Add 5-minute HTTP request stats grouped by origin IP

[alowde]

Pull Request Template

Description

Add new metrics for http requests to track performance of different origins (for example; different load balancers fronting the same app servers).

Adds:

• Ratio of 4xx responses to total requests
• Ratio of 5xx responses to total requests
• p50, p95, and p99 quantiles of EdgeTimeToFirstByte

These metrics use the AdaptiveHTTPGroup endpoint to get statistically significant sampled values and return values for a five-minute rolling period to avoid spikes caused by outliers that settle as all samples are aggregated in the Cloudflare metric pipeline.

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Code refactoring
• Other (please describe):

Testing

• I have run make pr-tests and all tests pass
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

Code Quality

• My code follows the style guidelines of this project
• [ x I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation

Before Submitting

Please ensure you have completed the following before submitting your PR:

# Run comprehensive tests
make pr-tests

If the above command fails, please fix the issues before submitting your PR.

Additional Notes

Add any other context about the pull request here.

[exokernel]

@alowde - Code looks good to me. I'm not sure about the graphql issue the Sentry bot is pointing out though. Do you have any insight on that?

[exokernel]

@alowde - Also have you tried running this code in integration to check that there are no issues in a real environment https://launchbay.bigcommerce.net/projects/439/releases/integration

To do that I think you will need to make a change on branch to fpm-cookery recipe here: https://github.com/bigcommerce/fpm-cookery/blob/master/cloudflare-exporter/recipe.rb to get a package on the apt repo in the lower envs

Then update the container repo here https://github.com/bigcommerce/cloudflare-exporter/blob/main/config/install.sh to use that package

And then you can do the deploy to integration linked above.

Yeah this process sucks. We have a ticket to revamp this repo to move deployments to the standard container deployment strategy but so far it hasn't been prioritized. ☹️