Add More Readable Error on Config Load Failures

Author: psavides-aws

test/instance_agent/config_test.rb

@@ -207,5 +207,35 @@ class InstanceAgentConfigTest < InstanceAgentTestCase
         config_file.delete
       end
     end
+
+    should 'raise readable error on config load failure' do
+      config_file = Tempfile.new("config.yml")
+      begin
+        config_file.write <<~FILE
+          this is not valid
+        FILE
+
+        config_file.close
+
+        InstanceAgent::Config.config[:config_file] = config_file.path
+        exception = assert_raise(RuntimeError) { InstanceAgent::Config.load_config }
+
+        message = exception.to_s
+
+        assert_match(/^An error occurred loading the CodeDeploy agent config file at #{config_file.path}. Error message:.*$/, message)
+      ensure
+        config_file.delete
+      end
+    end
+
+    should 'raise readable error on config file not found' do
+      fake_path = "/path/does/not/exist/not_here.yml"
+      InstanceAgent::Config.config[:config_file] = "/path/does/not/exist/not_here.yml"
+      exception = assert_raise(RuntimeError) { InstanceAgent::Config.load_config }
+
+      message = exception.to_s
+
+      assert_match(/^The config file #{fake_path} does not exist or is not readable$/, message)
+    end
   end
 end

vendor/gems/process_manager-0.0.13/lib/process_manager/config.rb

@@ -18,9 +18,13 @@ def self.validate_config
 
     def self.load_config
       if File.readable?(config[:config_file])
-        file_config = YAML.load(File.read(config[:config_file])).symbolize_keys
-        config.update(file_config)
-        config_loaded_callbacks.each{|c| c.call}
+        begin
+          file_config = YAML.load(File.read(config[:config_file])).symbolize_keys
+          config.update(file_config)
+          config_loaded_callbacks.each{|c| c.call}
+        rescue Exception => ex
+          raise "An error occurred loading the CodeDeploy agent config file at #{config[:config_file]}. Error message: #{ex}"
+        end
       else
         raise "The config file #{config[:config_file]} does not exist or is not readable"
       end