Django使用AJAX调用本身写的API接口

Django使用AJAX调用本身写的API接口

***

具体代码和数据已上传到github

https://github.com/PythonerKK/eleme-api-by-django-restful-framework
***

在这个例子中，咱们将使用Django编写饿了么高校外卖商家查询API接口，而且使用AJAX技术来实现API接口的使用，包括使用ajax get方法加载更多数据，使用ajax方法来更新、修改、新增、删除数据。利用API能够作到先后端分离，为开发web应用提供了便利。

安装rest framework

首先使用Pycharm新建一个Django项目，而且使用virtualenv或者pipenv虚拟环境

建立成功会自动安装Django2.1和所需依赖，restframework框架须要本身手动安装

//激活虚拟环境安装如下
(venv)$ pip install djangorestframework
(venv)$ pip install django-filter 
(venv)$ pip install pytest
(venv)$ pip install pytest-django 
//因为笔者使用Postgresql数据库，因此还须要安装如下
(venv)$ pip install psycopg2
//使用mysql数据库安装以下
(venv)$ pip install pymysql

准备数据来提供服务

数据来源：饿了么爬虫
数据内容：全国全部大学附近的外卖商家Top20
数据须要导入数据库

Django编写rest api接口

项目结构

settings.py.

// 安装的app以下
INSTALLED_APPS = [
    #...
    'rest_framework',
    'django_filters',
    'api.apps.ApiConfig',
    'front.apps.FrontConfig',
]
//restframework 配置以下

REST_FRAMEWORK = {
//这里配置了分页处理，每页最多20个项目
'DEFAULT_PAGINATION_CLASS':'api.custompagination.LimitOffsetPaginationWithUpperBound',
    'PAGE_SIZE': 20,
    'DEFAULT_FILTER_BACKENDS': (
        //这里配置了排序、过滤、搜索器
        'django_filters.rest_framework.DjangoFilterBackend',
        'rest_framework.filters.OrderingFilter',
        'rest_framework.filters.SearchFilter',
    ),
    //这里配置了用户认证，管理员才能够更改内容，未登陆不能更改
    'DEFAULT_AUTHENTICATION_CLASSES':(
        'rest_framework.authentication.BasicAuthentication',
        'rest_framework.authentication.SessionAuthentication',
    ),
    //这里配置了访问次数限制，过多会返回429错误 too many requests
    'DEFAULT_THROTTLE_CLASSES': (
        'rest_framework.throttling.AnonRateThrottle',
        'rest_framework.throttling.UserRateThrottle',
    ),
    //这里配置了访问次数，anon表明匿名用户，user表明已登陆用户，entries是我本身设置的做用域，300/hour表明最多300次每小时
    'DEFAULT_THROTTLE_RATES': {
        'anon': '300/hour',
        'user': '100/hour',
        'entries': '200/hour',
    },
    'DEFAULT_VERSIONING_CLASS':'rest_framework.versioning.NamespaceVersioning',
}

models.py.

from django.db import models

class Entry(models.Model):
    city = models.CharField(max_length=50)
    school = models.CharField(max_length=100)
    link = models.CharField(max_length=100,null=True,default='null')
    name = models.CharField(max_length=200)
    lat = models.CharField(max_length=20,null=True,default='0.0')
    lng = models.CharField(max_length=20,null=True,default='0.0')
    address = models.CharField(max_length=200,null=True,default='null')
    distance = models.CharField(max_length=20,null=True,default='0')
    time = models.CharField(max_length=20,null=True,default='0:00')
    contact = models.CharField(max_length=200,null=True,default='null')
    score = models.CharField(max_length=10,null=True,default='0')
    comments = models.CharField(max_length=20,null=True,default='0')
    sell = models.CharField(max_length=20,null=True,default='0')
    image = models.CharField(max_length=200,null=True,default='null')
    owner = models.ForeignKey('auth.User',related_name='entries',on_delete=models.CASCADE)
    # class Meta:
    #     ordering = ('name',)
    def __str__(self):
        return self.name

serializers.py.

from rest_framework import serializers
from api.models import Entry
//这里继承自超连接模型序列器，用于把数据转换为json格式，而且显示连接
class EntrySerializer(serializers.HyperlinkedModelSerializer):
    owner = serializers.ReadOnlyField(source='owner.username')
    class Meta:
        model = Entry
        fields = ('url','pk','name','city','school','link','lat','lng','address','distance','time','contact',
                  'score','comments','sell','image','owner')

views.py.

from rest_framework import generics
from rest_framework.response import Response
from rest_framework.reverse import reverse
from api.models import Entry
from api.serializers import EntrySerializer
from rest_framework import permissions
from rest_framework.permissions import IsAuthenticated
from rest_framework.throttling import ScopedRateThrottle
from api import custompermission

//这里是获取全部数据，可实现HTTP get、Post、Option操做
class EntryList(generics.ListCreateAPIView):
    //限流自定义做用域
    throttle_scope = 'entries'
    throttle_classes = (ScopedRateThrottle,)
    queryset = Entry.objects.all()
    serializer_class = EntrySerializer
    name = 'entry-list'
    filter_fields = ('city','school','name')
    search_fields = ('school','city')
    ordering_fields = ('city')
    
    //管理员才能post操做建立新的数据
    permission_classes = (
        permissions.IsAuthenticatedOrReadOnly,
        custompermission.IsCurrentUserOwnerOrReadOnly,
    )

    def perform_create(self, serializer):
        serializer.save(owner=self.request.user)
        
//这里是获取具体某一项的数据，可实现HTTP GET、PUT、PATCH、Option操做
class EntryDetail(generics.RetrieveUpdateDestroyAPIView):
    throttle_scope = 'entries'
    throttle_classes = (ScopedRateThrottle,)
    queryset = Entry.objects.all()
    serializer_class = EntrySerializer
    name = 'entry-detail'

    permission_classes = (
        permissions.IsAuthenticatedOrReadOnly,
        custompermission.IsCurrentUserOwnerOrReadOnly,
    )

//api根目录
class ApiRoot(generics.GenericAPIView):
    name = 'api-root'
    def get(self, request, *args, **kwargs):
        return Response({
            'entries': reverse(EntryList.name, request=request),
        })

urls.py.

from django.urls import path
from api import views
urlpatterns = [
    path('entries/', views.EntryList.as_view(), name=views.EntryList.name),
    path('entry-detail/<int:pk>', views.EntryDetail.as_view(), name=views.EntryDetail.name),
    path('', views.ApiRoot.as_view(), name=views.ApiRoot.name)
]

ele/urls.py.

from django.urls import path,include

urlpatterns = [
    path('v1/',include('api.urls')),
    path('v1/api-auth/',include('rest_framework.urls')),
    path('',include('front.urls'))
]

如下为启动界面

到此为止很是简单的api就写完了，接下来就是自动化测试是否达到预期效果。
如图，测试经过！

在程序中调用刚刚写好的api

建立一个新的app而且添加到settings.py里面

(venv)$ python manage.py startapp front

作好的效果以下：点击加载更多会触发ajax
因为篇幅有限，这里贴出js代码
使用ajax get请求刚刚写好的api接口而且添加到表格中
myjs.js.

$('#load-more').click(function () {
        $.ajax({
            method:'GET',
            url:api_url,
            dataType:'json',
            success:function (data) {
                api_url = data['next'];
                if (api_url == null){
                    $('#load-more').val('已加载所有');
                    $('#load-more').attr('disabled',true);
                    //api_url这里就是刚刚写好的api接口
                    api_url = 'v1/entries/';
                }
                var results = data['results'];
                for (i=0;i<results.length;i++){
                    $('#ele-table-body').append(
                        '        <tr>\n' +
                        '            <th scope="col">'+results[i]['pk']+'</th>\n' +
                        '            <th scope="col">'+results[i]['city']+'</th>\n' +
                        '            <th scope="col"><a href="/detail/' + results[i]['pk'] +'">' + results[i]['name'] + '</a></th>\n' +
                        '            <th scope="col">'+results[i]['school']+'</th>\n' +
                        '            <th scope="col">'+results[i]['score']+'</th>\n' +
                        '        </tr>'
                    )
                }

            }
        })
    });

能够修改具体的一条数据，使用ajax patch方法提交数据。
注：PUT方法是修改全部数据，而PATCH方法是修改局部数据

myjs.js.

$('#edit-confirm-btn').click(function () {
        var name = $('#name').val();
        var distance = $('#distance').val();
        var adderss = $('#address').val();
        var time = $('#time').val();
        var score = $('#score').val();
        var comments = $('#comments').val();
        var sell = $('#sell').val();
        var pk = $('#pk').val();
        $.ajax({
            type:'PATCH',
            url:'/detail/' + pk,
            data:{
                "name": name,
                "distance": distance,
                "address": adderss,
                "time": time,
                "score": score,
                "comments": comments,
                "sell": sell,
            },

            success:function (data) {
                if (data.status == 'ok'){
                    console.log('success');
                    location.reload();
                }
            }
        })
    })

本文经过一个小例子介绍了如何使用Django调用本身写的api