Merge pull request #106 from andredigenova/master

Add an option to disable caching of the response headers

Thanks for the clean PR @andredigenova - merging now! 👍

Author: Kevin R. Whitley

README.md

@@ -146,6 +146,7 @@ let cache5min = cache('5 min') // continue to use normally
   enabled:          true|false,     // if false, turns off caching globally (useful on dev)
   redisClient:      client,         // if provided, uses the [node-redis](https://github.com/NodeRedis/node_redis) client instead of [memory-cache](https://github.com/ptarjan/node-cache)
   appendKey:        [],             // if you want the key (which is the URL) to be appended by something in the req object, put req properties here that point to what you want appended. I.E. req.session.id would be ['session', 'id']
+  headerBlacklist:  [],             // list of headers that should never be cached
   statusCodes: {
     exclude:        [],             // list status codes to specifically exclude (e.g. [404, 403] cache all responses unless they had a 404 or 403 status)
     include:        [],             // list status codes to require (e.g. [200] caches ONLY responses with a success/200 code)

src/apicache.js

@@ -37,6 +37,7 @@ function ApiCache() {
     appendKey:          [],
     jsonp:              false,
     redisClient:        false,
+    headerBlacklist:    [],
     statusCodes: {
       include: [],
       exclude: [],
@@ -87,10 +88,19 @@ function ApiCache() {
     index.all.unshift(key)
   }
 
+  function filterBlacklistedHeaders(headers) {
+    return Object.keys(headers).filter(function (key) {
+      return globalOptions.headerBlacklist.indexOf(key) === -1;
+    }).reduce(function (acc, header) {
+        acc[header] = headers[header];
+        return acc;
+    }, {});
+  }
+
   function createCacheObject(status, headers, data, encoding) {
     return {
       status: status,
-      headers: Object.assign({}, headers),
+      headers: filterBlacklistedHeaders(headers),
       data: data,
       encoding: encoding
     }
@@ -184,7 +194,8 @@ function ApiCache() {
 
   function sendCachedResponse(response, cacheObject) {
     var headers = (typeof response.getHeaders === 'function') ? response.getHeaders() : response._headers;
-    Object.assign(headers, cacheObject.headers || {}, {
+
+    Object.assign(headers, filterBlacklistedHeaders(cacheObject.headers || {}), {
       'apicache-store': globalOptions.redisClient ? 'redis' : 'memory',
       'apicache-version': pkg.version
     })

test/api/lib/routes.js

@@ -43,6 +43,14 @@ module.exports = function(app) {
     res.end()
   })
 
+  app.get('/api/testheaderblacklist', function(req, res) {
+    app.requestsProcessed++
+    res.set('x-blacklisted', app.requestsProcessed)
+    res.set('x-notblacklisted', app.requestsProcessed)
+
+    res.json(movies)
+  })
+
   app.get('/api/testcachegroup', function(req, res) {
     app.requestsProcessed++
     req.apicacheGroup = 'cachegroup'

test/apicache_test.js

@@ -160,6 +160,7 @@ describe('.middleware {MIDDLEWARE}', function() {
         appendKey: [ 'test' ],
         jsonp: false,
         redisClient: false,
+        headerBlacklist: [],
         statusCodes: { include: [], exclude: [] },
         events: { expire: undefined },
         headers: {}
@@ -171,6 +172,7 @@ describe('.middleware {MIDDLEWARE}', function() {
         appendKey: [ 'test' ],
         jsonp: false,
         redisClient: false,
+        headerBlacklist: [],
         statusCodes: { include: [], exclude: [] },
         events: { expire: undefined },
         headers: {}
@@ -205,6 +207,7 @@ describe('.middleware {MIDDLEWARE}', function() {
         appendKey: [ 'bar' ],
         jsonp: false,
         redisClient: false,
+        headerBlacklist: [],
         statusCodes: { include: [], exclude: ['400'] },
         events: { expire: undefined },
         headers: {
@@ -218,6 +221,7 @@ describe('.middleware {MIDDLEWARE}', function() {
         appendKey: [ 'foo' ],
         jsonp: false,
         redisClient: false,
+        headerBlacklist: [],
         statusCodes: { include: [], exclude: ['200'] },
         events: { expire: undefined },
         headers: {}
@@ -248,6 +252,7 @@ describe('.middleware {MIDDLEWARE}', function() {
         appendKey: [ 'foo' ],
         jsonp: false,
         redisClient: false,
+        headerBlacklist: [],
         statusCodes: { include: [], exclude: ['400'] },
         events: { expire: undefined },
         headers: {}
@@ -259,6 +264,7 @@ describe('.middleware {MIDDLEWARE}', function() {
         appendKey: [ 'foo' ],
         jsonp: false,
         redisClient: false,
+        headerBlacklist: [],
         statusCodes: { include: [], exclude: ['200'] },
         events: { expire: undefined },
         headers: {}
@@ -298,6 +304,7 @@ describe('.middleware {MIDDLEWARE}', function() {
         appendKey: [ 'foo' ],
         jsonp: false,
         redisClient: false,
+        headerBlacklist: [],
         statusCodes: { include: [], exclude: [] },
         events: { expire: undefined },
         headers: {
@@ -311,6 +318,7 @@ describe('.middleware {MIDDLEWARE}', function() {
         appendKey: [ 'foo' ],
         jsonp: false,
         redisClient: false,
+        headerBlacklist: [],
         statusCodes: { include: [], exclude: [] },
         events: { expire: undefined },
         headers: {}
@@ -362,7 +370,7 @@ describe('.middleware {MIDDLEWARE}', function() {
           })
       })
 
-       it('skips cache when using header "x-apicache-force-fetch (legacy)"', function() {
+      it('skips cache when using header "x-apicache-force-fetch (legacy)"', function() {
         var app = mockAPI.create('10 seconds')
 
         return request(app)
@@ -384,6 +392,25 @@ describe('.middleware {MIDDLEWARE}', function() {
           })
       })
 
+      it('does not cache header in headerBlacklist', function() {
+        var app = mockAPI.create('10 seconds', {headerBlacklist: ['x-blacklisted']})
+
+        return request(app)
+          .get('/api/testheaderblacklist')
+          .expect(200, movies)
+          .then(function(res) {
+            expect(res.headers['x-blacklisted']).to.equal(res.headers['x-notblacklisted'])
+            return request(app)
+              .get('/api/testheaderblacklist')
+              .set('Accept', 'application/json')
+              .expect('Content-Type', /json/)
+              .expect(200, movies)
+              .then(function(res2) {
+                expect(res2.headers['x-blacklisted']).to.not.equal(res2.headers['x-notblacklisted'])
+              })
+          })
+      })
+
       it('properly returns a cached JSON request', function() {
         var app = mockAPI.create('10 seconds')