chore(devops): set up basic prometheus metrics

[Copilot]

• Install prom-client library
• Create metrics module to initialize and export Prometheus metrics
• Set up default Node.js metrics (CPU, RAM, event loop, etc.)
• Create HTTP middleware to track request duration and count by route, method, and status code
• Create separate Express app for metrics endpoint
• Add METRICS_PORT environment variable to configuration
• Start metrics server on separate port in HawkAPI class
• Test the implementation by checking /metrics endpoint
• Add integration tests for metrics endpoint
• Add documentation for Prometheus metrics integration
• Remove package-lock.json (use yarn instead)
• Fix yarn.lock to preserve git dependency commit hash
• Update Dockerfile.dev and CI workflows to use Node 16

Original prompt

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This section details on the original issue you should resolve

<issue_title>chore(devops): set up basic prometheus metrics</issue_title>
<issue_description>We need to integrate prometheus metrics to the application.

• Must serve prometheus-compatible /metrics endpoint on a different port (not the one API uses to serve user requests)
• Must include default nodejs metrics (for CPU, RAM, etc)
• Must include http-level metrics: count and duration of requests by route, http code and http method
• Use prom-client library</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #539

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[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• fastdl.mongodb.org
  • Triggering command: node ./postinstall.js (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

[neSpecc]

@copilot there is an error during yarn build:

3.908 error An unexpected error occurred: "Commit hash required".

[Copilot]

@copilot there is an error during yarn build:

3.908 error An unexpected error occurred: "Commit hash required".

Fixed. The issue was that yarn.lock had lost the commit hash for the git dependency (codex-accounting-sdk). Restored the original yarn.lock and properly added prom-client using yarn add to preserve the git commit hash. Now yarn install and yarn build work correctly.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• fastdl.mongodb.org
  • Triggering command: /usr/local/bin/node ./postinstall.js (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

[neSpecc]

@copilot some of ci failed: https://github.com/codex-team/hawk.api.nodejs/actions/runs/18358440930/job/52296525978?pr=541

The failing job is caused by using Node.js version 14.17.0, which is incompatible with the prom-client@15.1.3 package. prom-client requires Node.js "^16 || ^18 || >=20".

Consider using node 16 in Dockerfile.dev

And check other CI as well

[Copilot]

@copilot some of ci failed: https://github.com/codex-team/hawk.api.nodejs/actions/runs/18358440930/job/52296525978?pr=541

The failing job is caused by using Node.js version 14.17.0, which is inco...

Updated to Node 16 for prom-client compatibility:

• Dockerfile.dev: Node 14.17.0 → Node 16 (also updated python → python3)
• tests.yml: Added Node.js setup using .nvmrc
• integration-tests.yml: Added Node.js setup using .nvmrc

All CI workflows now use Node 16.16.0 (from .nvmrc), which satisfies prom-client's requirement of "^16 || ^18 || >=20".

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• fastdl.mongodb.org
  • Triggering command: /usr/local/bin/node ./postinstall.js (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)