The Gnucash mentor students

Gnucash, a free accounting program for Linux, Microsoft Windows, and Apple Macintosh OSX, had its second opportunity to mentor students in the Google Summer of Code program this summer. Two of our three students successfully completed their projects.

Muslim Chochlov wrote unit tests for several critical modules of Gnucash’s core Query Object Framework. This is an important first step to some necessary refactoring of the framework so that Gnucash can move from an in-memory processing model to a transactional database model allowing simultaneous multiple user access.

Nitish Dodagetta extended the experimental Qt GUI “Cutecash” (Gnucash’s primary GUI is Gtk+) by writing a unified accounting transaction entry window. The Gnucash development team is investigating Qt and C++ as a future direction for Gnucash, and this struck a chord for Google Summer of Code students: half of the proposals we received from the student applicants prior to the start of the program were for Cutecash projects.
Overall we were pleased with the progress we made this summer; we found that the successful students leveraged the work of their mentors and moved forward some important aspects of the project. We’re continuing to work with the students this fall, integrating them into the regular development team. Mentoring up-and-coming programmers is very rewarding, and we enjoy encouraging them to use their skills for altruistic goals.

App Engine 1.5.2 SDK Released


As the summer heat descends on the Northern Hemisphere we thought we’d release our newest App Engine version with some changes that are sure to keep you playing around in the cool, air-conditioned indoors (hey, you don’t want your computer to overheat, right?).

Production Changes

  • Adjustable Scheduler Parameters – As we previously discussed, we are introducing two scheduler knobs (okay, they actually look like sliders) that will allow you to control some of the parameters that influence how many Instances run your application. Today you will be able to set the minimum pending latency and maximum number of idle instances for your application.

Datastore Changes

  • Advanced Query Planning – We are removing the need for exploding indexes and reducing the custom index requirements for many queries. The SDK will suggest better indexes in several cases and an upcoming article will describe what further optimizations are possible.
  • Namespaced Datastore Stats – Now, in addition to getting overall datastore stats, we are providing a new option to query datastore stats per namespace.

Task Queue Changes

  • New Task Queue details page – We’ve revamped the Task Queue details page in the Administration Console to provide more information about the tasks being run. You can now see the headers included in the enqueued task, the payload, and information from previous task runs.
  • 1MB Pull Task Size – It’s our belief that there is only one way for size limits to go – and that’s up! So with this release we’ve increased the size for pull tasks to 1MB.
  • Pull queue lease modification – We’ve introduced a new method for Pull Queues that allows you to extend the lease on existing tasks if the initial lease on the task was insufficient.

Lastly, we have some exciting news related to the experimental Go runtime. While it still remains experimental, starting with 1.5.2, all HRD apps will have access to the Go runtime in production.

As always, there are also some small features and bug fixes, the full list of which can be found in our release notes (Python, Java). We look forward to your feedback and questions in our forum.

Announcing App Engine 1.4.3. Release

Just in time for spring, we have a new App Engine release to bring our Java and Python runtimes even closer to parity. For Python, we’ve launched a test library to match the existing Java testing framework, and for Java we’ve introduced the Deferred and Remote APIs. This release also introduces a new Blobstore writing feature, the experimental release of the Prospective Search API in Python, and a few goodies for Task Queue and Cron users.


  • Prospective Search API: The experimental Prospective Search API allows Python runtime users to detect and take action on datastore entities that match certain criteria when they are written. For the experimental release, users will be allowed 10,000 subscriptions with the Prospective Search API. Pricing will be announced once the feature is fully launched.
  • Testbed Unit Test Framework: The Testbed suite for Python provides an easy interface for using App Engine API stubs in integration tests similar to the previously existing Java Testing Framework. You can create tests for your application that do not rely on calling App Engine production services, which speeds up the time your tests take to complete, and eliminates dependencies for your test on external services. Here at Google, we’re well known for our testing culture, and we hope that this API will allow you to develop more stable code more quickly.


  • Concurrent Requests: Until now, Java applications relied on starting additional instances to dynamically scale up for higher traffic levels. Now with support for concurrent requests, each application instance may serve multiple user requests at the same time. To start, ensure your application’s code is threadsafe, then enable concurrent requests by adding the flag to your appengine-web.xml.
  • Java Remote API and Deferred API support: The Remote API and Deferred API libraries have been supported in Python for awhile, and now they can be used with Java, too! The Remote API allows you to perform operations on your application’s datastore from your local machine. This is particularly useful for work that is not well-suited to App Engine’s request/response model. The Deferred API allows users to more easily write and execute ad hoc tasks. Our docs contain more information and examples on how to use the Remote API and Deferred API in Java App Engine.

New and changed APIs

  • Files API: The new Files API in Python and Java allow you to pragmatically read and write data using Blobstore. This API can be used to generate reports, export data, or do anything that your heart desires that requires large, binary objects.

Serving Changes

  • Task Queue and Cron update: We’ve addressed some of your top requested items for Task Queues and Cron. With this release, you can now configure the specific application version to which a task queue or cron job will send requests. For those wanting to schedule cron jobs with a range syntax like “every 5 minutes from 11:00 to 17:00”, that too is available in the 1.4.3 release. Last, but not least, the Admin Console Task Queues page now displays a more accurate estimate of queue size for queues containing more than 2000 tasks.

Coming soon

Finally, we have a pre-announcement about the 1.4.4 release. In 1.4.0, we introduced a feature that allowed users to download code that they’ve deployed to App Engine. In 1.4.2 we released admin roles allowing for Owners. When 1.4.4 is released, we plan on including a change that allows both the person who uploaded the code to download it, as well as the Owner(s) of the project (as listed in the Admin Console). In preparation for this, be sure to properly assign roles to all developers on your App Engine application in the Admin Console. Alternatively, you will still be able to permanently disable the code download feature for your application.

That’s it for now, for additional information read the full release notes, including all new features and issues fixed for Java and Python. All feedback is welcome and encouraged in our groups.