1.目的
现在我们一般访问网页都需要输入验证码，比如博客园，有的甚至是通过手机验证码实时登录。这样做的目的主要还是为了防止其他人的恶意访问，比如爬虫，下面就来看看验证码是如何实现的
2.演示
这里我在项目下创建了一个utils文件，存放验证码文件，字体文件下载猛戳这里
utils/code.py
import random
from PIL import Image,ImageDraw,ImageFont,ImageFilter
def check_code(width=120, height=30, char_length=5, font_file=‘kumo.ttf‘, font_size=28):
"""
生成一个120*30验证码框体，28字体，字体文件需自己导入
char_length代表生成5个字母
:return:
"""
code = [] # 用于存放每个验证码
img = Image.new(mode=‘RGB‘, size=(width, height), color=(255, 255, 255))
draw = ImageDraw.Draw(img, mode=‘RGB‘)
def rndChar():
"""
生成随机字母A-Z
:return:
"""
return chr(random.randint(65, 90))
def rndColor():
"""
生成随机颜色
:return:
"""
return (random.randint(0, 255), random.randint(10, 255), random.randint(64, 255))
# 写文字
font = ImageFont.truetype(font_file, font_size)
for i in range(char_length):
char = rndChar()
code.append(char) # 循环了char_length次并追加进去
h = random.randint(0, 4)
draw.text([i * width / char_length, h], char, font=font, fill=rndColor())
# 写干扰点
for i in range(40):
draw.point([random.randint(0, width), random.randint(0, height)], fill=rndColor())
# 写干扰圆圈
for i in range(40):
draw.point([random.randint(0, width), random.randint(0, height)], fill=rndColor())
x = random.randint(0, width)
y = random.randint(0, height)
draw.arc((x, y, x + 4, y + 4), 0, 90, fill=rndColor())
# 画干扰线
for i in range(5):
x1 = random.randint(0, width)
y1 = random.randint(0, height)
x2 = random.randint(0, width)
y2 = random.randint(0, height)
draw.line((x1, y1, x2, y2), fill=rndColor())
img = img.filter(ImageFilter.EDGE_ENHANCE_MORE)
return img, ‘‘.join(code)
views.py
from django.shortcuts import render,HttpResponse,redirect
from django.contrib import auth
# 从utils文件夹下的code文件导入 check_code
from utils.code import check_code
def code(request):
"""
生成图片验证码
"""
img,random_code = check_code()
request.session[‘random_code‘] = random_code
from io import BytesIO
# 实现了在内存中操作bytes
stream = BytesIO()
# 将二维码最终转为png格式
img.save(stream, ‘png‘)
return HttpResponse(stream.getvalue())
def login(request):
"""
用户登陆
"""
if request.method == ‘GET‘:
return render(request,‘login.html‘)
user = request.POST.get(‘user‘)
pwd = request.POST.get(‘pwd‘)
code = request.POST.get(‘code‘)
if code.upper() != request.session[‘random_code‘].upper():
return render(request,‘login.html‘,{‘msg‘:‘验证码错误‘})
# 通过auth模块进行用户认证
user = auth.authenticate(username=user,password=pwd)
if user:
return redirect(‘https://www.luffycity.com‘)
return render(request, ‘login.html‘, {‘msg‘: ‘用户名或密码错误‘})
login.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<form method="post">
{% csrf_token %}
<p>
<input type="text" name="user" placeholder="用户名" />
</p>
<p>
<input type="password" name="pwd" placeholder="密码" />
</p>
<p>
<input type="text" name="code" placeholder="验证" />
<img onclick="changeImg(this);" src="/code/" title="点击更换">
</p>
<input type="submit" value="提交">{{ msg }}
</form>
<script>
// 通过changeImg事件来更换图片
function changeImg(ths) {
ths.src = ths.src + ‘?‘;
console.log(ths.src);
}
</script>
</body>
</html>
# 这里对于changeImg事件加问号还不是太明白
# 对于这里是如何利用random模块实现验证码功能的，详细内容可以参考这里
原文地址：https://www.cnblogs.com/LearningOnline/p/9346270.html
时间： 2024-08-23 07:36:27