Blockly is a web-based, graphical programming editor. Users can drag blocks together to build an application. No typing required. Credit goes to these awesome developers and a small army of translators.

This repository contains the source code for the apps Blockly based 20 hour curriculum and Hour of Code. Information about Blockly can be found in the wiki.

• Quick Start
• Contributing

One of the node modules, node-canvas, depends on Cairo being installed.

Instructions for MacOSX using brew (instructions for other platforms can be found here):

1. Install XQuartz from here
2. export PKG_CONFIG_PATH="$PKG_CONFIG_PATH:/opt/X11/lib/pkgconfig"
3. brew update
4. brew install cairo

# Get the code
git clone https://github.com/code-dot-org/blockly.git blockly
cd blockly

# Machine setup (OSX with Homebrew)
brew install node
npm install -g grunt-cli

# Perform first full build
npm install
MOOC_DEV=1 grunt build

1. From the Dashboard project, follow these instructions to set up a symlink to your development copy of blockly.

• Check your symlink if you find your changes are not showing up within dashboard. You may accidentally replace your symlink with the pre-built vendor version (e.g., if you're switching branches or stashing changes).

1. When you run later builds, your results should show up in Dashboard.

To run a full build (minus localization):

MOOC_DEV=1 grunt build

• MOOC_DEV=1 builds a 'debug' version with more readable javascript
• grunt rebuild does a clean before a build

grunt dev
open http://localhost:8000

This will serve a few sample blockly apps at http://localhost:8000.

Note: this does not update asset files. For that, use a full grunt build.

To have grunt rebuild only a single app, use the MOOC_APP parameter:

MOOC_APP=studio grunt dev

grunt build # run a build before testing
grunt test

• If you see an error like ReferenceError: Blockly is not defined or notes about missing npm packages, double check that you've run grunt build before grunt test
• grunt test will also be run via Travis CI when you create a pull request

To run an individual test, use the --grep option to target a file or Mocha describe identifier:

grunt test --grep myTestName # e.g., 2_11, or requiredBlockUtils

To debug tests using the node-inspector Chrome-like debugger:

npm install -g node-inspector
node-inspector &
# open debugger URL
node --debug-brk $(which grunt) --grep='testname'
# This will breakpoint your inspector at the beginning of that test

• You can add new test files as /test/*Tests.js, see /test/feedbackTests.js as an example of adding a mock Blockly instance
• Blockly tests typically target built files in the build/js folder

1. Check out blockly-core as a sibling directory to blockly.
2. ./build_with_core.sh debug

• The debug flag builds debug versions of both blockly-core and blockly, suitable for debugging

1. grunt dev

It's especially important to test your changes with localization when modifying layouts. We support right-to-left languages and have some special layout tweaks embedded in the CSS to support that.

Running a full localization build can take several minutes. Since localization re-builds javascript files for many languages, the default build target locales are en_us and en_ploc (pseudolocalized). To build all available locales, specify MOOC_LOCALIZE=1 in your environment when running a task:

MOOC_LOCALIZE=1 grunt rebuild

Note: if you're running the grunt dev live-reload server and get the error too many open files after a localization build, try increasing the OS open file limit by running ulimit -n 1024 (and adding it to your .bashrc).

To get new strings localized using CrowdIn, we currently run a script in a private repository. Contact a code.org engineer to trigger an update.

To add a new package using npm, e.g., lodash, run: npm i --save-dev lodash

• --save-dev adds the dependency to node's package.json, freezing the current version
• Because the build process is done in dev mode, include dependencies as devDependencies rather than production dependencies

We'd love to have you join our group of contributors!

For notes on our pull process, where to find tasks to work on, etc.—see the Dashboard contribution guide.

• In general follow Google's javascript style guide.
• 80 character line length.
• 2 space indent.
• 4 space indent on long line breaks.
• grunt jshint should report 0 warnings or errors.