from captcha.image import ImageCaptcha

# 創(chuàng)建驗(yàn)證碼圖像
image = ImageCaptcha(width=280, height=90)
data = image.generate('1234')
image.write('1234', 'out.png')

# settings.py
INSTALLED_APPS = [
    'captcha',
]

# models.py
from django import forms
from captcha.fields import CaptchaField

class ContactForm(forms.Form):
    captcha = CaptchaField()

# 安裝 captcha 庫（Flask/FastAPI 通用）
pip install captcha pillow

# 安裝 django-simple-captcha（Django 項(xiàng)目）
pip install django-simple-captcha

from flask import Flask, request, session, make_response
from captcha.image import ImageCaptcha
import random
import io

app = Flask(__name__)
app.secret_key = 'your-secret-key'

def generate_captcha():
    """生成驗(yàn)證碼"""
    # 生成隨機(jī)驗(yàn)證碼文本（排除易混淆字符）
    chars = 'ABCDEFGHJKLMNPQRSTUVWXYZ23456789'
    captcha_text = ''.join(random.choices(chars, k=4))
    
    # 創(chuàng)建驗(yàn)證碼圖像
    image = ImageCaptcha(width=120, height=40)
    data = image.generate(captcha_text)
    
    # 保存驗(yàn)證碼到 session
    session['captcha'] = captcha_text
    
    return data

@app.route('/captcha')
def get_captcha():
    """獲取驗(yàn)證碼圖片"""
    image_data = generate_captcha()
    
    response = make_response(image_data.getvalue())
    response.headers['Content-Type'] = 'image/png'
    # 防止緩存，確保每次請(qǐng)求都是新的驗(yàn)證碼
    response.headers['Cache-Control'] = 'no-cache, no-store, must-revalidate'
    response.headers['Pragma'] = 'no-cache'
    response.headers['Expires'] = '0'
    
    return response

@app.route('/verify', methods=['POST'])
def verify_captcha():
    """驗(yàn)證用戶輸入"""
    user_input = request.form.get('captcha', '').upper()
    server_captcha = session.get('captcha', '')
    
    if user_input == server_captcha:
        # 驗(yàn)證成功后清除驗(yàn)證碼，防止重復(fù)使用
        session.pop('captcha', None)
        return {'success': True, 'message': '驗(yàn)證碼正確'}
    else:
        return {'success': False, 'message': '驗(yàn)證碼錯(cuò)誤'}, 400

# settings.py
INSTALLED_APPS = [
    'captcha',
]

# 驗(yàn)證碼設(shè)置
CAPTCHA_LENGTH = 4  # 字符數(shù)
CAPTCHA_TIMEOUT = 5  # 過期時(shí)間（分鐘）
CAPTCHA_NOISE_FUNCTIONS = ('captcha.helpers.noise_null',)
CAPTCHA_IMAGE_SIZE = (120, 40)

# forms.py
from django import forms
from captcha.fields import CaptchaField

class LoginForm(forms.Form):
    username = forms.CharField()
    password = forms.CharField(widget=forms.PasswordInput)
    captcha = CaptchaField()

# views.py
from django.shortcuts import render
from .forms import LoginForm

def login_view(request):
    if request.method == 'POST':
        form = LoginForm(request.POST)
        if form.is_valid():
            # 驗(yàn)證通過，處理登錄邏輯
            username = form.cleaned_data['username']
            password = form.cleaned_data['password']
            # ... 登錄邏輯
    else:
        form = LoginForm()
    
    return render(request, 'login.html', {'form': form})

<!-- login.html -->
<form method="post">
    {% csrf_token %}
    {{ form.as_p }}
    <input type="submit" value="登錄">
</form>

from captcha.image import ImageCaptcha
from PIL import Image, ImageDraw, ImageFont, ImageFilter
import random
import string
import io

class AdvancedCaptcha:
    def __init__(self, width=160, height=60):
        self.width = width
        self.height = height
        self.font_size = 40
        
    def generate_text(self, length=4):
        """生成驗(yàn)證碼文本（排除易混淆字符）"""
        chars = string.ascii_uppercase + string.digits
        exclude_chars = {'0', 'O', '1', 'I', 'L'}
        chars = [c for c in chars if c not in exclude_chars]
        return ''.join(random.choices(chars, k=length))
    
    def create_image(self, text):
        """創(chuàng)建驗(yàn)證碼圖像（添加干擾）"""
        # 創(chuàng)建畫布
        image = Image.new('RGB', (self.width, self.height), (255, 255, 255))
        draw = ImageDraw.Draw(image)
        
        # 添加隨機(jī)干擾點(diǎn)
        for _ in range(200):
            x = random.randint(0, self.width)
            y = random.randint(0, self.height)
            draw.point((x, y), fill=self._random_color(150, 250))
        
        # 添加隨機(jī)干擾線
        for _ in range(5):
            x1 = random.randint(0, self.width)
            y1 = random.randint(0, self.height)
            x2 = random.randint(0, self.width)
            y2 = random.randint(0, self.height)
            draw.line([(x1, y1), (x2, y2)], fill=self._random_color(100, 200), width=1)
        
        # 繪制文字
        try:
            font = ImageFont.truetype('arial.ttf', self.font_size)
        except:
            font = ImageFont.load_default()
        
        # 文字扭曲效果
        for i, char in enumerate(text):
            # 每個(gè)字符隨機(jī)偏移
            x = 20 + i * 35 + random.randint(-5, 5)
            y = 5 + random.randint(-5, 5)
            draw.text((x, y), char, font=font, fill=self._random_color(20, 120))
        
        # 添加濾鏡效果
        image = image.filter(ImageFilter.SMOOTH_MORE)
        
        # 轉(zhuǎn)換為字節(jié)流
        img_byte_arr = io.BytesIO()
        image.save(img_byte_arr, format='PNG')
        img_byte_arr = img_byte_arr.getvalue()
        
        return img_byte_arr, text
    
    def _random_color(self, low, high):
        """生成隨機(jī)顏色"""
        return (random.randint(low, high), 
                random.randint(low, high), 
                random.randint(low, high))

import time
from flask import session

def set_captcha_session(text):
    session['captcha'] = text
    session['captcha_time'] = time.time()

def verify_captcha_with_timeout(user_input, timeout=300):  # 5分鐘過期
    if 'captcha' not in session or 'captcha_time' not in session:
        return False
    
    if time.time() - session['captcha_time'] > timeout:
        # 清理過期驗(yàn)證碼
        session.pop('captcha', None)
        session.pop('captcha_time', None)
        return False
    
    return user_input.upper() == session['captcha'].upper()

<!-- HTML前端代碼 -->
<form id="login-form">
    <input type="text" name="username" placeholder="用戶名">
    <input type="password" name="password" placeholder="密碼">
    <div>
        <input type="text" name="captcha" placeholder="驗(yàn)證碼">
        <img id="captcha-img" src="/captcha" 
             onclick="this.src='/captcha?'+Date.now()" 
             style="cursor:pointer; vertical-align:middle;">
        <a href="javascript:;" rel="external nofollow"  rel="external nofollow"  onclick="refreshCaptcha()">換一張</a>
    </div>
    <button type="submit">登錄</button>
</form>

<script>
function refreshCaptcha() {
    // 通過添加時(shí)間戳參數(shù)強(qiáng)制刷新
    document.getElementById('captcha-img').src = '/captcha?' + Date.now();
}
</script>

from flask import request
from functools import wraps
import time

# 簡(jiǎn)單的內(nèi)存緩存（生產(chǎn)環(huán)境建議用 Redis）
request_cache = {}

def rate_limit(max_requests=5, window=60):
    def decorator(f):
        @wraps(f)
        def wrapper(*args, **kwargs):
            ip = request.remote_addr
            now = time.time()
            
            if ip in request_cache:
                requests = [r for r in request_cache[ip] if now - r < window]
                if len(requests) >= max_requests:
                    return {'error': '請(qǐng)求過于頻繁'}, 429
                requests.append(now)
                request_cache[ip] = requests
            else:
                request_cache[ip] = [now]
            
            return f(*args, **kwargs)
        return wrapper
    return decorator

@app.route('/captcha')
@rate_limit(max_requests=5, window=60)
def get_captcha():
    # ... 生成驗(yàn)證碼

import base64

@app.route('/api/captcha')
def get_captcha_api():
    image_data, text = generate_captcha()
    base64_data = base64.b64encode(image_data.getvalue()).decode()
    
    # 保存驗(yàn)證碼到 session 或 Redis
    session['captcha'] = text
    
    return {
        'image': f'data:image/png;base64,{base64_data}',
        'expires_in': 300  # 過期時(shí)間（秒）
    }

# 使用 captcha 庫，簡(jiǎn)單快速
from captcha.image import ImageCaptcha
from flask import Flask, session, make_response

app = Flask(__name__)
app.secret_key = 'your-secret-key'

@app.route('/captcha')
def get_captcha():
    image = ImageCaptcha(width=120, height=40)
    captcha_text = ''.join(random.choices('0123456789', k=4))
    data = image.generate(captcha_text)
    session['captcha'] = captcha_text
    response = make_response(data.getvalue())
    response.headers['Content-Type'] = 'image/png'
    return response

# 使用更復(fù)雜的驗(yàn)證碼，但不要太難
class LoginCaptcha:
    def generate(self):
        # 使用字母+數(shù)字，排除易混淆字符
        chars = 'ABCDEFGHJKLMNPQRSTUVWXYZ23456789'
        captcha_text = ''.join(random.choices(chars, k=4))
        # 生成帶干擾的驗(yàn)證碼圖片
        # ...

@app.route('/api/captcha')
def get_captcha_api():
    image_data, text = generate_captcha()
    base64_data = base64.b64encode(image_data).decode()
    
    # 保存到 Redis（推薦）或 session
    redis_client.setex(f'captcha:{session_id}', 300, text)
    
    return {
        'image': f'data:image/png;base64,{base64_data}',
        'expires_in': 300
    }

# 最小化實(shí)現(xiàn)
pip install captcha pillow

# 生成驗(yàn)證碼
from captcha.image import ImageCaptcha

image = ImageCaptcha()
data = image.generate('1234')
with open('captcha.png', 'wb') as f:
    f.write(data.getvalue())

from flask import Flask, request, session, make_response, render_template_string
from captcha.image import ImageCaptcha
import random
import time
import io

app = Flask(__name__)
app.secret_key = 'your-secret-key-change-in-production'

# HTML 模板
HTML_TEMPLATE = """
<!DOCTYPE html>
<html>
<head>
    <title>驗(yàn)證碼示例</title>
    <style>
        body {
            font-family: Arial, sans-serif;
            max-width: 500px;
            margin: 50px auto;
            padding: 20px;
        }
        .form-group {
            margin-bottom: 15px;
        }
        label {
            display: block;
            margin-bottom: 5px;
        }
        input[type="text"], input[type="password"] {
            width: 100%;
            padding: 8px;
            box-sizing: border-box;
        }
        .captcha-group {
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .captcha-img {
            cursor: pointer;
            border: 1px solid #ddd;
            padding: 5px;
        }
        .refresh-link {
            color: #007bff;
            text-decoration: none;
        }
        .refresh-link:hover {
            text-decoration: underline;
        }
        button {
            background-color: #007bff;
            color: white;
            padding: 10px 20px;
            border: none;
            cursor: pointer;
        }
        .message {
            margin-top: 10px;
            padding: 10px;
            border-radius: 4px;
        }
        .success {
            background-color: #d4edda;
            color: #155724;
        }
        .error {
            background-color: #f8d7da;
            color: #721c24;
        }
    </style>
</head>
<body>
    <h2>登錄示例</h2>
    <form method="POST" action="/login">
        <div class="form-group">
            <label>用戶名：</label>
            <input type="text" name="username" required>
        </div>
        <div class="form-group">
            <label>密碼：</label>
            <input type="password" name="password" required>
        </div>
        <div class="form-group">
            <label>驗(yàn)證碼：</label>
            <div class="captcha-group">
                <input type="text" name="captcha" required style="flex: 1;">
                <img id="captcha-img" class="captcha-img" 
                     src="/captcha" 
                     onclick="refreshCaptcha()" 
                     alt="驗(yàn)證碼">
                <a href="javascript:;" rel="external nofollow"  rel="external nofollow"  onclick="refreshCaptcha()" class="refresh-link">換一張</a>
            </div>
        </div>
        <button type="submit">登錄</button>
    </form>
    
    {% if message %}
    <div class="message {{ message_type }}">
        {{ message }}
    </div>
    {% endif %}
    
    <script>
        function refreshCaptcha() {
            document.getElementById('captcha-img').src = '/captcha?' + Date.now();
        }
    </script>
</body>
</html>
"""

def generate_captcha_text(length=4):
    """生成驗(yàn)證碼文本（排除易混淆字符）"""
    chars = 'ABCDEFGHJKLMNPQRSTUVWXYZ23456789'
    return ''.join(random.choices(chars, k=length))

def generate_captcha():
    """生成驗(yàn)證碼圖片"""
    captcha_text = generate_captcha_text()
    
    # 創(chuàng)建驗(yàn)證碼圖像
    image = ImageCaptcha(width=120, height=40)
    data = image.generate(captcha_text)
    
    # 保存驗(yàn)證碼到 session（帶時(shí)間戳）
    session['captcha'] = captcha_text
    session['captcha_time'] = time.time()
    
    return data

@app.route('/')
def index():
    """首頁"""
    return render_template_string(HTML_TEMPLATE)

@app.route('/captcha')
def get_captcha():
    """獲取驗(yàn)證碼圖片"""
    image_data = generate_captcha()
    
    response = make_response(image_data.getvalue())
    response.headers['Content-Type'] = 'image/png'
    # 防止緩存
    response.headers['Cache-Control'] = 'no-cache, no-store, must-revalidate'
    response.headers['Pragma'] = 'no-cache'
    response.headers['Expires'] = '0'
    
    return response

def verify_captcha(user_input, timeout=300):
    """驗(yàn)證驗(yàn)證碼（帶過期時(shí)間）"""
    if 'captcha' not in session or 'captcha_time' not in session:
        return False, '驗(yàn)證碼已過期，請(qǐng)刷新'
    
    # 檢查是否過期（5分鐘）
    if time.time() - session['captcha_time'] > timeout:
        session.pop('captcha', None)
        session.pop('captcha_time', None)
        return False, '驗(yàn)證碼已過期，請(qǐng)刷新'
    
    # 驗(yàn)證（忽略大小寫）
    if user_input.upper() != session['captcha'].upper():
        return False, '驗(yàn)證碼錯(cuò)誤'
    
    # 驗(yàn)證成功后清除驗(yàn)證碼（一次性使用）
    session.pop('captcha', None)
    session.pop('captcha_time', None)
    
    return True, '驗(yàn)證成功'

@app.route('/login', methods=['GET', 'POST'])
def login():
    """登錄處理"""
    if request.method == 'POST':
        username = request.form.get('username', '')
        password = request.form.get('password', '')
        captcha_input = request.form.get('captcha', '')
        
        # 驗(yàn)證驗(yàn)證碼
        is_valid, message = verify_captcha(captcha_input)
        
        if not is_valid:
            return render_template_string(
                HTML_TEMPLATE,
                message=message,
                message_type='error'
            )
        
        # 這里處理實(shí)際的登錄邏輯
        # 示例：簡(jiǎn)單的用戶名密碼驗(yàn)證
        if username == 'admin' and password == '123456':
            return render_template_string(
                HTML_TEMPLATE,
                message='登錄成功！',
                message_type='success'
            )
        else:
            return render_template_string(
                HTML_TEMPLATE,
                message='用戶名或密碼錯(cuò)誤',
                message_type='error'
            )
    
    return render_template_string(HTML_TEMPLATE)

if __name__ == '__main__':
    app.run(debug=True)

pip install flask captcha pillow

python app.py