Expose Prometheus metrics via django-prometheus

[matthew-li]

Description

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• Installed and configured django-prometheus to expose Prometheus metrics for Django-related operations at /metrics.
• Updated the Ansible playbook to restrict access to /metrics by IP and user, requiring basic authentication via .htpasswd.
• Added web to ALLOWED_HOSTS in the Docker environment, so that a Prometheus instance within the same Docker network may access metrics via web.

Type of change

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• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

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• Ensure that metrics appear at /metrics.
• Run a local Prometheus instance by extending Docker Compose, and ensure that it scrapes /metrics and is accessible at port 9090:
  • docker-compose.prometheus-extension.yml

    services:
      prometheus:
        image: prom/prometheus:latest
        ports:
          - "9090:9090"
        volumes:
          - ./config/prometheus.yml:/etc/prometheus/prometheus.yml
          - prometheus-data:/prometheus
        command:
          - '--config.file=/etc/prometheus/prometheus.yml'
          - '--storage.tsdb.path=/prometheus'
    
    volumes:
      prometheus-data:
        external: false
    

  • prometheus.yml

    global:
      scrape_interval: 15s
    
    scrape_configs:
      - job_name: 'mybrc'
        static_configs:
          - targets: ['web:80']
    

  • Command: docker compose -p $DOCKER_PROJECT_NAME -f bootstrap/development/docker/docker-compose.yml -f bootstrap/development/docker/docker-compose.prometheus-extension.yml up

PR Self Evaluation

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• My code follows the agreed upon best practices
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (if needed)
• My changes generate no new warnings
• Any dependent changes have been merged and published in the appropriate modules
• I have performed a self-review of my own code