React Render

Render React components on the server side in Django, also called "isomorphic React". You would do this for faster page loads, to make it friendlier to web crawlers and for SEO.

Example

from react_render.django.render import render_component

props = {
    'foo': 'bar',
    'woz': [1,2,3],
}

rendered = render_component('path/to/component.js', props=props)

print(rendered)

How it works

It works by having a NodeJS service on the same server that can render the React components. The Python just uses a simple HTTP API to send the context and the file path over to the service, and it responds with the rendered HTML.

Documentation

• Installation
• render_component()
• RenderedComponent
• Running the tests
• react-service settings

Installation

npm install react-render-service --save
pip install react-render-client

Optional: Point it to the service in your settings.py

REACT_SERVICE_URL = 'http://localhost:63578/render'

Start the node server which hosts the renderer.

react-service --debug

render_component()

Renders a component to its initial HTML.

Returns a RenderedComponent instance, which can be passed directly into templates to output the component's HTML.

Arguments:

• path_to_source — a path to a JS file which exports the component. If the path is relative, django's static file finders will be used to find the file. NOTE Must be compiled JS, not JSX.
• props optional — a dictonary that will be serialised to JSON and passed to the component during the renderering process.
• to_static_markup optional — a boolean indicating that React's renderToStaticMarkup method should be used for the rendering. Defaults to False, which causes React's renderToString method to be used.
• json_encoder optional — a class which is used to encode the JSON which is sent to the renderer. Defaults to django.core.serializers.json.DjangoJSONEncoder.
• timeout optional - override the service timeout.

RenderedComponent

The result of rendering a component to its initial HTML. RenderedComponents can be passed directly into templates where they output the generated HTML.

# Render the component
my_component = render_component(...)

# Print the generated HTML
print(my_component)

<!-- Insert the generated HTML into your template -->
{{ my_component }}

RenderedComponents have a helper method, render_props, which outputs your JSON-serialized props. This allows you to reuse the encoded form of your props on the client-side.

<script>
    var myProps = {{ my_component.render_props }};
</script>

react-service settings

• --host Bind to a different interface, by default this is localhost.
• --port Bind to a different port. By default it is 63578
• --watch Enable developer mode where it will automatically re-load the bundles if they change.
• --whitelist Restrict the directory that the service can access. By default, the service will attempt to load any arbitrary path it is given. Can also be set via the REACT_WHITELIST environment variable.

Django settings

• REACT_SERVICE_URL
  • Customer URL for the render service (eg. for changing port)
  • Default: http://localhost:63578/render
• REACT_FAIL_SAFE
  • If there is a problem with the service, do not raise an exception, and return empty HTML (allowing the client-side JS to take over)
  • Default: False
• REACT_TIMEOUT
  • How long (in seconds) should it wait for nodejs to render the component
  • Default: 10

Running the tests

mkvirtualenv react-render
pip install -e .
cd tests
npm install
npm run build
cd ..
python runtests.py