Python 使用 Flask 为使用 create-react-app 创建的前端提供服务

Serving a front end created with create-react-app with Flask

提问by Theo

I have a Flask back-end with API routes which are accessed by a React single page application created using create-react-app. When using the create-react-app dev server, my Flask back end works.

我有一个带有 API 路由的 Flask 后端，这些路由由使用 create-react-app 创建的 React 单页应用程序访问。使用 create-react-app 开发服务器时，我的 Flask 后端工作正常。

I would like to serve the built (using npm run build) static React app from my Flask server. Building the React app leads to the following directory structure:

我想npm run build从我的 Flask 服务器提供构建（使用）静态 React 应用程序。构建 React 应用程序会导致以下目录结构：

- build
  - static
    - css
        - style.[crypto].css
        - style.[crypto].css.map
    - js
        - main.[crypto].js
        - main.[crypto].js.map
  - index.html
  - service-worker.js
  - [more meta files]

By [crypto], I mean the randomly generated strings generated at build time.

通过[crypto]，我的意思是在构建时所产生的随机生成的字符串。

Having received the index.htmlfile, the browser then makes the following requests:

收到index.html文件后，浏览器会发出以下请求：

- GET /static/css/main.[crypto].css
- GET /static/css/main.[crypto].css
- GET /service-worker.js

How should I serve these files? I came up with this:

我应该如何提供这些文件？我想出了这个：

from flask import Blueprint, send_from_directory

static = Blueprint('static', __name__)

@static.route('/')
def serve_static_index():
    return send_from_directory('../client/build/', 'index.html')

@static.route('/static/<path:path>') # serve whatever the client requested in the static folder
def serve_static(path):
    return send_from_directory('../client/build/static/', path)

@static.route('/service-worker.js')
def serve_worker():
    return send_from_directory('../client/build/', 'service-worker.js')

This way, the static assets are successfully served.

这样，静态资产就成功服务了。

On the other hand, I could incorporate this with the built-in Flask static utilities. But I do not understand how to configure this.

另一方面，我可以将它与内置的 Flask 静态实用程序结合起来。但我不明白如何配置它。

Is my solution robust enough? Is there a way to use built-in Flask features to serve these assets? Is there a better way to use create-react-app?

我的解决方案足够健壮吗？有没有办法使用内置的 Flask 功能来服务这些资产？有没有更好的方法来使用 create-react-app？

回答by Jodo

import os
from flask import Flask, send_from_directory

app = Flask(__name__, static_folder='react_app/build')

# Serve React App
@app.route('/', defaults={'path': ''})
@app.route('/<path:path>')
def serve(path):
    if path != "" and os.path.exists(app.static_folder + '/' + path):
        return send_from_directory(app.static_folder, path)
    else:
        return send_from_directory(app.static_folder, 'index.html')


if __name__ == '__main__':
    app.run(use_reloader=True, port=5000, threaded=True)

Thats what I ended up with. So bascially catch all routes, test if the path is a file => send file => else send the index.html. That way you can reload the react app from any route you wish and it does not break.

这就是我的结局。所以基本上捕获所有路由，测试路径是否为文件 => 发送文件 => 否则发送 index.html。这样你就可以从你想要的任何路线重新加载反应应用程序，它不会中断。

回答by Pranay Aryal

First do npm run buildto build the static production files as mentioned by you above

首先做npm run build上面提到的构建静态生产文件

from flask import Flask, render_template

app = Flask(__name__, static_folder="build/static", template_folder="build")

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

print('Starting Flask!')

app.debug=True
app.run(host='0.0.0.0')

Unfortunately, I don't think you can get it work with the development hot-reload.

不幸的是，我认为您无法通过开发热重载来实现它。

回答by Lukasz Madon

The accepted answer does not work for me. I have used

接受的答案对我不起作用。我用过了

import os

from flask import Flask, send_from_directory, jsonify, render_template, request

from server.landing import landing as landing_bp
from server.api import api as api_bp

app = Flask(__name__, static_folder="../client/build")
app.register_blueprint(landing_bp, url_prefix="/landing")
app.register_blueprint(api_bp, url_prefix="/api/v1")


@app.route("/")
def serve():
    """serves React App"""
    return send_from_directory(app.static_folder, "index.html")


@app.route("/<path:path>")
def static_proxy(path):
    """static folder serve"""
    file_name = path.split("/")[-1]
    dir_name = os.path.join(app.static_folder, "/".join(path.split("/")[:-1]))
    return send_from_directory(dir_name, file_name)


@app.errorhandler(404)
def handle_404(e):
    if request.path.startswith("/api/"):
        return jsonify(message="Resource not found"), 404
    return send_from_directory(app.static_folder, "index.html")


@app.errorhandler(405)
def handle_405(e):
    if request.path.startswith("/api/"):
        return jsonify(message="Mehtod not allowed"), 405
    return e

回答by pankaj

A working solution here. Ever thought why we need two separate folders for staticand templates. To segregate the mess, right? But, it's a problem with the production build since it has one folder for both staticand templatestype of files and all dependencies are linked like that.

这里有一个可行的解决方案。有没有想过为什么我们需要两个单独的文件夹static和templates. 为了隔离混乱，对吧？但是，它与生产版本的问题，因为它有两个一个文件夹static和templates类型的文件和所有相关性链接这样。

The buildfolder will be served if you consider it both staticand templates.

build如果您同时考虑static和 ，则将提供该文件夹templates。

Use something like this

使用这样的东西

from flask import Flask, render_template

app = Flask(__name__, static_url_path='',
                  static_folder='build',
                  template_folder='build')

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

Your flask app will run fine.

您的烧瓶应用程序将运行良好。