1.安装:
    pip install django
    pip install djangorestframework
    pip install pygments  # 此模块用来使得代码可以突出显示
2。创建一个新的环境:
    virtualenv env
    source env/bin/activate
3.创建工程:
    cd  # cd 到你要创建工程的目录
    django-admin startproject tutorial
    cd tutorial
    python manage.py startapp snippets  # 创建webapi
4.配置:
    在settings.py的INSTALLED_APPS中配置:
    INSTALLED_APPS = (
    ...
    ‘rest_framework‘,
    ‘snippets.apps.SnippetsConfig‘,
    )
5.编辑snippets/models.py
    from django.db import models
    from pygments.lexers import get_all_lexers
    from pygments.styles import get_all_styles
    LEXERS = [item for item in get_all_lexers() if item[1]]
    LANGUAGE_CHOICES = sorted([(item[1][0], item[0]) for item in LEXERS])
    STYLE_CHOICES = sorted((item, item) for item in get_all_styles())
    class Snippet(models.Model):
        created = models.DateTimeField(auto_now_add=True)
        title = models.CharField(max_length=100, blank=True, default=‘‘)
        code = models.TextField()
        linenos = models.BooleanField(default=False)
        language = models.CharField(choices=LANGUAGE_CHOICES, default=‘python‘, max_length=100)
        style = models.CharField(choices=STYLE_CHOICES, default=‘friendly‘, max_length=100)
        class Meta:
            ordering = (‘created‘,)
6.初始化和迁移数据库
    python manage.py makemigrations snippets
    python manage.py migrate
7.创建序列化的类snippets/serializers.py
    from rest_framework import serializers
    from snippets.models import Snippet, LANGUAGE_CHOICES, STYLE_CHOICES
    class SnippetSerializer(serializers.Serializer):
        id = serializers.IntegerField(read_only=True)
        title = serializers.CharField(required=False, allow_blank=True, max_length=100)
        code = serializers.CharField(style={‘base_template‘: ‘textarea.html‘})
        linenos = serializers.BooleanField(required=False)
        language = serializers.ChoiceField(choices=LANGUAGE_CHOICES, default=‘python‘)
        style = serializers.ChoiceField(choices=STYLE_CHOICES, default=‘friendly‘)
        def create(self, validated_data):
            """
            Create and return a new `Snippet` instance, given the validated data.
            """
            return Snippet.objects.create(**validated_data)
        def update(self, instance, validated_data):
            """
            Update and return an existing `Snippet` instance, given the validated data.
            """
            instance.title = validated_data.get(‘title‘, instance.title)
            instance.code = validated_data.get(‘code‘, instance.code)
            instance.linenos = validated_data.get(‘linenos‘, instance.linenos)
            instance.language = validated_data.get(‘language‘, instance.language)
            instance.style = validated_data.get(‘style‘, instance.style)
            instance.save()
            return instance
8.使用ModelSerializer使得上面的代码更加简洁
    class SnippetSerializer(serializers.ModelSerializer):
        class Meta:
            model = Snippet
            fields = (‘id‘, ‘title‘, ‘code‘, ‘linenos‘, ‘language‘, ‘style‘)
    """
    重要的是要记住,ModelSerializer类并没有什么特别神奇的功能,它们只是创建序列化器类的快捷方式:
    一组自动确定的字段。
    create()和update()方法的简单默认实现。
    """
9. 配置snippets/views.py
from django.http import HttpResponse, JsonResponse
from django.views.decorators.csrf import csrf_exempt
from rest_framework.renderers import JSONRenderer
from rest_framework.parsers import JSONParser
from snippets.models import Snippet
from snippets.serializers import SnippetSerializer
@csrf_exempt
def snippet_list(request):
    """
    List all code snippets, or create a new snippet.
    """
    if request.method == ‘GET‘:
        snippets = Snippet.objects.all()
        serializer = SnippetSerializer(snippets, many=True)
        return JsonResponse(serializer.data, safe=False)
    elif request.method == ‘POST‘:
        data = JSONParser().parse(request)
        serializer = SnippetSerializer(data=data)
        if serializer.is_valid():
            serializer.save()
            return JsonResponse(serializer.data, status=201)
        return JsonResponse(serializer.errors, status=400)
@csrf_exempt
def snippet_detail(request, pk):
    """
    Retrieve, update or delete a code snippet.
    """
    try:
        snippet = Snippet.objects.get(pk=pk)
    except Snippet.DoesNotExist:
        return HttpResponse(status=404)
    if request.method == ‘GET‘:
        serializer = SnippetSerializer(snippet)
        return JsonResponse(serializer.data)
    elif request.method == ‘PUT‘:
        data = JSONParser().parse(request)
        serializer = SnippetSerializer(snippet, data=data)
        if serializer.is_valid():
            serializer.save()
            return JsonResponse(serializer.data)
        return JsonResponse(serializer.errors, status=400)
    elif request.method == ‘DELETE‘:
        snippet.delete()
        return HttpResponse(status=204)
"""
值得注意的是,有几个边缘情况我们目前没有正确处理。如果我们发送格式不正确的json,
或者使用视图无法处理的方法发出请求,那么我们将得到500个“服务器错误”响应。
不过,现在这样就可以了。
"""
10.配置snippets/urls.py
from django.urls import path
from snippets import views
urlpatterns = [
    path(‘snippets/‘, views.snippet_list),
    path(‘snippets/<int:pk>/‘, views.snippet_detail),
]
11.配置连接根tutorial/urls.py
from django.urls import path, include
urlpatterns = [
    path(‘‘, include(‘snippets.urls‘)),
]        
12.测试我们的api
    12.1: 手动导入两条数据
        from snippets.models import Snippet
        from snippets.serializers import SnippetSerializer
        from rest_framework.renderers import JSONRenderer
        from rest_framework.parsers import JSONParser
        snippet = Snippet(code=‘foo = "bar"\n‘)
        snippet.save()
        snippet = Snippet(code=‘print("hello, world")\n‘)
        snippet.save()
    12.2:测试
        pip install httpie  # 我们可以使用curl或httpie来测试我们的API。Httpie是一个用Python编写的用户友好的http客户机。让我们安装。
        python manage.py runserver
13.最后我们得到如下结果
Finally, we can get a list of all of the snippets:
浏览器中输入: http://127.0.0.1:8000/snippets/
    HTTP/1.1 200 OK
    ...
    [
      {
        "id": 1,
        "title": "",
        "code": "foo = \"bar\"\n",
        "linenos": false,
        "language": "python",
        "style": "friendly"
      },
      {
        "id": 2,
        "title": "",
        "code": "print(\"hello, world\")\n",
        "linenos": false,
        "language": "python",
        "style": "friendly"
      }
    ]
或者:we can get a particular snippet by referencing its id:
    http http://127.0.0.1:8000/snippets/2/
    HTTP/1.1 200 OK
    ...
    {
      "id": 2,
      "title": "",
      "code": "print(\"hello, world\")\n",
      "linenos": false,
      "language": "python",
      "style": "friendly"
    }
django-rest-framework(DRF)阅读笔记
原文:https://www.cnblogs.com/wgwblogs/p/10506364.html