ember-trace

Generate Graphviz dataflow graphs for your Ember app.

What & Why?

Given some templates:

app/templates/
├── application.hbs
└── components
    ├── x-bar.hbs
    └── x-foo.hbs

Running ember trace:

ember trace app/templates/application.hbs | dot -Tpng > docs/images/example.png

Will produce something like this:

These graphs can be useful for analysing how data flows through Ember apps. Put another way, they’re a visual tool for answering questions like “where did this value come from?” and “who owns it?”.

Installation

ember install ember-trace

Then download and install GraphViz.

Usage

ember trace app/templates/my-route.hbs

This command emits the graph to stdout in Graphviz DOT format. You’ll probably want to pipe it straight into the dot program to generate the graph.

ember trace app/templates/my-route.hbs | dot -Tpdf > graph.pdf

Some ember-cli addons emit deprecation warnings on stdout, so you’ll want to strip those before handing it over to dot.

ember trace app/templates/my-route.hbs | sed 's/^DEPRECATION.*$//g' | dot -Tpdf > graph.pdf

History

Created as an experiment in early 2018 by the Human Interface Team at Heroku.