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Google app engine uses the concept of static files. This is a performance optimization. Using the file appengine-web.xml you can configure the way google handles static files. You can include and exclude certain files using their extension or name. More information can be found here at google. This all works nice in the online version, however there seems to be a problem with the development server. Some solutions try to configure the local version as well, still that did not work for me. I decided to look for a servlet that serves static files.

That is it, now you can test your stuff locally and all your scripts, images, styles are loaded by your application. Of course you have to remove this servlet before uploading your application. Hope it helps people with their local debugging of jquery scripts or other javascript things.

How about having task 1 queue task 2 and task 2 queuing task 3?

> The use case is that I have 3 tasks that I want to insert into the > queue. Each task takes about 20 seconds to complete.  The challenge is > that task # 3 depends on task # 2, and task # 2 depends on task # 1. > The question is, how can I insert those 3 tasks and expect task 1 be > finished before task 2 starts, and task 2 be finished before task 3 > starts?

've been able to accomplish what you're doing with Selenium testing. If you're using GWT, then your integration testing and user acceptance probably won't be that far from each other.

> My question is this. What's the best way to use LocalServiceTestHelper > so that I can use my app like it has a persistent store? There is no > 'setUp' and 'tearDown' hooks like a JUnit test and the app runs in a > separate process within the IDE. (And in any case, I'm looking to do > integration testing where I want the state to be consistent across a > number of page requests.)

Another way of solving the problem is to have a Horse object with a "farmKey" field like so: class Horse {  @PrimaryKey  Key mKey  Key farmKey } Then to get horses on a farm you'd do a query on Horse.kind with farmKey equal to your farm key.  (Keys only query would make this faster) What's nice about this approach is that you don't need Horse key at all, just create a Horse object, give it the farm key, and persist it without worrying about it.

> > so a Farm can have some horses. I'd like to create a new horse, then > > put it on a farm, in one transaction.

> This requires Horse to be a descendant of Farm to be in the same   > entity group.  Therefore a horse could not move farms unless you   > delete and recreate it with a new Key.

To get the development environment working the plugin also requires access to the unzipped SDK as packaged by Google. The plugin tries to help you set this up (“gae:unpack”) but that failed for me. I was able to get stuff working by manually unzipping the SDK artifact downloaded directly from Google to the following directory: ~/.m2/repository/com/google/appengine/appengine-java-sdk/1.3.0/appengine-java-sdk-1.3.0

You’ll also notice in our appengine-web.xml that we substitute in our application name. By default this comes from the properties section of the pom.xml file (line 11).

 Twig is an alternative to the standard   persistence interfaces JDO and JPA, specifically designed to make the   most of the underlying datastore's unique features.

Twig is the only interface to support direct unowned relationships so   your code is not dependent on low-level datastore classes.  It is the   only interface to support OR queries by merging together multiple   queries, sorting them and filtering out duplicates at the lowest level   for performance.

Async datastore calls are not yet part of the low-level API.  Twig   uses the underlying Protocol Buffer layer classes to call   ApiProxy.makeAsyncCall() instead of makeSyncCall.  All the code is   open source so you can check out how its done.

> I'm still curious where does "method" name come from? That is just "Get" of "Put" or "RunQuery" etc.    I have also checked   in an implementation of Nick Johnsons ApiProxyHook which logs all this   info: LoggingApiProxyDelegate.  Its handy for seeing how what rpc   calls are being made.  If you want to discuss Twig specifics probably   best to do that here http://groups.google.com/group/twig-persist

protocol

ublic void doGet(HttpServletRequest req, HttpServletResponse resp)     throws IOException {    resp.setContentType("text/plain");    final DatastoreService datastore = DatastoreServiceFactory.getDatastoreService();    final Query query = new Query("Table/Entity Name");    //query.addSort(Entity.KEY_RESERVED_PROPERTY, Query.SortDirection.DESCENDING);    for (final Entity entity : datastore.prepare(query).asIterable()) {        resp.getWriter().println(entity.getKey().toString());        final Map<String, Object> properties = entity.getProperties();        final String[] propertyNames = properties.keySet().toArray(            new String[properties.size()]);        for(final String propertyName : propertyNames) {            resp.getWriter().println("-> " + propertyName + ": " + entity.getProperty(propertyName));        }    }}

You will only find "unowned relationships" terminology in Google docs. This "unowned relationships" in the GAE/J docs is where you have a field that is a "Key" or a Collection/Map/array of keys. So no *real* relation, just some implicit relation by that "key". You have to manage these keys yourself, and you tie your code to GAE/J by using them.

All you can do is fetch the entities of the type you want from the datastore and delete them one by one. (call datastore.delete(Iterable<Entity>))This way you can delete about 1000 entities at each request... There is no way to delete all entities of a Kind by a single api call.

> > If there is a way to list current Kinds or select all entities of any > > kind I could manage this.

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.

About loading request/performance, there're lots of discussions that you can find in the groups, please just try google it. Here are some notes based on reading those. Latency causes by 1- time to start new JVM 2- time to load your application To reduce load time by 1) others star request to a) pay to reserve JVM b) request Google to load your app before start dispatch request to that instance c) accept the situation For 2) we try to a- try to use/replace frameworks with light-weight ones: datastore access framework, MVC framework,... b- try to limit calculation in your index page to alleviate the impact of loading request c- design your object model based on your need, so that you do calculation at insert time, not at query time. For example, in my app, if I want to report on year and quarter, then I have 5 summary "record" for those, instead of querying and computing those d- caching result. For example, If I know 1 one 5 piece of data above would be read frequently, then I will read those 5 all, and put into memcache for later use ... So it's application-specific, I don't know if each of above can help you. But only you who can know if which one of your code can be cached and how...