Add Prometheus monitoring integration and enhance application metrics

.devcontainer/devcontainer.json

@@ -16,9 +16,12 @@
   // "postCreateCommand": "bundle install && rake db:setup",
   "postCreateCommand": ".devcontainer/post-create.sh",
   "forwardPorts": [
-    8080, // pgadmin
     3000, // rails development
-    3001 // rails staging
+    3001, // rails staging
+    9394, // prometheus exporter
+    "pgadmin:8080", // pgadmin
+    "grafana:3100", // grafana
+    "prometheus:9090" // prometheus
   ]
   // Configure tool-specific properties.
   // Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root.

.devcontainer/docker-compose.yml

@@ -16,7 +16,6 @@ services:
       OTEL_SERVICE_NAME: redux-scraper-dev
       OTEL_RESOURCE_ATTRIBUTES: application=redux-scraper-dev
     command: sleep infinity
-    network_mode: service:db
 
   db:
     build:
@@ -34,7 +33,6 @@ services:
   pgadmin:
     image: dpage/pgadmin4:8.14.0
     restart: unless-stopped
-    network_mode: service:db
     environment:
       PGADMIN_DEFAULT_EMAIL: admin@example.com
       PGADMIN_DEFAULT_PASSWORD: password
@@ -42,7 +40,28 @@ services:
       PGADMIN_CONFIG_SERVER_MODE: 'False'
       PGADMIN_CONFIG_MASTER_PASSWORD_REQUIRED: 'False'
 
+  prometheus:
+    image: prom/prometheus
+    command:
+      - '--config.file=/etc/prometheus/prometheus.yml'
+    restart: unless-stopped
+    volumes:
+      - ./prometheus:/etc/prometheus
+      - devcontainer-redux-prometheus-data:/prometheus
+
+  grafana:
+    image: grafana/grafana
+    restart: unless-stopped
+    environment:
+      - GF_SERVER_HTTP_PORT=3100
+      - GF_USERS_ALLOW_SIGN_UP=false
+      - GF_LOG_LEVEL=debug
+    volumes:
+      - devcontainer-redux-grafana-data:/var/lib/grafana
+
 volumes:
   postgres-data:
   devcontainer-redux-gem-cache:
   devcontainer-redux-blob-files:
+  devcontainer-redux-grafana-data:
+  devcontainer-redux-prometheus-data:

.devcontainer/post-create.sh

@@ -1,5 +1,12 @@
 #!/bin/bash -ex
 
+function mkdir_and_chmod {
+  sudo mkdir -p $1
+  sudo chmod 777 $1
+}
+
+mkdir_and_chmod .devcontainer/data/prometheus
+mkdir_and_chmod .devcontainer/data/grafana
 echo "Path: $PATH"
 echo "Ruby: $(which ruby)"
 echo "Gem: $(which gem)"

.devcontainer/prometheus/prometheus.yml

@@ -0,0 +1,12 @@
+global:
+  scrape_interval: 15s
+  evaluation_interval: 15s
+
+scrape_configs:
+  - job_name: 'prometheus'
+    static_configs:
+      - targets: ['prometheus:9090']
+
+  - job_name: 'rails'
+    static_configs:
+      - targets: ['app:9394']