PLT-7705: API to get data retention policy. (#7539)

* PLT-7705: API to get data retention policy.

* Fix review comments.

api4/api.go

@@ -80,6 +80,8 @@ type Routes struct {
 
 	Elasticsearch *mux.Router // 'api/v4/elasticsearch'
 
+	DataRetention *mux.Router // 'api/v4/data_retention'
+
 	Brand *mux.Router // 'api/v4/brand'
 
 	System *mux.Router // 'api/v4/system'
@@ -185,6 +187,7 @@ func Init(a *app.App, root *mux.Router, full bool) *API {
 	api.BaseRoutes.Reactions = api.BaseRoutes.ApiRoot.PathPrefix("/reactions").Subrouter()
 	api.BaseRoutes.Jobs = api.BaseRoutes.ApiRoot.PathPrefix("/jobs").Subrouter()
 	api.BaseRoutes.Elasticsearch = api.BaseRoutes.ApiRoot.PathPrefix("/elasticsearch").Subrouter()
+	api.BaseRoutes.DataRetention = api.BaseRoutes.ApiRoot.PathPrefix("/data_retention").Subrouter()
 
 	api.BaseRoutes.Emojis = api.BaseRoutes.ApiRoot.PathPrefix("/emoji").Subrouter()
 	api.BaseRoutes.Emoji = api.BaseRoutes.Emojis.PathPrefix("/{emoji_id:[A-Za-z0-9]+}").Subrouter()
@@ -208,6 +211,7 @@ func Init(a *app.App, root *mux.Router, full bool) *API {
 	api.InitCluster()
 	api.InitLdap()
 	api.InitElasticsearch()
+	api.InitDataRetention()
 	api.InitBrand()
 	api.InitJob()
 	api.InitCommand()

api4/data_retention.go

@@ -0,0 +1,30 @@
+// Copyright (c) 2017-present Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+package api4
+
+import (
+	"net/http"
+
+	l4g "github.com/alecthomas/log4go"
+
+	"github.com/mattermost/mattermost-server/utils"
+)
+
+func (api *API) InitDataRetention() {
+	l4g.Debug(utils.T("api.data_retention.init.debug"))
+
+	api.BaseRoutes.DataRetention.Handle("/policy", api.ApiSessionRequired(getPolicy)).Methods("GET")
+}
+
+func getPolicy(c *Context, w http.ResponseWriter, r *http.Request) {
+
+	// No permission check required.
+
+	if policy, err := c.App.GetDataRetentionPolicy(); err != nil {
+		c.Err = err
+		return
+	} else {
+		w.Write([]byte(policy.ToJson()))
+	}
+}

api4/data_retention_test.go

@@ -0,0 +1,16 @@
+// Copyright (c) 2017-present Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+package api4
+
+import (
+	"testing"
+)
+
+func TestDataRetentionGetPolicy(t *testing.T) {
+	th := Setup().InitBasic()
+	defer TearDown()
+
+	_, resp := th.Client.GetDataRetentionPolicy()
+	CheckNotImplementedStatus(t, resp)
+}