Codelab Custom Elements
The next generation of the codelab elements without any framework or library dependencies, only the Custom Elements standard spec.
If this is a release bundle, produced with a bazel build :bundle command,
you should see codelab-elements.js, codelab-elements.css and other files,
ready to be added to an HTML page like the following. Only relevant parts are shown:
A codelab demo Contents of the first step. Contents of the second step. You can download the latest version from https://github.com/googlecodelabs/codelab-elements.
Dev environment
All you need is bazel.
Currently, the build process requires bazel version 0.18.1.
After bazel is installed, try executing the following:
bazel test --test_output=all //codelab-elements/demo:hello_test
It will take some time at the first run because bazel will download and compile all dependencies needed to work with the code and run tests. This includes Google Closure library and compiler, Go language and browsers to run local JS tests on.
Building
Check out a demo HelloElement target. To build the element, execute the following:
bazel build //codelab-elements/demo:hello_bin
It should output something like this:
INFO: Analysed target //demo:hello_bin (0 packages loaded).
INFO: Found 1 target...
Target //demo:hello_bin up-to-date:
bazel-bin/demo/hello_bin.js
bazel-bin/demo/hello_bin.js.map
INFO: Elapsed time: 0.716s, Critical Path: 0.03s
INFO: Build completed successfully, 1 total action
Testing
All elements should have their test targets. As a starting point, check out HelloElement tests:
bazel test --test_output=errors //codelab-elements/demo:hello_test
You should see something like this:
INFO: Elapsed time: 5.394s, Critical Path: 4.60s
INFO: Build completed successfully, 2 total actions
//codelab-elements/demo:hello_test_chromium-local PASSED in 4.6s
When things go wrong, it is usually easier to inspect and analyze output with debug enabled:
bazel test -s --verbose_failures --test_output=all --test_arg=-debug codelab-elements/demo/hello_test
Manual inspection from a browser
To browse things around manually with a real browser, execute the following:
bazel run //codelab-elements/tools:server
and navigate to http://localhost:8080.
Deploying the built artifacts to a CDN
We now store the built artifacts in a world-readable Google Cloud Storage bucket (gs://codelab-elements). The list of artifacts we need to serve from this bucket are as follows:
- codelab-elements.css
- native-shim.js
- custom-elements.min.js
- prettify.js
- codelab-elements.js
The manual process for deploying these artifacts is as follows:
cd googlecodelabs/tools # start at repo level
bazel build //... # build everything
mkdir pkg
cd pkg
unzip ../bazel-genfiles/bundle.zip
export SRC="codelab-elements.css native-shim.js custom-elements.min.js prettify.js codelab-elements.js codelab-index.css codelab-index.js"
gsutil -m cp -a public-read $SRC gs://codelab-elements
Then you need to include these artifacts using their full path, which is:
https://storage.googleapis.com/codelab-elements/FILE
where 'FILE' is replaced by one of the source files defined in the SRC variable above.
Here's an index.html obtaining the codelab-elements from Google Cloud Storage:
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, minimum-scale=1.0,initial-scale=1.0, user-scalable=yes">
<title>A codelab demo</title>
<link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Source+Code+Pro:400|Roboto:400,300,400italic,500,700|Roboto+Mono">
<link rel="stylesheet" href="https://fonts.googleapis.com/icon?family=Material+Icons">
<link rel="stylesheet" href="https://storage.googleapis.com/codelab-elements/codelab-elements.css">
</head>
<body>
<google-codelab-analytics gaid="UA-123"></google-codelab-analytics>
<google-codelab codelab-gaid="UA-345" id="codelab-demo" title="A codelab demo">
<google-codelab-step label="Overview" duration="1">
Contents of the first step.
</google-codelab-step>
<google-codelab-step label="Second" duration="10">
Contents of the second step.
</google-codelab-step>
</google-codelab>
<script src="https://storage.googleapis.com/codelab-elements/native-shim.js"></script>
<script src="https://storage.googleapis.com/codelab-elements/custom-elements.min.js"></script>
<script src="https://storage.googleapis.com/codelab-elements/prettify.js"></script>
<script src="https://storage.googleapis.com/codelab-elements/codelab-elements.js"></script>
</body>
</html>
NPM
The library is published on NPM.js at: https://www.npmjs.com/package/codelab-elements
We also support a build workflow using NPM. To build the library run fro the root of the repo:
# Install dependencies. This takes care of installing the right version of Bazel. npm install # Build the library npm run build # The output is a zip file under bazel-genfiles ls bazel-genfiles npm_dist.zip # Publish a new version of the library to NPM npm run distNotes
This is not an official Google product.