Skip to content


Switch branches/tags

Name already in use

A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?

Latest commit


Git stats


Failed to load latest commit information.
Latest commit message
Commit time

A web front-end for Myria

This is a Google App Engine app.

Build Status


You must have the Google App Engine SDK for Python installed locally. During setup, be sure to select the option to create symbolic links to the Python utilities so that they are available from the command line.

Initial setup

  1. This project uses the UW eScience Raco project. We have configured it as a submodule. After cloning this repository, you must run:
git submodule init
git submodule update
Then setup the module as described in the [Raco README](
  1. The PLY library used to parse programs in the Myria language uses a precompiled in the raco submodule. This file is not required, but dramatically speeds up the parser load time (which happens for every request to the app). To generate it, run
scripts/myrial examples/reachable.myl

in the raco subdirectory.

  1. Launch the local App Engine emulator. I prefer to use Google's GoogleApp EngineLauncher application (installed with the SDK), which provides a nice GUI interface to control the emulator. From the menu select Add Existing Application, and add the myria-web/appengine directory.

Alternatively, from the command line, you may launch: /path/to/myria-web/appengine

And then point your browser at localhost:8080 to view the application.

Changing the Myria Hostname

To change the Myria instance from the default (vega), modify appengine/, changing the hostname and port variables. Changes will reflect automatically in the GAE application at localhost:8080.

Which branch to be on

There are two notable branches in the myria-web repository: master and production.

Depending on your goals (modifying latest myria-web vs running a stable version of the interface), you may wish to switch to the production branch.

Updating the code

To update the submodule to the latest from master, run this code:

git submodule update --recursive --remote

(Might also require beforehand:

git submodule init


Run the tests

Install the developer dependencies.

pip install -r requirements-dev.txt

Download a local copy of Google App Engine

curl -O
unzip -q


nosetests test/ test/ -w appengine --with-gae --gae-lib-root=google_appengine

Run without Google App Engine

It is possible to run myria-web without a dependence on Google App Engine. Right now, myria-web uses the paste module to run the web application.

Install the developer dependencies.

pip install -r requirements-dev.txt

Do steps 1 and 2 only from Initial setup.

Finally, start the server.

cd appengine


The Google App Engine GUI has a Logs button that can be helpful for diagnosing issues with the Myria web app.