Print OpenTelemetry Configuration

[joe-elliott]

Which problem is this PR solving?

• Fixes Print final configuration #2253

Short description of the changes

• Consolidation of config factory
• Addition of config.dump-otel flag
• Moved zipkin host port configuration into the zipkinreceiver CreateDefaultConfig(). This mimics the way the jaegerreceiver works and removes the ZipkinHostPort field from ComponentSettings.

Notes

• fmt.Println is crude but was chosen b/c it would be unaffected by config like a logger and cleanly dumps the config to stdout.
• I am purposefully exiting after printing the config to protect secrets. Otherwise it might be easy to leave this parameter in and deploy it to production and accidentally dump secrets.

Todo

• Tests

@pavolloffay If you have a chance to review this and make sure I'm headed the right direction please do. I intend to add tests and drop draft status if this change is what is desired.

[joe-elliott]

@pavolloffay I think this PR is in a good spot. Added a basic test to make sure that config factory returned an error if the dump otel flag was passed. Let me know what you think.

[jpkrohling]

crossdoc-otel job restarted.

[codecov]

Codecov Report

Merging #2475 into master will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #2475      +/-   ##
==========================================
+ Coverage   95.51%   95.53%   +0.01%     
==========================================
  Files         208      208              
  Lines       10750    10750              
==========================================
+ Hits        10268    10270       +2     
+ Misses        406      405       -1     
+ Partials       76       75       -1     

Impacted Files	Coverage Δ
plugin/storage/badger/spanstore/reader.go	96.79% <0.00%> (+0.64%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update df2582d...fd89df4. Read the comment docs.

[pavolloffay]

The upstream collector does not have a default config in terms of enabled components, however each component creates a component config with default settings that are unknown to the user.

So I think this feature might be also useful in the upstream OTel collector. There might be more ways how to approach this either add a flag that prints the full config or print the component config when a component is being started. I have filed an issue in OTEL open-telemetry/opentelemetry-collector#1791

[joe-elliott]

Sounds good, we can leave this for a bit and then close it if otel collector is ok with adding this functionality.

Oh, what did you think about moving the ZipkinHostPort field? I think that is a good improvement regardless.

[joe-elliott]

Going to close this PR in favor of doing this upstream as linked by @pavolloffay. The refactoring in this PR was taken care of in #2495