Django 使用图形验证码

相关模块

django-simple-captcha

pip install django-simple-captcha

配置URL

先将captcha添加到url中

urlpatterns = [
    path('captcha/', include('captcha.urls')),
]

该模块是如何生成图形验证码的

在生成图形验证码时，会先生成图形验证码上显示的字符challenge、正确的答案response、用来唯一表示图形验证码的hashkey、以及过期时间expiration，然后将这些数据存入数据库

class CaptchaStore(models.Model):
    id = models.AutoField(primary_key=True)
    challenge = models.CharField(blank=False, max_length=32)
    response = models.CharField(blank=False, max_length=32)
    hashkey = models.CharField(blank=False, max_length=40, unique=True)
    expiration = models.DateTimeField(blank=False)

然后根据challenge的值生成图片，返回给客户端

常用方法

from captcha.models import CaptchaStore

生成图形验证码

CaptchaStore.generate_key()

CaptchaStore.pick()

移除数据库中存储的过期的验证码

CaptchaStore.remove_expired()

验证图形验证码

def check_captcha(captcha_hashkey, captcha_response):
    CaptchaStore.remove_expired()
    try:
        store = CaptchaStore.objects.get(hashkey=key)
    except CaptchaStore.DoesNotExist:
        # HTTP 410 Gone status so that crawlers don't index these expired urls.
        return HttpResponse(status=410)
    return captcha_response == store.response

获取图形验证码URL

from captcha.helpers import captcha_image_url
captcha_url = captcha_image_url(hashkey)

全局配置项

https://django-simple-captcha.readthedocs.io/en/latest/advanced.html

CaptchaStore.generate_key

generator用来表示生成图形验证码的函数，默认是配置项CAPTCHA_CHALLENGE_FUNCT指定的函数（captcha.helpers.random_char_challenge）。

challenge表示图形验证码中显示的内容，response表示正确的答案

def generate_key(cls, generator=None):
    challenge, response = captcha_settings.get_challenge(generator)()
    store = cls.objects.create(challenge=challenge, response=response)
    return store.hashkey

相关文档

https://pypi.org/project/django-simple-captcha/
http://django-simple-captcha.readthedocs.org/en/latest/