MemoryLimiter extension as an http/grpc middleware

[shivanthzen]

Description

This PR augments the memorylimiter extension to be an HTTP/GRPC middleware. The extension can be used as an HTTP/GRPC middleware once this is merged.
Example:

receivers:
  otlp:
    protocols:
      grpc:
        middlewares:
          - id: memory_limiter
      http:
        middlewares:
          - id: memory_limiter

extensions:
  memory_limiter:
    check_interval: 1s
    limit_percentage: 1
    spike_limit_percentage: 0.05

..........

Link to tracking issue

Fixes #9591
Fixes #14081

Testing

Setup a minimal collector to test that the middleware is indeed ratelimiting while the memory usage is closer to limit.

receivers:
  otlp:
    protocols:
      grpc:
        middlewares:
          - id: memory_limiter
      http:
        middlewares:
          - id: memory_limiter
processors:
exporters:
  debug:
    verbosity: detailed
    sampling_initial: 5
    sampling_thereafter: 200
    use_internal_logger: false

extensions:
  memory_limiter:
    check_interval: 1s
    limit_percentage: 1 # this is the minimum possible, since it's an integer. 
    spike_limit_percentage: 0.05

service:
  extensions:
    - memory_limiter
  pipelines:
    metrics:
      receivers: [otlp]
      processors: []
      exporters: [debug]
    traces:
      receivers: [otlp]
      processors: []
      exporters: [debug]
    logs:
      receivers: [otlp]
      processors: []
      exporters: [debug]
  telemetry:
    logs:
      level: debug
      development: false
      disable_caller: false
      disable_stacktrace: false

Documentation

Updated the readme for memory limiter extension.

[jmacd]

@shivanthzen Thank you. This looks like a good step forward. Can we add to the memorylimiter extension README.md with an example for use? Would you add a minimal test, at least to be sure that the extension implements the middleware interface? I am not sure what internal support memorylimiter has for testing, but it would be nice to have a small test for the function itself.

[songy23]

Needs make gotidy

[codecov]

Codecov Report

❌ Patch coverage is 0% with 12 lines in your changes missing coverage. Please review.
✅ Project coverage is 92.20%. Comparing base (a9691ee) to head (c6b0b9b).

Files with missing lines	Patch %	Lines
extension/memorylimiterextension/memorylimiter.go	0.00%	12 Missing ⚠️

❌ Your patch check has failed because the patch coverage (0.00%) is below the target coverage (95.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #14071      +/-   ##
==========================================
- Coverage   92.24%   92.20%   -0.04%     
==========================================
  Files         658      658              
  Lines       41168    41180      +12     
==========================================
- Hits        37977    37972       -5     
- Misses       2184     2199      +15     
- Partials     1007     1009       +2     

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[evan-bradley]

Instead of having a test for this, could we use the type checker to assert interface implementation?

You could put the following above line 19 in memorylimiter.go for example:

var _ extensionmiddleware.GRPCServer = (*memoryLimiterExtension)(nil)
var _ extensionmiddleware.HTTPServer = (*memoryLimiterExtension)(nil)