Google AppEngine

You don't have to add each class individually to the black list. They are all regex patterns, so just do this: <extend-configuration-property name="rpc.blacklist" value="com.google.gwt.user.client.ui.*Collection"/> In my case I wanted even finer grained control over which collections get included, so I did this: <extend-configuration-property name="rpc.blacklist" value="-.*List"/> <extend-configuration-property name="rpc.blacklist" value="-.*Map"/> <extend-configuration-property name="rpc.blacklist" value="-.*Collection"/> <extend-configuration-property name="rpc.blacklist" value="+java.util.HashMap"/> <extend-configuration-property name="rpc.blacklist" value="+java.util.LinkedHashMap"/> <extend-configuration-property name="rpc.blacklist" value="+java.util.ArrayList"/>

This tutorial concerns using Google Accounts to maintain the existence of your users in a Google App Engine application. Google App Engine provides the class UserServiceFactory to facilitate that. UserServiceFactory is then used to generate UserService object, which in turn provides the following features createLoginURL createLogoutURL getCurrentUser isUserAdmin isUserLoggedIn You would use UserService object to generate the login URL for the browser. The browser would be directed/redirected to this URL. On reaching this URL, the Google log-in prompt would be displayed by Google's server.

public class DatastoreUploadAction extends AppEngineUploadAction {         @Override         public String executeAction(HttpServletRequest request, List<FileItem> sessionFiles) throws UploadActionException {                 String out = super.executeAction(request, sessionFiles);                 for(FileItem imgItem : sessionFiles) {                         PersistenceManager pm = ContentServiceImpl.getPersistenceManager();                         Transaction tx = pm.currentTransaction();                         try {                             // Start the transaction                             tx.begin();                             InputStream imgStream = imgItem.getInputStream();                                 Blob blob = new Blob(IOUtils.toByteArray(imgStream));                                 ImageBlob imageBlob = new ImageBlob(imgItem.getName(), blob);                             pm.makePersistent(imageBlob);                             // Commit the transaction, flushing the object to the datastore                             tx.commit();                         }                         catch(Exception e) {                                 e.printStackTrace();                         }                         finally {                             if(tx.isActive()) {                                 tx.rollback();                             }                             pm.close();                         }                 }             return out;         } }

to write a string to a twitter account. Here’s my original java code:

You should never store a password in plain text. Use a ir-reversable data hashing algorithm, like sha or md5 Here is how you can create a hash in python: from hashlib import sha256from random import randomrandom_key = random()sha256('%s%s%s'%('YOUR SECRET KEY',random_key,password)) You should also store the random key and hash the user supplied password similarly.

You have three options at the moment, when it comes to a 'multi-tenant' app such as you describe: You can have a single app that your customers add to their domains. Your app will have a single datastore, but you can use the Host header to determine which customer is accessing the app, and segregate the datastore entries based on that. Easy to deploy and upgrade Easy for customers to install Users have to have Google accounts, not Apps accounts, to log in. You can deploy a fresh app instance for each customer. Harder to deploy and upgrade More customer involvement required to install Provides firm separation of data Users can log in with their Apps credentials You can work with Google to create a new Apps Marketplace app All the benefits of point 1 and 2, above Requires Google involvement No certain release date yet

It would need to be something like Transaction txn = dataStore.beginTransaction(); Key key = dataStore.put(txn, question); Entity a1 = new Entity("Answer", key); Entity a2 = new Entity("Answer", key); dataStore.put(txn, a1); dataStore.put(txn, a2); txn.commit();

You create a java project only with the shared files (NOT a GAE project). You DON'T copy any libraries into the lib folder. You should add the required third-party components into your main project. Then you rightclick on the shared project's *source* folder, go to "Build Path -> Remove from build path" item in the context menu. You may, by the way, rename the source folder, so that it has a name different from the default source folder name. Next you rightclick on the main project's folder, go to "Build Path -> Link source".

there are few jars like appengine-testing.jar appengine-local-rutime-shared.jar etc. Basically when you create a new GAE project the eclipse plugin copies some jars automatically in war folder, which are required when you will be running ur application on GAE server, but it doesnt copy few test jars which are required only for local dev env and testing. So what i did i compared jars in my war folder and GAE SDK installed folder. I found that few of jars not included so i included all in my Eclipse build path/Junit run path(but didnt copy into war folder) and that worked for me and then i didnt care to check which were the jars actually needed and which were not as i included all jars. But somehow in docs they have mentioned to included only one or two jars and with these jars junit doesnt work.