Extract last-modified header middlleware

lib/cartodb/controllers/layergroup.js

@@ -11,6 +11,7 @@ const rateLimit = require('../middleware/rate-limit');
 const { RATE_LIMIT_ENDPOINTS_GROUPS } = rateLimit;
 const cacheChannelHeader = require('../middleware/cache-channel-header');
 const surrogateKeyHeader = require('../middleware/surrogate-key-header');
+const lastModifiedHeader = require('../middleware/last-modified-header');
 const sendResponse = require('../middleware/send-response');
 const DataviewBackend = require('../backends/dataview');
 const AnalysisStatusBackend = require('../backends/analysis-status');
@@ -87,9 +88,9 @@ LayergroupController.prototype.register = function(app) {
         ),
         getTile(this.tileBackend, 'map_tile'),
         setCacheControlHeader(),
-        setLastModifiedHeader(),
         cacheChannelHeader(),
         surrogateKeyHeader({ surrogateKeysCache: this.surrogateKeysCache }),
+        lastModifiedHeader(),
         incrementSuccessMetrics(global.statsClient),
         sendResponse(),
         incrementErrorMetrics(global.statsClient),
@@ -116,9 +117,9 @@ LayergroupController.prototype.register = function(app) {
         ),
         getTile(this.tileBackend, 'map_tile'),
         setCacheControlHeader(),
-        setLastModifiedHeader(),
         cacheChannelHeader(),
         surrogateKeyHeader({ surrogateKeysCache: this.surrogateKeysCache }),
+        lastModifiedHeader(),
         incrementSuccessMetrics(global.statsClient),
         sendResponse(),
         incrementErrorMetrics(global.statsClient),
@@ -146,9 +147,9 @@ LayergroupController.prototype.register = function(app) {
         ),
         getTile(this.tileBackend, 'maplayer_tile'),
         setCacheControlHeader(),
-        setLastModifiedHeader(),
         cacheChannelHeader(),
         surrogateKeyHeader({ surrogateKeysCache: this.surrogateKeysCache }),
+        lastModifiedHeader(),
         incrementSuccessMetrics(global.statsClient),
         sendResponse(),
         incrementErrorMetrics(global.statsClient),
@@ -175,9 +176,9 @@ LayergroupController.prototype.register = function(app) {
         ),
         getFeatureAttributes(this.attributesBackend),
         setCacheControlHeader(),
-        setLastModifiedHeader(),
         cacheChannelHeader(),
         surrogateKeyHeader({ surrogateKeysCache: this.surrogateKeysCache }),
+        lastModifiedHeader(),
         sendResponse()
     );
 
@@ -203,9 +204,9 @@ LayergroupController.prototype.register = function(app) {
         ),
         getPreviewImageByCenter(this.previewBackend),
         setCacheControlHeader(),
-        setLastModifiedHeader(),
         cacheChannelHeader(),
         surrogateKeyHeader({ surrogateKeysCache: this.surrogateKeysCache }),
+        lastModifiedHeader(),
         sendResponse()
     );
 
@@ -229,9 +230,9 @@ LayergroupController.prototype.register = function(app) {
         ),
         getPreviewImageByBoundingBox(this.previewBackend),
         setCacheControlHeader(),
-        setLastModifiedHeader(),
         cacheChannelHeader(),
         surrogateKeyHeader({ surrogateKeysCache: this.surrogateKeysCache }),
+        lastModifiedHeader(),
         sendResponse()
     );
 
@@ -272,9 +273,9 @@ LayergroupController.prototype.register = function(app) {
         ),
         getDataview(this.dataviewBackend),
         setCacheControlHeader(),
-        setLastModifiedHeader(),
         cacheChannelHeader(),
         surrogateKeyHeader({ surrogateKeysCache: this.surrogateKeysCache }),
+        lastModifiedHeader(),
         sendResponse()
     );
 
@@ -297,9 +298,9 @@ LayergroupController.prototype.register = function(app) {
         ),
         getDataview(this.dataviewBackend),
         setCacheControlHeader(),
-        setLastModifiedHeader(),
         cacheChannelHeader(),
         surrogateKeyHeader({ surrogateKeysCache: this.surrogateKeysCache }),
+        lastModifiedHeader(),
         sendResponse()
     );
 
@@ -322,9 +323,9 @@ LayergroupController.prototype.register = function(app) {
         ),
         dataviewSearch(this.dataviewBackend),
         setCacheControlHeader(),
-        setLastModifiedHeader(),
         cacheChannelHeader(),
         surrogateKeyHeader({ surrogateKeysCache: this.surrogateKeysCache }),
+        lastModifiedHeader(),
         sendResponse()
     );
 
@@ -347,9 +348,9 @@ LayergroupController.prototype.register = function(app) {
         ),
         dataviewSearch(this.dataviewBackend),
         setCacheControlHeader(),
-        setLastModifiedHeader(),
         cacheChannelHeader(),
         surrogateKeyHeader({ surrogateKeysCache: this.surrogateKeysCache }),
+        lastModifiedHeader(),
         sendResponse()
     );
 
@@ -609,20 +610,6 @@ function getPreviewImageByBoundingBox (previewBackend) {
     };
 }
 
-function setLastModifiedHeader () {
-    return function setLastModifiedHeaderMiddleware (req, res, next) {
-        let { cache_buster: cacheBuster } = res.locals;
-
-        cacheBuster = parseInt(cacheBuster, 10);
-
-        const lastUpdated = res.locals.cache_buster ? new Date(cacheBuster) : new Date();
-
-        res.set('Last-Modified', lastUpdated.toUTCString());
-
-        next();
-    };
-}
-
 function setCacheControlHeader () {
     return function setCacheControlHeaderMiddleware (req, res, next) {
         res.set('Cache-Control', 'public,max-age=31536000');

lib/cartodb/controllers/map.js

@@ -13,6 +13,7 @@ const dbConnSetup = require('../middleware/db-conn-setup');
 const authorize = require('../middleware/authorize');
 const cacheChannelHeader = require('../middleware/cache-channel-header');
 const surrogateKeyHeader = require('../middleware/surrogate-key-header');
+const lastModifiedHeader = require('../middleware/last-modified-header');
 const sendResponse = require('../middleware/send-response');
 const NamedMapMapConfigProvider = require('../models/mapconfig/provider/named-map-provider');
 const CreateLayergroupMapConfigProvider = require('../models/mapconfig/provider/create-layergroup-provider');
@@ -115,7 +116,7 @@ MapController.prototype.composeCreateMapMiddleware = function (endpointGroup, us
         augmentLayergroupData(),
         cacheChannelHeader(),
         surrogateKeyHeader({ surrogateKeysCache: this.surrogateKeysCache }),
-        setLastModified(),
+        lastModifiedHeader({ now: true }),
         setLastUpdatedTimeToLayergroup(),
         setCacheControl(),
         setLayerStats(this.pgConnection, this.statsBackend),
@@ -400,16 +401,6 @@ function augmentLayergroupData () {
     };
 }
 
-function setLastModified () {
-    return function setLastModifiedMiddleware (req, res, next) {
-        if (req.method === 'GET') {
-            res.set('Last-Modified', (new Date()).toUTCString());
-        }
-
-        next();
-    };
-}
-
 function setLastUpdatedTimeToLayergroup () {
     return function setLastUpdatedTimeToLayergroupMiddleware (req, res, next) {
         const { mapConfigProvider, analysesResults } = res.locals;

lib/cartodb/middleware/last-modified-header.js

@@ -1,4 +1,4 @@
-module.exports = function setLastModifiedHeader () {
+module.exports = function setLastModifiedHeader ({ now = false } = {}) {
     return function setLastModifiedHeaderMiddleware(req, res, next) {
         if (req.method !== 'GET') {
             return next();
@@ -8,10 +8,16 @@ module.exports = function setLastModifiedHeader () {
 
         if (cache_buster) {
             const cacheBuster = parseInt(cache_buster, 10);
+            const lastModifiedDate = Number.isFinite(cacheBuster) ? new Date(cacheBuster) : new Date();
 
-            if (Number.isFinite(cacheBuster)) {
-                res.set('Last-Modified',  new Date(cacheBuster).toUTCString());
-            }
+            res.set('Last-Modified', lastModifiedDate.toUTCString());
+
+            return next();
+        }
+
+        // REVIEW: to keep 100% compatibility with maps controller
+        if (now) {
+            res.set('Last-Modified', new Date().toUTCString());
 
             return next();
         }
@@ -23,14 +29,13 @@ module.exports = function setLastModifiedHeader () {
             }
 
             if (!affectedTables) {
+                res.set('Last-Modified', new Date().toUTCString());
+
                 return next();
             }
 
             const lastUpdatedAt = affectedTables.getLastUpdatedAt();
-
-            const lastModifiedDate = Number.isFinite(lastUpdatedAt) ?
-                new Date(lastUpdatedAt) :
-                new Date();
+            const lastModifiedDate = Number.isFinite(lastUpdatedAt) ? new Date(lastUpdatedAt) : new Date();
 
             res.set('Last-Modified', lastModifiedDate.toUTCString());