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在django中使用redis及前后端分离直接使用原有login、logout

• 基本信息
• 修改django
• • 继承修改admin.py
  • 自定义app信息
  • 修改login
  • 修改logout
  • 修改session middleware

基本信息

环境	版本
python	3.7.12
django	3.1.12
django rest framework	3.12.4
django redis	5.0.0

修改django

继承修改admin.py

from bm_system.models import User
from django.contrib import admin
from django.apps import apps
from django import forms
from django.contrib.auth.forms import ReadOnlyPasswordHashField
from django.contrib.auth.admin import UserAdmin as BaseUserAdmin
from django.core.exceptions import ValidationError

# Register your models here.
# 自动注册所有model
models = apps.get_models()
for model in models:
    try:
        admin.site.register(model)
    except admin.sites.AlreadyRegistered:
        pass

# 修改user创建表单
class UserCreationForm(forms.ModelForm):
    password1 = forms.CharField(label='Password', widget=forms.PasswordInput)
    password2 = forms.CharField(label='Password confirmation', widget=forms.PasswordInput)

    class Meta:
        model = User
        fields = ('username', 'email', 'first_name', 'last_name')

    def clean_password2(self):
        # Check that the two password entries match
        password1 = self.cleaned_data.get("password1")
        password2 = self.cleaned_data.get("password2")
        if password1 and password2 and password1 != password2:
            raise ValidationError("Passwords don't match")
        return password2

    def save(self, commit=True):
        # Save the provided password in hashed format
        user = super().save(commit=False)
        user.set_password(self.cleaned_data["password1"])
        if commit:
            user.save()
        return user

# 修改user修改表单
class UserChangeForm(forms.ModelForm):
    """A form for updating users. Includes all the fields on
    the user, but replaces the password field with admin's
    disabled password hash display field.
    """
    password = ReadOnlyPasswordHashField()

    class Meta:
        model = User
        fields = ('username', 'email', 'password', 'first_name', 'last_name', 'is_active', 'is_superuser')

# 修改creatersuperuser命令显示表单信息
class UserAdmin(BaseUserAdmin):
    # The forms to add and change user instances
    form = UserChangeForm
    add_form = UserCreationForm

    # The fields to be used in displaying the User model.
    # These override the definitions on the base UserAdmin
    # that reference specific fields on auth.User.
    list_display = ('username', 'email', 'first_name', 'last_name', 'is_active', 'is_superuser')
    fieldsets = (
        (None, {'fields': ('username', 'email', 'password')}),
        ('Personal info', {'fields': ('first_name', 'last_name')}),
        ('Permissions', {'fields': ('is_active', 'is_superuser')}),
    )
    # add_fieldsets is not a standard ModelAdmin attribute. UserAdmin
    # overrides get_fieldsets to use this attribute when creating a user.
    add_fieldsets = (
        (None, {
            'classes': ('wide',),
            'fields': ('username', 'email', 'first_name', 'last_name', 'password1', 'password2'),
        }),
    )
    search_fields = ('email', 'username', 'first_name', 'last_name')
    ordering = ('email', 'username', 'first_name', 'last_name')
    filter_horizontal = ()

自定义app信息

# 根目录或app目录下均可
from django.apps import AppConfig
class BMSystemConfig(AppConfig):
    default_auto_field = 'django.db.models.BigAutoField'  # 修改表自增为BigAuto，默认Auto
    name = 'bm_system'  # 设定app name

# 在setting中INSTALLED_APPS中添加配置替换原有信息
INSTALLED_APPS = [
    'simpleui',
    'django_filters',
    'rest_framework',
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'bm_system.apps.BMSystemConfig',
    'corsheaders',
]

修改login

def login(request, user, backend=None):
    """
    Persist a user id and a backend in the request. This way a user doesn't
    have to reauthenticate on every request. Note that data set during
    the anonymous session is retained when the user logs in.
    """
    session_auth_hash = ''
    if user is None:
        user = request.user
    if hasattr(user, 'get_session_auth_hash'):
        session_auth_hash = user.get_session_auth_hash()
	# 查找现有请求中是否存在session信息，如果存在但信息和pk等信息不服则执行flush清除session，否则执行cycle_key新建或刷新session
    if SESSION_KEY in request.session:
    	
        if _get_user_session_key(request) != user.pk or (
                session_auth_hash and
                not constant_time_compare(request.session.get(HASH_SESSION_KEY, ''), session_auth_hash)):
            # To avoid reusing another user's session, create a new, empty
            # session if the existing session corresponds to a different
            # authenticated user.
            request.session.flush()
    else:
    	# 在使用redis时调用此步骤将通过调用django/contrib/sessions/backends/base.py中cycle_key方法进行redis存储
        request.session.cycle_key()
        # TODO 修改缓存存储内容
        # user_data = {'id': user.pk, 'username': user.username, 'email': user.email, 'is_active': user.is_active,
        #              'is_staff': user.is_staff, 'is_superuser': user.is_superuser}
        # request.session.cycle_key(user_data)

    try:
        backend = backend or user.backend
    except AttributeError:
        backends = _get_backends(return_tuples=True)
        if len(backends) == 1:
            _, backend = backends[0]
        else:
            raise ValueError(
                'You have multiple authentication backends configured and '
                'therefore must provide the `backend` argument or set the '
                '`backend` attribute on the user.'
            )
    else:
        if not isinstance(backend, str):
            raise TypeError('backend must be a dotted import path string (got %r).' % backend)

    request.session[SESSION_KEY] = user._meta.pk.value_to_string(user)
    request.session[BACKEND_SESSION_KEY] = backend
    request.session[HASH_SESSION_KEY] = session_auth_hash
    if hasattr(request, 'user'):
        request.user = user
    rotate_token(request)
    user_logged_in.send(sender=user.__class__, request=request, user=user)

# django/contrib/sessions/backends/base.py
    def cycle_key(self):
        """
        Create a new session key, while retaining the current session data.
        """
        data = self._session
        key = self.session_key
        # 此处因为setting中session设置使用cache，所以会调用django/contrib/sessions/backends/cache.py中create方法
        self.create()

        self._session_cache = data
        if key:
            self.delete(key)

# django/contrib/sessions/backends/cache.py

    def create(self):
        # Because a cache can fail silently (e.g. memcache), we don't know if
        # we are failing to create a new session because of a key collision or
        # because the cache is missing. So we try for a (large) number of times
        # and then raise an exception. That's the risk you shoulder if using
        # cache backing.
        for i in range(10000):
        	# 设置session
            self._session_key = self._get_new_session_key()
            try:
            	# 调用存储保存至redis
                self.save(must_create=True)

            except CreateError:
                continue
            self.modified = True
            return
        raise RuntimeError(
            "Unable to create a new session key. "
            "It is likely that the cache is unavailable.")

    def save(self, must_create=False):
        if self.session_key is None:
            return self.create()
        if must_create:
            func = self._cache.add
        # elif self._cache.get(self.cache_key) is not None:
        elif self._cache.get(self.session_key) is not None:
            func = self._cache.set
        else:
            raise UpdateError
        # 此处func就是调用django-redis中set或add方法进行存储session至redis中，原会在cache_key中添加cache_key_prefix前缀，未避免麻烦可以在cache_key中修改
        # self.cache_key为传入redis key
        # self._get_session(no_load=must_create)为传入redis value，非必要不建议修改此值，本身可通过此对象_auth_user_id进去user表中查找对应用户信息，若需修改最好使用内部调用然后追加或合并结果的方式，不然在admin管理页面使用时将无法使用
        # self.get_expiry_age())为传入redis TTL
        result = func(self.cache_key,
                      self._get_session(no_load=must_create),
                      self.get_expiry_age())
        if must_create and not result:
            raise CreateError

修改logout

def logout(request):
    """
    Remove the authenticated user's ID from the request and flush their session
    data.
    """
    # Dispatch the signal before the user is logged out so the receivers have a
    # chance to find out *who* logged out.
    # TODO 直接发送登出接口时添加Authorization检测
    # 为了使logout在前后端分离中也可使用，分别检测header authorization 及cookie
    authorization = request.META.get('HTTP_AUTHORIZATION')
    if authorization:
        token = authorization
        # 从Redis中取出token,前提是已经在settings中配置Redis
        _cache = caches[settings.SESSION_CACHE_ALIAS]
        user = _cache.get(token)
        if user:
            user = bm_system.models.User.objects.filter(pk=user['_auth_user_id'])
        else:
            user = None
        user_logged_out.send(sender=user.__class__, request=request, user=user)
        request.session.flush()
    else:
        user = getattr(request, 'user', None)
        if not getattr(user, 'is_authenticated', True):
            user = None
        user_logged_out.send(sender=user.__class__, request=request, user=user)
        request.session.flush()
    if hasattr(request, 'user'):
        from django.contrib.auth.models import AnonymousUser
        request.user = AnonymousUser()

修改session middleware

# django/contrib/sessions/middleware.py
    def process_response(self, request, response):
        """
        If request.session was modified, or if the configuration is to save the
        session every time, save the changes and set a session cookie or delete
        the session cookie if the session has been emptied.
        """
        try:
            accessed = request.session.accessed
            modified = request.session.modified
            empty = request.session.is_empty()
        except AttributeError:
            return response
        # First check if we need to delete this cookie.
        # The session should be deleted only if the session is entirely empty.
        # 有cookie但是显示session为空则会删除cookie
        if settings.SESSION_COOKIE_NAME in request.COOKIES and empty:
            response.delete_cookie(
                settings.SESSION_COOKIE_NAME,
                path=settings.SESSION_COOKIE_PATH,
                domain=settings.SESSION_COOKIE_DOMAIN,
                samesite=settings.SESSION_COOKIE_SAMESITE,
            )
            patch_vary_headers(response, ('Cookie',))
        else:
            if accessed:
                patch_vary_headers(response, ('Cookie',))
            if (modified or settings.SESSION_SAVE_EVERY_REQUEST) and not empty:
                if request.session.get_expire_at_browser_close():
                    max_age = None
                    expires = None
                else:
                    max_age = request.session.get_expiry_age()
                    expires_time = time.time() + max_age
                    expires = http_date(expires_time)
                # Save the session data and refresh the client cookie.
                # Skip session save for 500 responses, refs #3881.
                if response.status_code != 500:
                    try:
                    	# 每次session中间件均会检测刷新session，存储方式何在此处进行修改
                        request.session.save()
                        # TODO 修改缓存存储内容
                        # token = request.session.session_key
                        # _cache = caches[settings.SESSION_CACHE_ALIAS]
                        # user = _cache.get(token)
                        # request.session.save(user=user)
                    except UpdateError:
                        raise SuspiciousOperation(
                            "The request's session was deleted before the "
                            "request completed. The user may have logged "
                            "out in a concurrent request, for example."
                        )
                    response.set_cookie(
                        settings.SESSION_COOKIE_NAME,
                        request.session.session_key, max_age=max_age,
                        expires=expires, domain=settings.SESSION_COOKIE_DOMAIN,
                        path=settings.SESSION_COOKIE_PATH,
                        secure=settings.SESSION_COOKIE_SECURE or None,
                        httponly=settings.SESSION_COOKIE_HTTPONLY or None,
                        samesite=settings.SESSION_COOKIE_SAMESITE,
                    )
        return response