Add a hash of hash response to Heartcheck

CHANGELOG

@@ -1,5 +1,9 @@
 = Heart Check - Changelog
 
+== Version 2.1.0 :: 2021-04-09
+
+ * Add support for response formatters and a single hash formatter
+
 == Version 2.0.0 :: 2020-03-10
 
  * Add support for ruby 2.7

README.md

@@ -101,6 +101,11 @@ Returns general application info and a list of dependencies' URIs, but executes
 
     /monitoring/inspect
 
+## Response formatting
+
+An optional formatter may be set for the monitoring response. We provide the default format
+using a list of hashes and one with a single Hash. Please check `Heartcheck.use_hash_formatter!`
+
 ## Plugins
 
 * [ActiveRecord](https://github.com/locaweb/heartcheck-activerecord)

lib/heartcheck.rb

@@ -6,6 +6,8 @@ module Heartcheck
   require 'heartcheck/errors'
   require 'heartcheck/services'
   require 'heartcheck/logger'
+  require 'heartcheck/formatters/base'
+  require 'heartcheck/formatters/hash_response'
 
   @checks = []
 
@@ -16,6 +18,9 @@ class << self
     # @attr [Heartcheck::Executors::Base] the checks executor backend
     attr_accessor :executor
 
+    # @attr [Heartcheck::Formatters::Base] formats heart check result to something JSON encodedable
+    attr_accessor :formatter
+
     # @attr_writer [Object] change the default logger
     attr_writer :logger
 
@@ -95,6 +100,20 @@ def info_checks
       checks.select { |ctx| ctx.respond_to?(:info) }
     end
 
+    # transforms check results to a response
+    #
+    # @return [Heartcheck::Formatters::Base] or nil
+    def formatter
+      @formatter ||= Heartcheck::Formatters::Base.new
+    end
+
+    # change current formatter to a hash response
+    #
+    # @return [Heartcheck::Formatters::HashResponse]
+    def use_hash_formatter!
+      self.formatter = Heartcheck::Formatters::HashResponse.new
+    end
+
     # an executor class that respond to dispatch(checkers)
     #
     # @return [Heartcheck::Executors::Base]

lib/heartcheck/controllers/base.rb

@@ -13,10 +13,14 @@ def index
       protected
 
       def check(who)
-        MultiJson.dump(executor.dispatch(Heartcheck.send("#{who}_checks")))
+        checks = executor.dispatch(Heartcheck.send("#{who}_checks"))
+        MultiJson.dump(formatter.format(checks))
       end
 
       private
+      def formatter
+        Heartcheck.formatter
+      end
 
       def executor
         Heartcheck.executor

lib/heartcheck/formatters/base.rb

@@ -0,0 +1,9 @@
+module Heartcheck
+  module Formatters
+    class Base
+      def format(checks)
+        checks
+      end
+    end
+  end
+end

lib/heartcheck/formatters/hash_response.rb

@@ -0,0 +1,14 @@
+module Heartcheck
+  module Formatters
+    class HashResponse
+      def format(checks)
+        checks.each_with_object({}) do |check, response|
+          name = check.keys.first
+          result = check.delete(name)
+
+          response[name] = result.merge(check)
+        end
+      end
+    end
+  end
+end

lib/heartcheck/version.rb

@@ -1,3 +1,3 @@
 module Heartcheck
-  VERSION = '2.0.0'.freeze
+  VERSION = '2.1.0'.freeze
 end

spec/lib/heartcheck/formatters/base_spec.rb

@@ -0,0 +1,15 @@
+require 'spec_helper'
+
+describe Heartcheck::Formatters::Base do
+  describe "#format" do
+    let(:check_01) { {dummy1: {status: :ok}, time: 1100} }
+    let(:check_02) { {dummy2: {status: :ok}, time: 100} }
+
+    it "generates a list of with a hashes for every check" do
+      expect(subject.format([check_01, check_02])).to be_eql([
+        {dummy1: {status: :ok}, time: 1100},
+        {dummy2: {status: :ok}, time: 100}
+      ])
+    end
+  end
+end

spec/lib/heartcheck/formatters/hash_response_spec.rb

@@ -0,0 +1,15 @@
+require 'spec_helper'
+
+describe Heartcheck::Formatters::HashResponse do
+  describe "#format" do
+    let(:check_01) { {dummy1: {status: :ok}, time: 1100} }
+    let(:check_02) { {dummy2: {status: :ok}, time: 100} }
+
+    it "generates a single hash with every check as a key" do
+      expect(subject.format([check_01, check_02])).to be_eql({
+        dummy1: {status: :ok, time: 1100},
+        dummy2: {status: :ok, time: 100}
+      })
+    end
+  end
+end

spec/lib/heartcheck_spec.rb

@@ -21,6 +21,27 @@
     end
   end
 
+  describe '#format' do
+    context 'with default' do
+      before(:each) { described_class.instance_variable_set :@formatter, nil }
+      it 'returns a Heartcheck::Formatters::Base' do
+        described_class.setup do |monitor|
+          expect(monitor.formatter).to be_a(Heartcheck::Formatters::Base)
+        end
+      end
+    end
+
+    context 'with hash formatter' do
+      before(:each) { described_class.instance_variable_set :@formatter, nil }
+      it 'returns a Heartcheck::Formatters::Base' do
+        described_class.setup do |monitor|
+          described_class.use_hash_formatter!
+          expect(monitor.formatter).to be_a(Heartcheck::Formatters::HashResponse)
+        end
+      end
+    end
+  end
+
   describe '#executor' do
     context 'with default' do
       it 'returns a Heartcheck::Executors::Base' do