在颤振中从 PHP REST API 获取数据给出异常

Posted 2023-02-19

【中文标题】在颤振中从 PHP REST API 获取数据给出异常

【英文标题】：Fetchinng Data from PHP REST API in flutter gives exception

【发布时间】：2021-11-03 18:17:07

【问题描述】：

创建了一个用于在 php mysql 中获取数据的 REST API。部分数据已提取，而其他图像未提取，并出现以下异常消息。

到 REST API 的链接是 https://gujapp.geekconnects.co/getdata.php。

在任何网络上阻止应用 IP 一次使用后。我尝试过使用***，但一段时间后它也被阻止了。

======== Exception caught by image resource service ================================================
The following SocketException was thrown resolving an image codec:
OS Error: Connection reset by peer, errno = 104, address = gujapp.geekconnects.co, port = 59798

When the exception was thrown, this was the stack: 
Image provider: NetworkImage("https://gujapp.geekconnects.co/parentuploads/images2.png", scale: 1.0)
Image key: NetworkImage("https://gujapp.geekconnects.co/parentuploads/images2.png", scale: 1.0)
====================================================================================================

REST 服务的代码

import 'dart:convert';
import 'package:http/http.dart' as http;
import 'album.dart';


class Services 
  static var url = Uri.parse("https://gujapp.geekconnects.co/getdata.php");
  static Future<List<Album>> getPhotos() async
    try
      final response = await http.get(url);
      if(response.statusCode==200)
      
        List<Album> list=parsePhotos(response.body);
        return list;
      
      else
      
        throw Exception("Erroor");
      
    catch(e)
      throw new Exception(e.toString());
    
  

  static List<Album> parsePhotos(String responseBody) 
    final parsed = json.decode(responseBody).cast<Map<String, dynamic>>();
    return parsed.map<Album>((json)=>Album.fromJson(json)).toList();
  

专辑.dart

class Album
  String albumId;
  String id;
  String title;
  String url;
  String thumbnailUrl;

  Album(this.albumId,this.id,this.title,this.url,this.thumbnailUrl);

  factory Album.fromJson(Map<String,dynamic>json)
  
    return Album(
      albumId: json['albumId'] as String,
      id: json['id'] as String,
      title: json['title'] as String,
      url: json['url'] as String,
      thumbnailUrl: json['thumbnailUrl'] as String,
    );
  

gridcell.dart

import 'package:flutter/material.dart';
import 'album.dart';
import 'package:google_fonts/google_fonts.dart';

class AlbumCell extends StatelessWidget
  const AlbumCell(this.album);
  @required
  final Album album;

  @override
  Widget build(BuildContext context) 
    return Card(
      shape:RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(10.0),
      ),
      color: Colors.white,
      child: Padding(
        padding: EdgeInsets.all(10.0),
        child: Container(
          alignment: Alignment.center,
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.center,
            mainAxisAlignment: MainAxisAlignment.center,
            mainAxisSize: MainAxisSize.min,
            children: <Widget>[
              Flexible(
                child: ClipRRect(
                  borderRadius: BorderRadius.circular(10.0),
                  child: FadeInImage.assetNetwork(
                    placeholder: "images/no_image.png",
                    image: album.thumbnailUrl,
                    width: 100,
                    height: 100,
                  ),
                ),
              ),
              Padding(
                padding: EdgeInsets.fromLTRB(4.0,10.0,4.0,10.0),
                child: Text(
                  album.title,
                  maxLines: 2,
                  softWrap: true,
                  textAlign: TextAlign.center,
                  style: GoogleFonts.poppins(textStyle:TextStyle(fontSize: 13.0, fontWeight: FontWeight.w500)),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  

【参考方案1】：

尝试更改您的数据类 - Album

import 'dart:convert';

class Album 
  String albumId;
  String id;
  String title;
  String url;
  String thumbnailUrl;
  
  Album(
    required this.albumId,
    required this.id,
    required this.title,
    required this.url,
    required this.thumbnailUrl,
  );

  Map<String, dynamic> toMap() 
    return 
      'albumId': albumId,
      'id': id,
      'title': title,
      'url': url,
      'thumbnailUrl': thumbnailUrl,
    ;
  

  factory Album.fromMap(Map<String, dynamic> map) 
    return Album(
      albumId: map['albumId'],
      id: map['id'],
      title: map['title'],
      url: map['url'],
      thumbnailUrl: map['thumbnailUrl'],
    );
  

  String toJson() => json.encode(toMap());

  factory Album.fromJson(String source) => Album.fromMap(json.decode(source));

然后像这样转换数据

Future<List<Album>> getAlbums() async 
var url = Uri.parse("https://gujapp.geekconnects.co/getdata.php");

try 
  final response = await http.get(url);
  if (response.statusCode == 200) 
    final maps = jsonDecode(response.body).cast<Map<String, dynamic>>();

    return List.generate(maps.length, (i) 
      return Album.fromMap(maps[i]);
    );
   else 
    throw Exception("Erroor");
   
  catch (e) 
  throw new Exception(e.toString());
 


  @override
  Widget build(BuildContext context) 
    return Scaffold(
      body: Center(
        child: ElevatedButton(
          onPressed: () async 
            var albums = await getAlbums();
          ,
          child: Text("Run"),
        ),
      ),
    );
  

【讨论】：

仍然无法正常工作我认为这是我的托管服务提供商的问题。我正在使用共享主机 CPanel。

如果不完整查看代码，就无法理解错误在哪里。从项目中完全删除所有图像，并尝试从远程服务器添加图像