flask-vite-transporter 🚚

Transport Vite apps to Flask (or Quart)

pip install flask-vite-transporter

• flask-vite-transporter 🚚
  • How it works
    • The pyproject.toml file
    • List the Vite apps
    • Compiling the Vite apps
    • Transporting the Vite apps
    • What happens
    • Modes (--mode)
    • Only (--only)
  • Working with vite-transporter using Flask / Quart
    • The context processors
    • Flask Example
    • Quart Example
    • CORS
    • Update the Static URL Path
  • Running the demos
  • Things to note

How it works

The pyproject.toml file

The pyproject.toml file is used to store what Vite apps are available.

pyproject.toml:

[tool.flask_vite_transporter]
npm_exec = "npm"
npx_exec = "npx"
serve_app = "app_flask"
vite_app.frontend = "frontend"

The compiling of the Vite apps requires the npx and npm be available. You can use absolute paths here.

npm_exec is used to run npm install if your Vite app does not have the node_modules folder.

npx is used to run the Vite app build command.

serve_app is the Flask or Quart app package that will serve the Vite compiled files. For now this extension only works with the app package setup:

app_flask/
├── static
├── templates
└── __init__.py

vite_app.<reference> is vite_app.'reference in the flask app' = 'relative folder of the vite app'

You can send over multiple Vite apps to the serving app, and they will be accessible within template files using the reference value.

See Working with vite-transporter using Flask / Quart for more information about how to use references.

[tool.flask_vite_transporter]
npm_exec = "npm"
npx_exec = "npx"
serve_app = "app_flask"
vite_app.customer_portal = "frontends/customer"
vite_app.admin_portal = "frontends/admin"

List the Vite apps

You can see what apps can be compiled by running:

vt list

It will show: <reference>: <vite app source> => <serve app location>

Compiling the Vite apps

vt pack

This will create a dist folder in each Vite app directory with the compiled files.

Transporting the Vite apps

vt transport

This will move the compiled files to the serving app.

You can also run the pack and transport commands together:

vt pack transport

What happens

The Vite apps are compiled into a dist folder, the files contained in this folder are then moved to a folder called vite in the serving app.

Any js file that is compiled that contains an asset reference will replace assets/ with /--vite--/{reference}.

This requires that all assets in the Vite app stay in the assets folder, and are imported in the frontend project in a way that the Vite compile stage can find them.

Modes (--mode)

The Vite apps can be compiled in different modes by using the -m or --mode flag:

vt pack -m development
# or
vt pack -m your-named-mode

An example of pack and transport together:

vt pack -m dev transport
# or
vt pack transport -mode dev

These mode values are accessible via import.meta.env.MODE in the Vite app.

See Vite: Env Variables and Modes to find out more about Vite modes.

Only (--only)

If you have multiple frontends and only want to pack and transport one you can use the -o or --only flag to do that.

Here's an example:

[tool.flask_vite_transporter]
npm_exec = "npm"
npx_exec = "npx"
serve_app = "app_flask"
vite_app.customer_portal = "frontends/customer"
vite_app.admin_portal = "frontends/admin"

vt pack transport --only admin_portal

Working with vite-transporter using Flask / Quart

flask-vite-transporter creates a couple of Flask / Quart context processors that match the Vite apps to a Flask / Quart template.

The context processors

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    {{ vt_head('frontend') }}
    <title>Test</title>
</head>
<body>
{{ vt_body() }}
</body>
</html>

vt_head(
    reference: str  # The name of the reference used.
)

vt_body(
    root_id: str = "root",  # The id of the root element
    noscript_message: str = "You need to enable JavaScript to run this app.",
)

Flask Example

from flask import Flask, render_template

from flask_vite_transporter import ViteTransporter


def create_app():
    app = Flask(__name__)
    ViteTransporter(app)

    @app.route("/")
    def index():
        return render_template("index.html")

    return app

Quart Example

from quart import Quart, render_template

from flask_vite_transporter.quart import QuartViteTransporter


def create_app():
    app = Quart(__name__)
    QuartViteTransporter(app)

    @app.route("/")
    async def index():
        return await render_template("index.html")

    return app

CORS

Setting:

ViteTransporter(app, cors_allowed_hosts=["http://127.0.0.1:5003"])

This is to allow the Vite app to communicate with the app.

Update the Static URL Path

ViteTransporter(
  app, 
  cors_allowed_hosts=["http://127.0.0.1:5003"],
  static_url_path="/nested/system/--vite--"
)

vt pack transport -sup /nested/system/--vite--

This is used if you're using nested systems.

Note: It's recommended to remove this in production.

Running the demos

We will be using a package call pyqwe to run commands from the pyproject file. Installing the development requirements will install pyqwe:

pip install -r requirements/tests.txt

Use pyqwe to install the local version of flask-vite-transporter:

pyqwe install

The serve_app under tool.flask_vite_transporter is currently set to use the Flask demo app.

pyqwe flask_plus_vite

You should be able to visit the Flask app and the Vite app from the link in the terminal. Change something in the Vite app, save, then in a separate terminal run:

vt pack transport

The Vite app will be compiled, and the files will be moved to the Flask app. Visiting the Flask app from the link in the terminal should show the changes.

Things to note

When including credentials in fetch requests in the vite app. You must visit the serve app first to set the credentials.

For example, if the serve app is running on http://127.0.0.1:5001, you must visit this address first.

This won't be needed in production, as it's expected that the Vite app will be served from the same domain.