Differentiate between failures to load config file not existing vs. parse errors

core/componentConfig.go

@@ -66,16 +66,20 @@ func (cc *ComponentConfig) MergeConfigFile(path string, environment string) (err
 func (cc *ComponentConfig) Load(environment string) (err error) {
 	err = cc.UnmarshalYAMLConfig(environment)
 
-	// fall back to looking for JSON if loading YAML fails.
-	if err != nil {
-		err = cc.UnmarshalJSONConfig(environment)
+	// If success or loading or parsing the file failed for reasons other than it didn't exist, return.
+	if err == nil || !os.IsNotExist(err) {
+		return err
+	}
 
-		if err != nil {
-			// couldn't find any config files, so default back to yaml serialization
-			cc.Serialization = "yaml"
-		}
+	err = cc.UnmarshalJSONConfig(environment)
+
+	// If success or loading or parsing the file failed for reasons other than it didn't exist, return.
+	if err == nil || !os.IsNotExist(err) {
+		return err
 	}
 
+	// Otherwise, no config files were found, so default to yaml serialization and return.
+	cc.Serialization = "yaml"
 	return nil
 }
 

core/componentConfig_test.go

@@ -20,6 +20,24 @@ func TestLoad(t *testing.T) {
 	assert.Equal(t, "myapp", config.Namespace)
 }
 
+func TestFailedYAMLLoad(t *testing.T) {
+	config := ComponentConfig{
+		Path: "../testdata/badyamlconfig",
+	}
+
+	err := config.Load("common")
+	assert.NotNil(t, err)
+}
+
+func TestFailedJSONLoad(t *testing.T) {
+	config := ComponentConfig{
+		Path: "../testdata/badjsonconfig",
+	}
+
+	err := config.Load("common")
+	assert.NotNil(t, err)
+}
+
 func TestMerge(t *testing.T) {
 	currentConfig := NewComponentConfig("../testdata/merge")
 	err := currentConfig.Load("current")

testdata/badjsonconfig/config/common.yaml

@@ -0,0 +1 @@
+THIS IS NOT VALID JSON

testdata/badyamlconfig/config/common.yaml

@@ -0,0 +1,17 @@
+subcomponents:
+  anotherservice:
+    config:
+      image:
+        tag: "744"
+      replicaCount: 1
+  screenprofiler:
+    config:
+      envVar:
+        important: true
+        fabshouldfail: true
+        is_this_a_bug: definitely
+        culprit:"this is where it all goes wrong due to the lack of space between key and value"
+      image:
+        repository: somewheregood.azurecr.io/screenprofiler
+        tag: "73"
+      replicaCount: 1