Enable API related tests for Postgres (#2970)

spec/ParseAPI.spec.js

@@ -1306,7 +1306,7 @@ it('ensure that if you try to sign up a user with a unique username and email, b
     });
   });
 
-  it_exclude_dbs(['postgres'])('bans interior keys containing . or $', done => {
+  it('bans interior keys containing . or $', done => {
     new Parse.Object('Obj').save({innerObj: {'key with a $': 'fails'}})
     .then(() => {
       fail('should not succeed')

src/Adapters/Storage/Postgres/PostgresStorageAdapter.js

@@ -136,6 +136,20 @@ const handleDotFields = (object) => {
   return object;
 }
 
+const validateKeys = (object) => {
+  if (typeof object == 'object') {
+    for (const key in object) {
+      if (typeof object[key] == 'object') {
+        validateKeys(object[key]);
+      }
+
+      if(key.includes('$') || key.includes('.')){
+        throw new Parse.Error(Parse.Error.INVALID_NESTED_KEY, "Nested keys should not contain the '$' or '.' characters");
+      }       
+    }
+  }
+}
+
 // Returns the list of join tables on a schema
 const joinTablesForSchema = (schema) => {
   let list = [];
@@ -649,6 +663,8 @@ export class PostgresStorageAdapter {
 
     object = handleDotFields(object);
 
+    validateKeys(object);
+
     Object.keys(object).forEach(fieldName => {
       var authDataMatch = fieldName.match(/^_auth_data_([a-zA-Z0-9_]+)$/);
       if (authDataMatch) {