list safe 到你 .get 得到 html 方法 url include

1.安裝：
pip install django
pip install djangorestframework
pip install pygments # 此模塊用來使得代碼可以突出顯示

2。創建一個新的環境：

virtualenv env
source env/bin/activate

3.創建工程：
cd # cd 到你要創建工程的目錄

django-admin startproject tutorial

cd tutorial

python manage.py startapp snippets # 創建webapi
4.配置：
在settings.py的INSTALLED_APPS中配置：

INSTALLED_APPS = (
...
‘rest_framework‘,
‘snippets.apps.SnippetsConfig‘,
)

5.編輯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.初始化和遷移數據庫

python manage.py makemigrations snippets
python manage.py migrate

7.創建序列化的類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使得上面的代碼更加簡潔

class SnippetSerializer(serializers.ModelSerializer):
class Meta:
model = Snippet
fields = (‘id‘, ‘title‘, ‘code‘, ‘linenos‘, ‘language‘, ‘style‘)
"""
重要的是要記住，ModelSerializer類並沒有什麽特別神奇的功能，它們只是創建序列化器類的快捷方式:
一組自動確定的字段。
create()和update()方法的簡單默認實現。
"""

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)

"""
值得註意的是，有幾個邊緣情況我們目前沒有正確處理。如果我們發送格式不正確的json，
或者使用視圖無法處理的方法發出請求，那麽我們將得到500個“服務器錯誤”響應。
不過，現在這樣就可以了。
"""
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.配置連接根tutorial/urls.py

from django.urls import path, include

urlpatterns = [
path(‘‘, include(‘snippets.urls‘)),
]

12.測試我們的api
12.1: 手動導入兩條數據
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：測試
pip install httpie # 我們可以使用curl或httpie來測試我們的API。Httpie是一個用Python編寫的用戶友好的http客戶機。讓我們安裝。
python manage.py runserver

13.最後我們得到如下結果

Finally, we can get a list of all of the snippets:

瀏覽器中輸入： 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)閱讀筆記