refactor: Dry handleAuthData for safer code maintenance in the future

spec/AuthenticationAdaptersV2.spec.js

@@ -487,6 +487,33 @@ describe('Auth Adapter features', () => {
     expect(baseAdapter2.validateAuthData).toHaveBeenCalledTimes(2);
   });
 
+  it('should not perform authData validation twice when data mutated', async () => {
+    spyOn(baseAdapter, 'validateAuthData').and.resolveTo({});
+    await reconfigureServer({
+      auth: { baseAdapter },
+      allowExpiredAuthDataToken: false,
+    });
+
+    const user = new Parse.User();
+
+    await user.save({
+      authData: {
+        baseAdapter: { id: 'baseAdapter', token: "sometoken1" },
+      },
+    });
+
+    expect(baseAdapter.validateAuthData).toHaveBeenCalledTimes(1);
+
+    const user2 = new Parse.User();
+    await user2.save({
+      authData: {
+        baseAdapter: { id: 'baseAdapter', token: "sometoken2" },
+      },
+    });
+
+    expect(baseAdapter.validateAuthData).toHaveBeenCalledTimes(2);
+  });
+
   it('should require additional provider if configured', async () => {
     await reconfigureServer({
       auth: { baseAdapter, additionalAdapter },
@@ -937,7 +964,7 @@ describe('Auth Adapter features', () => {
       allowExpiredAuthDataToken: false,
     });
     logger = require('../lib/logger').logger;
-    spyOn(logger, 'error').and.callFake(() => {});
+    spyOn(logger, 'error').and.callFake(() => { });
     user = new Parse.User();
     await user.save({ authData: { modernAdapter: { id: 'modernAdapter' } } });
     const user2 = new Parse.User();

src/RestWrite.js

@@ -523,10 +523,14 @@ RestWrite.prototype.handleAuthData = async function (authData) {
   const r = await Auth.findUsersWithAuthData(this.config, authData);
   const results = this.filteredObjectsByACL(r);
 
-  if (results.length > 1) {
+  const userId = this.getUserId();
+  const userResult = results[0];
+  const foundUserIsNotCurrentUser = userId && userResult && userId !== userResult.objectId;
+
+  if (results.length > 1 || foundUserIsNotCurrentUser) {
     // To avoid https://github.com/parse-community/parse-server/security/advisories/GHSA-8w3j-g983-8jh5
     // Let's run some validation before throwing
-    await Auth.handleAuthDataValidation(authData, this, results[0]);
+    await Auth.handleAuthDataValidation(authData, this, userResult);
     throw new Parse.Error(Parse.Error.ACCOUNT_ALREADY_LINKED, 'this auth is already used');
   }
 
@@ -544,13 +548,6 @@ RestWrite.prototype.handleAuthData = async function (authData) {
 
   // User found with provided authData
   if (results.length === 1) {
-    const userId = this.getUserId();
-    const userResult = results[0];
-    // Prevent duplicate authData id
-    if (userId && userId !== userResult.objectId) {
-      await Auth.handleAuthDataValidation(authData, this, results[0]);
-      throw new Parse.Error(Parse.Error.ACCOUNT_ALREADY_LINKED, 'this auth is already used');
-    }
 
     this.storage.authProvider = Object.keys(authData).join(',');