rest-framework框架——版本

from rest_framework import versioning           # view中引入版本控制
# 查看 rest_framework/versioning.py文件：

# 最基础的版本控制类，给其他版本控制类提供一些共用方法
class BaseVersioning:...

# 在accept请求头中配置版本信息
# accept代表希望返回的数据类型，可以携带版本信息
# Accept: application/json; version=1.0
class AcceptHeaderVersioning(BaseVersioning):   # 将版本信息放到请求头中
    """
    GET /something/ HTTP/1.1
    Host: example.com
    Accept: application/json; version=1.0
    """

# 在url上携带版本信息
# url(r‘^(?P<version>[v1|v2]+)/users/$‘, users_list, name=‘users-list‘),
class URLPathVersioning(BaseVersioning):        # 将版本信息放入URL中
    """
    To the client this is the same style as `NamespaceVersioning`.
    The difference is in the backend - this implementation uses
    Django‘s URL keyword arguments to determine the version.

    An example URL conf for two views that accept two different versions.

    urlpatterns = [
        url(r‘^(?P<version>[v1|v2]+)/users/$‘, users_list, name=‘users-list‘),
        url(r‘^(?P<version>[v1|v2]+)/users/(?P<pk>[0-9]+)/$‘, users_detail, name=‘users-detail‘)
    ]

    GET /1.0/something/ HTTP/1.1
    Host: example.com
    Accept: application/json
    """

# 把版本信息放在路由分发里，并把路由的namespace配置成版本
# url(r‘^v1/‘, include(‘users.urls‘, namespace=‘v1‘))
class NamespaceVersioning(BaseVersioning):      # 通过namespace来区分版本
    """
    To the client this is the same style as `URLPathVersioning`.
    The difference is in the backend - this implementation uses
    Django‘s URL namespaces to determine the version.

    An example URL conf that is namespaced into two separate versions

    # users/urls.py
    urlpatterns = [
        url(r‘^/users/$‘, users_list, name=‘users-list‘),
        url(r‘^/users/(?P<pk>[0-9]+)/$‘, users_detail, name=‘users-detail‘)
    ]

    # urls.py
    urlpatterns = [
        url(r‘^v1/‘, include(‘users.urls‘, namespace=‘v1‘)),
        url(r‘^v2/‘, include(‘users.urls‘, namespace=‘v2‘))
    ]

    GET /1.0/something/ HTTP/1.1
    Host: example.com
    Accept: application/json
    """

# 在我们的host上配置版本信息
# Host：v1.example.com
class HostNameVersioning(BaseVersioning):        # 通过主机名来区分版本
    """
    GET /something/ HTTP/1.1
    Host: v1.example.com
    Accept: application/json
    """

# 在url过滤条件上配置版本信息
# GET /something/?version=0.1 HTTP/1.1
class QueryParameterVersioning(BaseVersioning):  # 通过url查询参数区分版本
    """
    GET /something/?version=0.1 HTTP/1.1
    Host: example.com
    Accept: application/json
    """

class APIView(View):

    def dispatch(self, request, *args, **kwargs):
        self.args = args
        self.kwargs = kwargs
        # 此处做了一个封装
        request = self.initialize_request(request, *args, **kwargs)
        self.request = request
        self.headers = self.default_response_headers  # deprecate?

        try:
            self.initial(request, *args, **kwargs)

class APIView(View):

    def initial(self, request, *args, **kwargs):
        """
        Runs anything that needs to occur prior to calling the method handler.
        """
        self.format_kwarg = self.get_format_suffix(**kwargs)

        # Perform content negotiation and store the accepted info on the request
        neg = self.perform_content_negotiation(request)
        request.accepted_renderer, request.accepted_media_type = neg

        # Determine the API version, if versioning is in use.
        version, scheme = self.determine_version(request, *args, **kwargs)
        request.version, request.versioning_scheme = version, scheme
        ... 

api_settings = APISettings(None, DEFAULTS, IMPORT_STRINGS)

DEFAULTS = {
    ...
    ‘DEFAULT_VERSIONING_CLASS‘: None,
    ...
}

from rest_framework import versioning

# versionDemo/urls.py
from django.urls import path, include
from .views import DemoView

urlpatterns = [
    path(r"", DemoView.as_view()),
]


# versionDemo/views.py
from django.shortcuts import render
from rest_framework.views import APIView
from rest_framework.response import Response

class DemoView(APIView):
    def get(self, request):
        print(request.version)
        print(request.versioning_scheme)
        # 得到版本号，根据版本号的不同返回不同的信息

        if request.version == "v1":
            return Response("v1版本的数据")
        elif request.version == "v2":
            return Response("v2版本的数据")
        return Response("不存在的版本")

# 创建文件/DRFDemo/utils/version.py

class MyVersion:
    def determine_version(self, request, *args, **kwargs):
        # 该方法返回值给了 request.version
        # 返回版本号
        # 版本号携带在过滤条件中  xxx?version=v1
        version = request.query_params.get("version", "v1")
        return version 

REST_FRAMEWORK = {
    "DEFAULT_VERSIONING_CLASS": "utils.version.MyVersion"
}

from rest_framework.versioning import QueryParameterVersioning,AcceptHeaderVersioning,NamespaceVersioning,URLPathVersioning

#基于url的get传参方式：QueryParameterVersioning------>如：/users?version=v1
#基于url的正则方式：URLPathVersioning------>/v1/users/
#基于accept请求头方式：AcceptHeaderVersioning------>Accept: application/json; version=1.0
#基于主机名方法：HostNameVersioning------>v1.example.com
#基于django路由系统的namespace：NamespaceVersioning------>example.com/v1/users/

class BaseVersioning:
    default_version = api_settings.DEFAULT_VERSION     # 默认版本
    allowed_versions = api_settings.ALLOWED_VERSIONS   # 允许版本
    version_param = api_settings.VERSION_PARAM         # 关键字

    def determine_version(self, request, *args, **kwargs):
        msg = ‘{cls}.determine_version() must be implemented.‘
        raise NotImplementedError(msg.format(
            cls=self.__class__.__name__
        ))

    def reverse(self, viewname, args=None, kwargs=None, request=None, format=None, **extra):
        return _reverse(viewname, args, kwargs, request, format, **extra)

    def is_allowed_version(self, version):
        if not self.allowed_versions:
            return True
        return ((version is not None and version == self.default_version) or
                (version in self.allowed_versions))

REST_FRAMEWORK = {
    # "DEFAULT_VERSIONING_CLASS": "utils.version.MyVersion",
    # 默认使用的版本控制类
    "DEFAULT_VERSIONING_CLASS": "rest_framework.versioning.QueryParameterVersioning",
    # 默认使用的版本
    "DEFAULT_VERSION": "v1",
    # 允许的版本
    "ALLOWED_VERSIONS": "v1, v2",
    # 版本使用的参数名称
    "VERSION_PARAM": "ver"
}