. It is out of scope for this PR.

This PR says

Closes #691

[vitorhugoro1]

Shouldn't we support setting via OTEL_LOG_LEVEL env var?
Reference: https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/configuration/sdk-environment-variables.md#general-sdk-configuration

That is tracked in #691. It is out of scope for this PR.

Yeah this PR will implement this change too, I take the approach just with flags because is the way I usually use log levels on container

[vitorhugoro1]

@vitorhugoro1 Do you plan on changing the level of the log line I mentioned in the issue? In addition, we can use debug level in our tests at

opentelemetry-go-instrumentation/.github/workflows/e2e/k8s/sample-job.yml

Line 29 in e85ddd9

command: ["/otel-go-instrumentation", "-global-impl"]

I changed some log level, not just in the line you mentioned but in another which is more suitable to debugging not exactly on a production setup.

Changed the sample job too to use debug level by default

[vitorhugoro1]

Shouldn't we support setting via OTEL_LOG_LEVEL env var?

Reference: https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/configuration/sdk-environment-variables.md#general-sdk-configuration

Added the supporting via environment with the name you suggest

[vitorhugoro1]

@pellared @MrAlias @grcevski it's okay now for you guys?

[grcevski]

LGTM!

[edeNFed]

Can we merge this?
@MrAlias @pellared

[RonFed]

@vitorhugoro1 bump 😄

[vitorhugoro1]

Sorry for the late guys, applied the changes @MrAlias suggested and rebase with the main branch

[RonFed]

@MrAlias can you please have another look?

[vitorhugoro1]

@MrAlias can you review again, please?

[MrAlias]

🚀