Add shopifyGraphQLProxy

package.json

@@ -36,6 +36,7 @@
     "body-parser": "^1.18.2",
     "connect-redis": "^3.3.0",
     "express": "^4.16.2",
+    "express-http-proxy": "^1.2.0",
     "express-session": "^1.15.3",
     "knex": "^0.13.0",
     "node-fetch": "^1.7.3",
@@ -49,7 +50,9 @@
     "husky": "^0.14.3",
     "jest": "^21.2.1",
     "lint-staged": "^5.0.0",
+    "nock": "^9.4.4",
     "prettier": "^1.8.2",
-    "prettier-check": "^2.0.0"
+    "prettier-check": "^2.0.0",
+    "supertest": "^3.1.0"
   }
 }

routes/index.js

@@ -3,6 +3,7 @@ const bodyParser = require('body-parser');
 
 const createShopifyAuthRoutes = require('./shopifyAuth');
 const shopifyApiProxy = require('./shopifyApiProxy');
+const shopifyGraphQLProxy = require('./shopifyGraphQLProxy');
 
 module.exports = function createRouter(shopifyConfig) {
   const router = express.Router();
@@ -17,6 +18,7 @@ module.exports = function createRouter(shopifyConfig) {
     verifyApiCall,
     shopifyApiProxy,
   );
+  router.use(shopifyGraphQLProxy());
 
   return router;
 };

routes/shopifyGraphQLProxy.js

@@ -0,0 +1,34 @@
+const proxy = require('express-http-proxy');
+
+const PROXY_BASE_PATH = '/graphql';
+const GRAPHQL_PATH = '/admin/api/graphql.json';
+
+module.exports = function shopifyGraphQLProxy() {
+  return function shopifyGraphQLProxyMiddleware(req, res, next) {
+    const { session: { shop, accessToken } } = req;
+
+    if (req.path !== PROXY_BASE_PATH || req.method !== 'POST') {
+      return next();
+    }
+
+    if (accessToken == null || shop == null) {
+      return res.status(403).send('Unauthorized');
+    }
+
+    proxy(shop, {
+      https: true,
+      parseReqBody: false,
+      proxyReqOptDecorator(proxyReqOpts, srcReq) {
+        proxyReqOpts.headers['content-type'] = 'application/json';
+        proxyReqOpts.headers['x-shopify-access-token'] = accessToken;
+        return proxyReqOpts;
+      },
+      proxyReqPathResolver(req) {
+        return GRAPHQL_PATH;
+      }
+    })(req, res, next);
+  }
+};
+
+module.exports.PROXY_BASE_PATH = PROXY_BASE_PATH;
+module.exports.GRAPHQL_PATH = GRAPHQL_PATH;

routes/tests/shopifyGraphQLProxy.test.js

@@ -0,0 +1,78 @@
+const request = require('supertest');
+const express = require('express');
+const nock = require('nock');
+const expressShopifyGraphqlProxy = require('../shopifyGraphQLProxy');
+
+describe('shopifyGraphQLProxy', () => {
+  const app = express();
+  app.use(function(req, res, next) { req.session = {}; next(); });
+  app.use(expressShopifyGraphqlProxy());
+
+  it('bails and calls next middleware if request method is not POST', (done) => {
+    request(app)
+      .get('/graphql')
+      .expect(404)
+      .expect(/Cannot GET \/graphql/, done);
+  });
+
+  it('bails and calls next middleware if request path is not /graphql', (done) => {
+    request(app)
+      .post('/not/graphql')
+      .expect(404)
+      .expect(/Cannot POST \/not\/graphql/, done);
+  });
+
+  it('responds 403 unauthorized when no session is provided', (done) => {
+    request(app)
+      .post('/graphql')
+      .expect(403)
+      .expect('Unauthorized', done);
+  });
+
+  it('proxies request to the current logged in shop found in session', (done) => {
+    const app = express();
+
+    app.use(function(req, res, next) {
+      req.session = {
+        shop: 'testshop.myshopify.com',
+        accessToken: 'token'
+      };
+      next();
+    });
+
+    app.use(expressShopifyGraphqlProxy());
+
+    const graphqlAdminAPI = nock('https://testshop.myshopify.com')
+      .post('/admin/api/graphql.json')
+      .reply(200, {
+        data: {
+          shop: {
+            name: 'Test Shop'
+          }
+        },
+        extensions: {
+          cost: {
+            requestedQueryCost: 1,
+            actualQueryCost: 1,
+            throttleStatus: {
+              maximumAvailable: 1000.0,
+              currentlyAvailable:999,
+              restoreRate:50.0
+            }
+          }
+        }
+      }, {
+        'x-shopid': '12345678'
+      });
+
+    request(app)
+      .post('/graphql')
+      .send(JSON.stringify({ query: '{ shop { name } }' }))
+      .end(function(err, res) {
+        expect(res.statusCode).toEqual(200);
+        expect(res.header['x-shopid']).toEqual('12345678');
+        expect(res.body.data.shop.name).toEqual('Test Shop');
+        done();
+      });
+  });
+});