Important
Development on this package has moved to Plain and will continue there. Existing releases will remain published and I encourage you to fork this repo if you need to make changes.
Heavily inspired by rails/importmap-rails, this app adds a simple process for integrating import maps into Django.
This is a new project and it hasn't been used in production yet. But if you're looking to use import maps with Django, give it a try and tell us how it goes. The structure (and code) is pretty simple. Contributions are welcome!
You'll need to do four things to use django-importmap.
The TL;DR is:
- Add "importmap" to
INSTALLED_APPS - Create an
importmap.toml - Run
python manage.py importmap_generate - Use
{% importmap_scripts %}in your template
Do the equivalent of pip install django-importmap and add it to your INSTALLED_APPS list in your settings.py file.
# settings.py
INSTALLED_APPS = [
...
"importmap",
]You JavaScript dependencies are conveniently located in yourpyproject.toml file.
They are listed under [tool.importmap.dependencies] and you can add them there. The format is name = "version",
similar to how you would add a dependency to your package.json file.
# pyproject.toml
[tool.importmap.dependencies]
react = "17.0.2"
react-dom = "17.0.2"jspm.org generator is used lock and serve the dependencies,
but is basically just like installing them via npm i <npm package>@<version>.
To resolve the import map, you'll need to run python manage.py importmap_generate.
This will create importmap.lock (which you should save and commit to your repo) that contains the actual import map JSON (both for development and production).
You don't need to look at this file yourself, but here is an example of what it will contain:
{
"config_hash": "09d6237cdd891aad07de60f54689d130",
"importmap": {
"imports": {
"react": "https://ga.jspm.io/npm:[email protected]/index.js"
},
"scopes": {
"https://ga.jspm.io/": {
"object-assign": "https://ga.jspm.io/npm:[email protected]/index.js"
}
}
},
"importmap_dev": {
"imports": {
"react": "https://ga.jspm.io/npm:[email protected]/dev.index.js"
},
"scopes": {
"https://ga.jspm.io/": {
"object-assign": "https://ga.jspm.io/npm:[email protected]/index.js"
}
}
}
}The import map itself gets added by using {% load importmap %} and then {% importmap_scripts %} in the head of your HTML. This will include the es-module-shim.
After that, you can include your own JavaScript!
This could be inline or from static.
Just be sure to use type="module" and the "name" you provided when doing your JS imports (i.e. "react").
{% load importmap %}
<!DOCTYPE html>
<html lang="en">
<head>
{% importmap_scripts %}
<script type="module">
import React from "react"
console.log(React);
</script>
</head>
<body>
</body>
</html>When it renders you should get something like this:
<!DOCTYPE html>
<html lang="en">
<head>
<script async src="https://ga.jspm.io/npm:[email protected]/dist/es-module-shims.js"></script>
<script type="importmap">
{
"imports": {
"react": "https://ga.jspm.io/npm:[email protected]/dev.index.js"
},
"scopes": {
"https://ga.jspm.io/": {
"object-assign": "https://ga.jspm.io/npm:[email protected]/index.js"
}
}
}
</script>
<script type="module">
import React from "react"
console.log(React);
</script>
</head>
<body>
</body>
</html>You can include your own static files in the import map by passing kwargs to the {% importmap_scripts %} tag.
You can actually use this to include any additional imports, but by using {% static "name" as name_static %} you can get the URL to the static file.
{% load importmap static %}
<!DOCTYPE html>
<html lang="en">
<head>
{% static "my-script.js" as my_script_static %}
{% importmap_scripts myscript=my_script_static %}
<script type="module">
import MyScript from "myscript"
</script>
</head>
<body>
</body>
</html>To use django-importmap with Jinja2 templates,
you can add importmap to a customized Jinja environment.
TEMPLATES = [
{
"BACKEND": "django.template.backends.jinja2.Jinja2",
...
"OPTIONS": {
"environment": "app.jinja2.environment",
...
},
}
]Then in app/jinja2.py:
from django.conf import settings
from jinja2 import Environment
from importmap import Importmap
def environment(**options):
env = Environment(**options)
env.globals.update({"importmap": Importmap.json(development=settings.DEBUG)})
return envThen in your Jinja templates you can include a module shim and output the importmap variable like this:
<!DOCTYPE html>
<html lang="en">
<head>
<script async src="https://ga.jspm.io/npm:[email protected]/dist/es-module-shims.js"></script>
<script type="importmap">
{{ importmap|safe }}
</script>
<script type="module">
import React from "react"
console.log(React);
</script>
</head>
<body>
</body>
</html>To include your own static files in the import map,
you can pass a dictionary of names and URLs to the Importmap.json method:
from django.conf import settings
from django.templatetags.static import static
from jinja2 import Environment
from importmap import Importmap
def environment(**options):
env = Environment(**options)
env.globals.update(
{
"importmap": Importmap.json(
development=settings.DEBUG, extra_imports={"myjs": static("myjs.js")}
)
}
)
return envThis is partly an experiment, but honestly it's so simple that I don't think there can be much wrong with how it works currently.
Here's a list of things that would be nice to do (PRs welcome):
- Command to add new importmap dependency (use
^version automatically?) - Django check for comparing lock and config (at deploy time, etc.)
- Use deps to update shim version
- Preload option
- Vendoring option (including shim)
- More complete error handling (custom exceptions, etc.)