python - 解决方案不起作用 - 错误状态：平台不允许使用不安全的 HTTP

Question

我正在尝试使用flutter作为前端和python作为后端来编写一个应用程序。我正在用python创建一个rest api，现在尝试用flutter向它发送请求。

在颤振中运行附加代码时出现以下错误： SocketException: OS Error: Connection denied, errno = 111, address = 127 .0.0.1, port = 43360

我尝试使用 IPv4 的地址切换本地主机并得到错误：错误状态：平台不允许不安全的 HTTP：http://IPv4_adress:5000/product/1。

我尝试了我在网上找到的所有解决方案，比如添加到 myapp\android\app\src\debug\AndroidManifest.xml ：

<application android:usesCleartextTraffic="true">
</application>

我还尝试将 HTTP 更改为 HTTPS，但我只收到错误消息：SocketException: OS Error: Connection timed out, errno = 110, address = 10.100.102.15, port = 59658

我重新加载了应用程序，但错误仍然存​​在。

我使用了此链接https://flutter.dev/docs/cookbook/networking/fetch-data中的指南，它运行良好。在我将专辑类更改为产品类并将 url 更改为我的 rest api url 后发生错误。我使用带有flask和sqlalchemy的python创建了rest api，我可以使用邮递员和chrome向它发送请求。

颤振代码：

import 'dart:async';
import 'dart:convert';

import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;

Future<Product> fetchProduct() async {
  final response = await http.get(Uri.parse('http://127.0.0.1:5000/product/1'));

  if (response.statusCode == 200) {
    // If the server did return a 200 OK response,
    // then parse the JSON.
    return Product.fromJson(jsonDecode(response.body));
  } else {
    // If the server did not return a 200 OK response,
    // then throw an exception.
    throw Exception('Failed to load Product');
  }
}

class Product {
  final int id;
  final String name;
  final String description;
  final double price;
  final int qty;

  Product({
    @required this.id,
    @required this.name,
    @required this.description,
    @required this.price,
    @required this.qty,
  });

  factory Product.fromJson(Map<String, dynamic> json) {
    return Product(
      id: json['id'],
      name: json['name'],
      description: json['description'],
      price: json['price'],
      qty: json['qty'],
    );
  }
}

void main() => runApp(MyApp());

class MyApp extends StatefulWidget {

  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  Future<Product> futureProdcut;

  @override
  void initState() {
    super.initState();
    futureProdcut = fetchProduct();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Fetch Data Example',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Fetch Data Example'),
        ),
        body: Center(
          child: FutureBuilder<Product>(
            future: futureProdcut,
            builder: (context, snapshot) {
              if (snapshot.hasData) {
                return Text(snapshot.data.name);
              } else if (snapshot.hasError) {
                print(snapshot.error);
                return Text('${snapshot.error}');
              }

              // By default, show a loading spinner.
              return const CircularProgressIndicator();
            },
          ),
        ),
      ),
    );
  }
}

Python代码：

from flask import Flask, request, jsonify
from flask_sqlalchemy import SQLAlchemy
from flask_marshmallow import Marshmallow
import os

# init app
app = Flask(__name__)
basedir = os.path.abspath(os.path.dirname(__file__))
#database
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///' + os.path.join(basedir, 'db.sqlite')
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
# Init db
db =SQLAlchemy(app)
# Init ma
ma = Marshmallow(app)

#Product Class/model
class Product(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(100), unique=True)
    description = db.Column(db.String(200))
    price = db.Column(db.Float)
    qty = db.Column(db.Integer)

    def __init__(self, name, description, price, qty):
        self.name = name
        self.description = description
        self.price = price
        self.qty = qty

# Product Schema
class ProductSchema(ma.Schema):
    class Meta:
        fields = ('id', 'name', 'description', 'price', 'qty')

# Init Schema
product_schema = ProductSchema()
products_schema = ProductSchema(many=True)

# Create a Product
@app.route('/product', methods=['POST'])
def add_product():
    name = request.json['name']
    description = request.json['description']
    price = request.json['price']
    qty = request.json['qty']

    new_product = Product(name, description, price, qty)

    db.session.add(new_product)
    db.session.commit()

    return product_schema.jsonify(new_product)

# Get All Products
@app.route('/product', methods=['GET'])
def get_prodcuts():
    all_products = Product.query.all()
    result = products_schema.dump(all_products)
    print(result)
    print(type(result))
    return jsonify(result)

# Get Single Products
@app.route('/product/<id>', methods=['GET'])
def get_prodcut(id):
    product = Product.query.get(id)
    return product_schema.jsonify(product)

# Update a Product
@app.route('/product/<id>', methods=['PUT'])
def update_product(id):
    product = Product.query.get(id)
    name = request.json['name']
    description = request.json['description']
    price = request.json['price']
    qty = request.json['qty']

    product.name = name
    product.description = description
    product.price = price
    product.qty = qty

    db.session.commit()

    return product_schema.jsonify(product)

# run server
if __name__ == '__main__':
    app.run(debug=True)

标签： pythonflutterhttpflaskrest