Python生成图形验证码

1.安装依赖

pip install Pillow

2.生成验证码

# validCode.py

import os
import random
from PIL import Image
from PIL import ImageDraw
from PIL import ImageFont


def random_str():
    '''
    获取一个随机字符, 数字或小写字母
    :return:
    '''
    random_num = str(random.randint(1, 9))
    random_low_alpha = chr(random.randint(97, 122))
    while random_low_alpha in ['i', 'o', 'l']:  # 移除i o l不易识别验证码
        random_low_alpha = chr(random.randint(97, 122))
    random_char = random.choice([random_num, random_low_alpha])
    return random_char


def random_color():
    '''
    验证码字体颜色
    '''
    c1 = random.randint(0, 255)
    c2 = random.randint(0, 255)
    c3 = random.randint(0, 255)
    return c1, c2, c3


def generate_picture(width=120, height=35):
    '''
    生成验证码图片
    '''
    image = Image.new('RGB', (width, height), random_color())
    return image


def draw_str(count, image, font_size):
    '''
    在图片上写随机字符
    :param count: 字符数量
    :param image: 图片对象
    :param font_size: 字体大小
    :return:
    '''
    draw = ImageDraw.Draw(image)
    # 获取一个font字体对象参数是ttf的字体文件的目录，以及字体的大小
    font_file = os.path.join('arial.ttf')
    font = ImageFont.truetype(font_file, size=font_size)
    temp = []
    for i in range(count):
        random_char = random_str()
        draw.text((10 + i * 30, -2), random_char, random_color(), font=font)
        temp.append(random_char)

    valid_str = ''.join(temp)  # 验证码
    return valid_str, image


def noise(image, width=120, height=35, line_count=3, point_count=20):
    '''
    生成图片干扰信息
    :param image: 图片对象
    :param width: 图片宽度
    :param height: 图片高度
    :param line_count: 线条数量
    :param point_count: 点的数量
    :return:
    '''
    draw = ImageDraw.Draw(image)
    for i in range(line_count):
        x1 = random.randint(0, width)
        x2 = random.randint(0, width)
        y1 = random.randint(0, height)
        y2 = random.randint(0, height)
        draw.line((x1, y1, x2, y2), fill=random_color())

        # 画点
        for i in range(point_count):
            draw.point([random.randint(0, width), random.randint(0, height)], fill=random_color())
            x = random.randint(0, width)
            y = random.randint(0, height)
            draw.arc((x, y, x + 4, y + 4), 0, 90, fill=random_color())

    return image


def generate_code():
    '''
    生成验证码
    :return:str code
    '''
    image = generate_picture()
    valid_str, image = draw_str(4, image, 35)
    image = noise(image)

    return valid_str, image

3.接口返回

from io import BytesIO
from flask import session, send_file
from app import app # app为Falsk(__name__)实例
from app.common.utils import getNow
from app.common.validCode import generate_code


# 获取图形验证码
@app.route('/api/auth/graphicCode', methods=['get'])
def graphicCode():
    try:
        # 生成验证码
        code, image = generate_code()

        # 设置session验证码，配合登录
        session['GraphicCode'] = {"code": code, "time": getNow()}

        # 将图像保存到字节流中
        image_stream = BytesIO()
        image.save(image_stream, 'PNG')
        image_stream.seek(0)

        # 返回图像给用户
        return send_file(image_stream, mimetype='image/png')
    except Exception as e:
        return failure(msg=e.error)