From 055faac14f8482581adf3d6ef58b5e6b2984cc09 Mon Sep 17 00:00:00 2001
From: Eugene Burmakin <iamfrey@gmail.com>
Date: Wed, 20 Nov 2024 12:02:31 +0100
Subject: [PATCH 1/4] Add prometheus_exporter gem and instrumentation to the
 project

---
 Gemfile                           |  1 +
 Gemfile.lock                      |  4 ++++
 config/initializers/prometheus.rb | 15 +++++++++++++++
 config/initializers/sidekiq.rb    |  5 +++++
 config/puma.rb                    |  6 ++++++
 5 files changed, 31 insertions(+)
 create mode 100644 config/initializers/prometheus.rb

diff --git a/Gemfile b/Gemfile
index 45a72399..d831ec9d 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,6 +6,7 @@ git_source(:github) { |repo| "https://github.com/#{repo}.git" }
 ruby File.read('.ruby-version').strip
 
 gem 'bootsnap', require: false
+gem 'prometheus_exporter'
 gem 'chartkick'
 gem 'data_migrate'
 gem 'devise'
diff --git a/Gemfile.lock b/Gemfile.lock
index 091c2c14..551e0ff4 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -233,6 +233,8 @@ 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)
@@ -408,6 +410,7 @@ 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)
@@ -441,6 +444,7 @@ DEPENDENCIES
   lograge
   oj
   pg
+  prometheus_exporter
   pry-byebug
   pry-rails
   puma
diff --git a/config/initializers/prometheus.rb b/config/initializers/prometheus.rb
new file mode 100644
index 00000000..9d25d4ea
--- /dev/null
+++ b/config/initializers/prometheus.rb
@@ -0,0 +1,15 @@
+# in config/initializers/prometheus.rb
+if Rails.env != "test"
+  require 'prometheus_exporter/middleware'
+
+  # This reports stats per request like HTTP status and timings
+  Rails.application.middleware.unshift PrometheusExporter::Middleware
+end
+
+if Rails.env != "test"
+  require 'prometheus_exporter/instrumentation'
+
+  # 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
diff --git a/config/initializers/sidekiq.rb b/config/initializers/sidekiq.rb
index 3d2e4741..d3c9bbea 100644
--- a/config/initializers/sidekiq.rb
+++ b/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|
diff --git a/config/puma.rb b/config/puma.rb
index daaf0369..08673ab4 100644
--- a/config/puma.rb
+++ b/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
+
+# in unicorn/puma/passenger be sure to run a new process instrumenter after fork
+after_worker_boot do
+  require 'prometheus_exporter/instrumentation'
+  PrometheusExporter::Instrumentation::Process.start(type:"web")
+end

From da19196660b2ac1a1f29478f997802ebcc78ad02 Mon Sep 17 00:00:00 2001
From: Eugene Burmakin <iamfrey@gmail.com>
Date: Wed, 20 Nov 2024 13:25:58 +0100
Subject: [PATCH 2/4] Start Prometheus exporter along with the Rails server

---
 .app_version   | 2 +-
 CHANGELOG.md   | 6 ++++++
 Gemfile        | 2 +-
 Procfile.dev   | 1 +
 config/puma.rb | 2 +-
 5 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/.app_version b/.app_version
index 19270385..c3f65805 100644
--- a/.app_version
+++ b/.app_version
@@ -1 +1 @@
-0.16.5
+0.16.6
diff --git a/CHANGELOG.md b/CHANGELOG.md
index e1863d71..47a89c8f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,12 @@ 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 exports metrics to Prometheus. You can find the metrics at `/metrics` endpoint. The metrics are being exported in the Prometheus format and can be scraped by Prometheus server. You can find an example of how to scrape the metrics in the `docker-compose.yml` file in the repository.
+
 # 0.16.5 - 2024-11-18
 
 ### Changed
diff --git a/Gemfile b/Gemfile
index d831ec9d..a1a27f8c 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,7 +6,6 @@ git_source(:github) { |repo| "https://github.com/#{repo}.git" }
 ruby File.read('.ruby-version').strip
 
 gem 'bootsnap', require: false
-gem 'prometheus_exporter'
 gem 'chartkick'
 gem 'data_migrate'
 gem 'devise'
@@ -19,6 +18,7 @@ gem 'kaminari'
 gem 'lograge'
 gem 'oj'
 gem 'pg'
+gem 'prometheus_exporter'
 gem 'puma'
 gem 'pundit'
 gem 'rails'
diff --git a/Procfile.dev b/Procfile.dev
index e6096674..2f1921fb 100644
--- a/Procfile.dev
+++ b/Procfile.dev
@@ -1 +1,2 @@
 web: bin/rails server -p 3000 -b 0.0.0.0
+prometheus_exporter: bundle exec prometheus_exporter
diff --git a/config/puma.rb b/config/puma.rb
index 08673ab4..683d0ba0 100644
--- a/config/puma.rb
+++ b/config/puma.rb
@@ -42,7 +42,7 @@ pidfile ENV.fetch("PIDFILE") { "tmp/pids/server.pid" }
 # Allow puma to be restarted by `bin/rails restart` command.
 plugin :tmp_restart
 
-# in unicorn/puma/passenger be sure to run a new process instrumenter after fork
+# Promethues exporter
 after_worker_boot do
   require 'prometheus_exporter/instrumentation'
   PrometheusExporter::Instrumentation::Process.start(type:"web")

From 6925e5598b28e26530ef7583ed67b07ce7bd5d54 Mon Sep 17 00:00:00 2001
From: Eugene Burmakin <iamfrey@gmail.com>
Date: Wed, 20 Nov 2024 13:56:19 +0100
Subject: [PATCH 3/4] Allow enabling and disabling prometheus exporter in
 docker-compose.yml

---
 CHANGELOG.md            | 11 ++++++++++-
 Procfile.dev            |  1 -
 Procfile.prometheus.dev |  2 ++
 bin/dev                 |  8 +++++++-
 docker-compose.yml      |  1 +
 5 files changed, 20 insertions(+), 3 deletions(-)
 create mode 100644 Procfile.prometheus.dev

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 47a89c8f..8aa52b7a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,7 +9,16 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Added
 
-- Dawarich now exports metrics to Prometheus. You can find the metrics at `/metrics` endpoint. The metrics are being exported in the Prometheus format and can be scraped by Prometheus server. You can find an example of how to scrape the metrics in the `docker-compose.yml` file in the repository.
+- 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
 
diff --git a/Procfile.dev b/Procfile.dev
index 2f1921fb..e6096674 100644
--- a/Procfile.dev
+++ b/Procfile.dev
@@ -1,2 +1 @@
 web: bin/rails server -p 3000 -b 0.0.0.0
-prometheus_exporter: bundle exec prometheus_exporter
diff --git a/Procfile.prometheus.dev b/Procfile.prometheus.dev
new file mode 100644
index 00000000..2f1921fb
--- /dev/null
+++ b/Procfile.prometheus.dev
@@ -0,0 +1,2 @@
+web: bin/rails server -p 3000 -b 0.0.0.0
+prometheus_exporter: bundle exec prometheus_exporter
diff --git a/bin/dev b/bin/dev
index 948d9bc6..8aa6cf2b 100755
--- a/bin/dev
+++ b/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
diff --git a/docker-compose.yml b/docker-compose.yml
index 7324b3b8..bd3d2049 100644
--- a/docker-compose.yml
+++ b/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:

From cf5b414ae46d1b3f324518049cda2c666c63a895 Mon Sep 17 00:00:00 2001
From: Eugene Burmakin <iamfrey@gmail.com>
Date: Wed, 20 Nov 2024 17:16:26 +0100
Subject: [PATCH 4/4] Use single condition in the prometheus initializer file

---
 config/initializers/prometheus.rb | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/config/initializers/prometheus.rb b/config/initializers/prometheus.rb
index 9d25d4ea..a8ffc08d 100644
--- a/config/initializers/prometheus.rb
+++ b/config/initializers/prometheus.rb
@@ -1,15 +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
-end
 
-if Rails.env != "test"
-  require 'prometheus_exporter/instrumentation'
-
-  # this reports basic process stats like RSS and GC info, type master
+    # 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