Update go-marathon

vendor/github.com/gambol99/go-marathon/application_marshalling.go

@@ -0,0 +1,106 @@
+/*
+Copyright 2017 The go-marathon Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package marathon
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+// Alias aliases the Application struct so that it will be marshaled/unmarshaled automatically
+type Alias Application
+
+// TmpEnvSecret holds the secret values deserialized from the environment variables field
+type TmpEnvSecret struct {
+	Secret string `json:"secret,omitempty"`
+}
+
+// TmpSecret holds the deserialized secrets field in a Marathon application configuration
+type TmpSecret struct {
+	Source string `json:"source,omitempty"`
+}
+
+// UnmarshalJSON unmarshals the given Application JSON as expected except for environment variables and secrets.
+// Environment varialbes are stored in the Env field. Secrets, including the environment variable part,
+// are stored in the Secrets field.
+func (app *Application) UnmarshalJSON(b []byte) error {
+	aux := &struct {
+		*Alias
+		Env     map[string]interface{} `json:"env"`
+		Secrets map[string]TmpSecret   `json:"secrets"`
+	}{
+		Alias: (*Alias)(app),
+	}
+	if err := json.Unmarshal(b, aux); err != nil {
+		return fmt.Errorf("malformed application definition %v", err)
+	}
+	env := &map[string]string{}
+	secrets := &map[string]Secret{}
+
+	for envName, genericEnvValue := range aux.Env {
+		switch envValOrSecret := genericEnvValue.(type) {
+		case string:
+			(*env)[envName] = envValOrSecret
+		case map[string]interface{}:
+			for secret, secretStore := range envValOrSecret {
+				if secStore, ok := secretStore.(string); ok && secret == "secret" {
+					(*secrets)[secStore] = Secret{EnvVar: envName}
+					break
+				}
+				return fmt.Errorf("unexpected secret field %v or value type %T", secret, envValOrSecret[secret])
+			}
+		default:
+			return fmt.Errorf("unexpected environment variable type %T", envValOrSecret)
+		}
+	}
+	app.Env = env
+	for k, v := range aux.Secrets {
+		tmp := (*secrets)[k]
+		tmp.Source = v.Source
+		(*secrets)[k] = tmp
+	}
+	app.Secrets = secrets
+	return nil
+}
+
+// MarshalJSON marshals the given Application as expected except for environment variables and secrets,
+// which are marshaled from specialized structs.  The environment variable piece of the secrets and other
+// normal environment variables are combined and marshaled to the env field.  The secrets and the related
+// source are marshaled into the secrets field.
+func (app *Application) MarshalJSON() ([]byte, error) {
+	env := make(map[string]interface{})
+	secrets := make(map[string]TmpSecret)
+
+	if app.Env != nil {
+		for k, v := range *app.Env {
+			env[string(k)] = string(v)
+		}
+	}
+	if app.Secrets != nil {
+		for k, v := range *app.Secrets {
+			env[v.EnvVar] = TmpEnvSecret{Secret: k}
+			secrets[k] = TmpSecret{v.Source}
+		}
+	}
+	aux := &struct {
+		*Alias
+		Env     map[string]interface{} `json:"env,omitempty"`
+		Secrets map[string]TmpSecret   `json:"secrets,omitempty"`
+	}{Alias: (*Alias)(app), Env: env, Secrets: secrets}
+
+	return json.Marshal(aux)
+}