Fix for #1840, Strip operations from results, forwards delete operations to SDKs (#1946)

* Adding a test demonstrating issue #1840.

* Fixes #1840

* Adds failing test with other use case

- That test fails on parse.com as well

* Bumps parse to 1.9.0

* exclude pg db

* Exclude pg on other test

* Adds clientSDK compatibility check for forward deletion

- Mark js1.9.0 as compatible

* Strips all operations from result

- fix for #1606

src/ClientSDK.js

@@ -0,0 +1,40 @@
+var semver = require('semver');
+
+function compatible(compatibleSDK) {
+  return function(clientSDK) {
+    if (typeof clientSDK === 'string') {
+      clientSDK = fromString(clientSDK);
+    }
+    // REST API, or custom SDK
+    if (!clientSDK) {
+      return true;
+    }
+    let clientVersion = clientSDK.version;
+    let compatiblityVersion = compatibleSDK[clientSDK.sdk];
+    return semver.satisfies(clientVersion, compatiblityVersion);
+  }
+}
+
+function supportsForwardDelete(clientSDK) {
+  return compatible({
+    js: '>=1.9.0'
+  })(clientSDK);
+}
+
+function fromString(version) {
+  let versionRE = /([-a-zA-Z]+)([0-9\.]+)/;
+  let match = version.toLowerCase().match(versionRE);
+  if (match && match.length === 3) {
+    return {
+      sdk: match[1],
+      version: match[2]
+    }
+  }
+  return undefined;
+}
+
+module.exports = {
+  compatible,
+  supportsForwardDelete,
+  fromString
+}

src/RestWrite.js

@@ -11,6 +11,7 @@ var cryptoUtils = require('./cryptoUtils');
 var passwordCrypto = require('./password');
 var Parse = require('parse/node');
 var triggers = require('./triggers');
+var ClientSDK = require('./ClientSDK');
 import RestQuery from './RestQuery';
 import _         from 'lodash';
 
@@ -774,9 +775,7 @@ RestWrite.prototype.runDatabaseOperation = function() {
     .then(response => {
       response.updatedAt = this.updatedAt;
       if (this.storage.changedByTrigger) {
-        Object.keys(this.data).forEach(fieldName => {
-          response[fieldName] = response[fieldName] || this.data[fieldName];
-        });
+        this.updateResponseWithData(response, this.data);
       }
       this.response = { response };
     });
@@ -834,9 +833,7 @@ RestWrite.prototype.runDatabaseOperation = function() {
         response.username = this.data.username;
       }
       if (this.storage.changedByTrigger) {
-        Object.keys(this.data).forEach(fieldName => {
-          response[fieldName] = response[fieldName] || this.data[fieldName];
-        });
+        this.updateResponseWithData(response, this.data);
       }
       this.response = {
         status: 201,
@@ -925,5 +922,24 @@ RestWrite.prototype.cleanUserAuthData = function() {
   }
 };
 
+RestWrite.prototype.updateResponseWithData = function(response, data) {
+  let clientSupportsDelete = ClientSDK.supportsForwardDelete(this.clientSDK);
+  Object.keys(data).forEach(fieldName => {
+    let dataValue = data[fieldName];
+    let responseValue = response[fieldName];
+
+    response[fieldName] = responseValue || dataValue;
+    
+    // Strips operations from responses
+    if (response[fieldName] && response[fieldName].__op) {
+      delete response[fieldName];
+      if (clientSupportsDelete && dataValue.__op == 'Delete') {
+        response[fieldName] = dataValue;
+      }
+    }
+  });
+  return response;
+}
+
 export default RestWrite;
 module.exports = RestWrite;

src/middlewares.js

@@ -5,17 +5,7 @@ var Parse = require('parse/node').Parse;
 
 var auth = require('./Auth');
 var Config = require('./Config');
-
-function clientSDKFromVersion(version) {
-  let versionRE = /([-a-zA-Z]+)([0-9\.]+)/;
-  let match = version.toLowerCase().match(versionRE);
-  if (match && match.length === 3) {
-    return {
-      sdk: match[1],
-      version: match[2]
-    }
-  }
-}
+var ClientSDK = require('./ClientSDK');
 
 // Checks that the request is authorized for this app and checks user
 // auth too.
@@ -106,7 +96,7 @@ function handleParseHeaders(req, res, next) {
   }
 
   if (info.clientVersion) {
-    info.clientSDK = clientSDKFromVersion(info.clientVersion);
+    info.clientSDK = ClientSDK.fromString(info.clientVersion);
   }
 
   if (fileViaJSON) {
@@ -300,5 +290,4 @@ module.exports = {
   handleParseHeaders: handleParseHeaders,
   enforceMasterKeyAccess: enforceMasterKeyAccess,
   promiseEnforceMasterKeyAccess,
-  clientSDKFromVersion
 };