Merge pull request #421 from Freika/feature/prometheus-monitoring

Prometheus monitoring

.app_version

@@ -1 +1 @@
-0.16.5
+0.16.6

CHANGELOG.md

@@ -5,6 +5,21 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
+# 0.16.6 - 2024-11-20
+
+### Added
+
+- Dawarich now can export metrics to Prometheus. You can find the metrics at `your.host:9394/metrics` endpoint. The metrics are being exported in the Prometheus format and can be scraped by Prometheus server. To enable exporting, set the `PROMETHEUS_EXPORTER_ENABLED` env var in your docker-compose.yml to `true`. Example:
+
+```yaml
+  dawarich_app:
+    image: freikin/dawarich:latest
+    container_name: dawarich_app
+    environment:
+      ...
+      PROMETHEUS_EXPORTER_ENABLED: "true"
+```
+
 # 0.16.5 - 2024-11-18
 
 ### Changed

Gemfile

@@ -18,6 +18,7 @@ gem 'kaminari'
 gem 'lograge'
 gem 'oj'
 gem 'pg'
+gem 'prometheus_exporter'
 gem 'puma'
 gem 'pundit'
 gem 'rails'

Gemfile.lock

@@ -236,6 +236,8 @@ GEM
     patience_diff (1.2.0)
       optimist (~> 3.0)
     pg (1.5.9)
+    prometheus_exporter (2.1.1)
+      webrick
     pry (0.14.2)
       coderay (~> 1.1)
       method_source (~> 1.0)
@@ -413,6 +415,7 @@ GEM
       addressable (>= 2.8.0)
       crack (>= 0.3.2)
       hashdiff (>= 0.4.0, < 2.0.0)
+    webrick (1.9.0)
     websocket-driver (0.7.6)
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.5)
@@ -446,6 +449,7 @@ DEPENDENCIES
   lograge
   oj
   pg
+  prometheus_exporter
   pry-byebug
   pry-rails
   puma

Procfile.prometheus.dev

@@ -0,0 +1,2 @@
+web: bin/rails server -p 3000 -b 0.0.0.0
+prometheus_exporter: bundle exec prometheus_exporter

bin/dev

@@ -6,4 +6,10 @@ then
   gem install foreman
 fi
 
-foreman start -f Procfile.dev
+if [ "$PROMETHEUS_EXPORTER_ENABLED" = "true" ]; then
+  echo "Starting Foreman with Procfile.prometheus.dev..."
+  foreman start -f Procfile.prometheus.dev
+else
+  echo "Starting Foreman with Procfile.dev..."
+  foreman start -f Procfile.dev
+fi

config/initializers/prometheus.rb

@@ -0,0 +1,12 @@
+# in config/initializers/prometheus.rb
+if Rails.env != "test"
+  require 'prometheus_exporter/middleware'
+  require 'prometheus_exporter/instrumentation'
+
+  # This reports stats per request like HTTP status and timings
+  Rails.application.middleware.unshift PrometheusExporter::Middleware
+
+    # this reports basic process stats like RSS and GC info, type master
+  # means it is instrumenting the master process
+  PrometheusExporter::Instrumentation::Process.start(type: "master")
+end

config/initializers/sidekiq.rb

@@ -2,6 +2,11 @@
 
 Sidekiq.configure_server do |config|
   config.redis = { url: ENV['REDIS_URL'] }
+
+  config.server_middleware do |chain|
+    require 'prometheus_exporter/instrumentation'
+    chain.add PrometheusExporter::Instrumentation::Sidekiq
+ end
 end
 
 Sidekiq.configure_client do |config|

config/puma.rb

@@ -41,3 +41,9 @@ pidfile ENV.fetch("PIDFILE") { "tmp/pids/server.pid" }
 
 # Allow puma to be restarted by `bin/rails restart` command.
 plugin :tmp_restart
+
+# Promethues exporter
+after_worker_boot do
+  require 'prometheus_exporter/instrumentation'
+  PrometheusExporter::Instrumentation::Process.start(type:"web")
+end

docker-compose.yml

@@ -65,6 +65,7 @@ services:
       DISTANCE_UNIT: km
       PHOTON_API_HOST: photon.komoot.io
       PHOTON_API_USE_HTTPS: true
+      PROMETHEUS_EXPORTER_ENABLED: false
     logging:
       driver: "json-file"
       options: