Unify layer and tile middlewares

lib/cartodb/controllers/layergroup.js

@@ -48,7 +48,7 @@ LayergroupController.prototype.register = function(app) {
         userMiddleware(),
         this.prepareContext,
         getMapStoreMapConfigProvider(this.mapStore, this.userLimitsApi),
-        getTile(this.tileBackend),
+        getTile(this.tileBackend, 'map_tile'),
         setCacheControlHeader(),
         setLastModifiedHeader(),
         getAffectedTables(this.layergroupAffectedTables, this.pgConnection),
@@ -67,7 +67,7 @@ LayergroupController.prototype.register = function(app) {
         userMiddleware(),
         this.prepareContext,
         getMapStoreMapConfigProvider(this.mapStore, this.userLimitsApi),
-        getTile(this.tileBackend),
+        getTile(this.tileBackend, 'map_tile'),
         setCacheControlHeader(),
         setLastModifiedHeader(),
         getAffectedTables(this.layergroupAffectedTables, this.pgConnection),
@@ -87,7 +87,7 @@ LayergroupController.prototype.register = function(app) {
         userMiddleware(),
         this.prepareContext,
         getMapStoreMapConfigProvider(this.mapStore, this.userLimitsApi),
-        layer(this.tileBackend),
+        getTile(this.tileBackend, 'maplayer_tile'),
         setCacheControlHeader(),
         setLastModifiedHeader(),
         getAffectedTables(this.layergroupAffectedTables, this.pgConnection),
@@ -394,37 +394,9 @@ function parseFormat (format = '') {
     return formatStat;
 }
 
-function getTile (tileBackend) {
-    return function tileMiddleware (req, res, next) {
-        req.profiler.start('windshaft.map_tile');
-
-        const { mapConfigProvider } = res.locals;
-        const params = getRequestParams(res.locals);
-
-        tileBackend.getTile(mapConfigProvider, params, (err, tile, headers, stats = {}) => {
-            req.profiler.add(stats);
-
-            if (err) {
-                return next(err);
-            }
-
-            if (headers) {
-                res.set(headers);
-            }
-
-            const formatStat = parseFormat(req.params.format);
-
-            res.statusCode = getStatusCode(tile, formatStat);
-            res.body = tile;
-
-            next();
-        });
-    };
-}
-
-function layer (tileBackend) {
-    return function layerMiddleware (req, res, next) {
-        req.profiler.start('windshaft.maplayer_tile');
+function getTile (tileBackend, profileLabel = 'tile') {
+    return function getTileMiddleware (req, res, next) {
+        req.profiler.start(`windshaft.${profileLabel}`);
 
         const { mapConfigProvider } = res.locals;
         const params = getRequestParams(res.locals);
@@ -647,7 +619,7 @@ function incrementErrorMetrics (statsClient) {
 
         next(err);
     };
-};
+}
 
 function tileError () {
     return function tileErrorMiddleware (err, req, res, next) {