HeyDoctor - doc c'mon man!

This is a simple stack health check for rails based applications, it mounts a endpoint with the current status of database, application and redis.

Usage

After installing this gem it will mount a endpoint in /_ah/health, this will bring a response like this:

curl localhost:8000/_ah/health

{
   "app":{
      "message":"Application is running",
      "success":true
   },
   "database":{
      "message":"Database is connected",
      "success":true
   },
   "redis":{
      "message":"Redis is connected",
      "success":true
   }
}

Installation

• If you have a redis instance in you application add the following initializer to create a Redis.current, so it don't need to use global vars, or create a new connection each request:

# config/initializers/redis.rb

Redis.current ||= Redis.new(url: ENV['REDIS_URL'])

It is very important to use the env REDIS_URL, because it will be used to check whether or not to render the redis response.

• Add a env var RAILS_PORT with the current application port, it will also work with the env PORT for backward compatibility with GAE applications.

• Add this line to your application's Gemfile:

gem 'hey_doctor'

• And then execute:

bundle install

• After installing the gem, mount the HealthCheck endpoint inside config.ru:

# config.ru

# bunch of requires here
require 'hey_doctor'

map '/_ah/health' do
  run HeyDoctor::Rack::HealthCheck.new
end

...

• The last step is to mount the engine into your application, so if the application is down the middleware will notice:

Rails.application.routes.draw do
  mount HeyDoctor::Engine, at: '/_ah/app_health'

  ...
end

Developing

docker network create dev-net # only the fist time you run this project

docker-compose build && docker-compose up

docker-compose exec web bash

bundle exec rake db:setup

rubocop -A && rspec

Minimum coverage is set to 95%.

Releasing

Change the tag in lib/hey_doctor/version.rb each release using SEMVER.

# After merging the PR checkout to master branch and update it.
git checkout master
git pull

# build gem in pkg/hey_doctor-TAG.gem (Also changes Gemfile.lock)
bundle exec rake build

# Add the changed files
git add Gemfile.lock lib/hey_doctor/version.rb
git commit -m "v0.0.0"

# Create a new git tag
git tag -a v0.0.0 -m "Description here."

bundle exec rake release
# Ask for rubygems credentials and makes the release, push the commit and the tag

Contributing

Fell free to send a PR.

License

The gem is available as open source under the terms of the MIT License.