用Python给二维码图片添加提示文字

# toolbox.py
from typing import Any
 
 
class UserAgent:
    def __init__(self, user_agent: str = '', request: Any = None):
        if request is not None:
            try:
                user_agent = request.headers.get('user-agent', '')  # For Sanic
            except AttributeError:
                user_agent = request.META.get('HTTP_USER_AGENT', '')  # Django
        self.user_agent = user_agent
 
    @property
    def is_alipay(self) -> bool:
        return "AlipayClient/" in self.user_agent
 
    @property
    def is_wechat(self) -> bool:
        return "MicroMessenger/" in self.user_agent
 
    @property
    def is_qq(self) -> bool:
        return " QQ/" in self.user_agent
 
    @property
    def scan_type(self) -> str:
        if self.is_wechat or self.is_qq:
            return "wechat"
        if self.is_alipay:
            return "alipay"
        return "unknown"

# image_text.py
"""
给图片（如二维码）添上文字
Usage::
    >>> from xxx import deco_image
    >>> deco_image(image_path, text)  # 替换旧图片
    >>> deco_image(image_path, text, new_path, color='red')  # 保留旧图片并指定文字颜色
"""
from pathlib import Path
from typing import Optional, Tuple, Union
 
from PIL import Image, ImageDraw, ImageFont  # pip install pillow
 
TIP = "请用微信扫码支付\n或分享到微信中打开"
 
 
# 获取图片宽度
def get_img_width(fname) -> int:
    return Image.open(fname).size[0]
 
 
# 获取图片高度
def get_img_height(fname) -> int:
    return Image.open(fname).size[1]
 
 
# 给图片加文字
# 生成blank_img空白图片，加上文字之后生成新图片或覆盖旧图, 宽度为origin_img原始图片的宽度
 
MARGIN_LEFT, MARGIN_TOP = 50, 15
FONT_SIZE = 22
FONT_COLOR = "red"
 
 
def gen_text_img(
    origin_img: Union[Path, str],
    text: str,
    img_path=None,
    color=FONT_COLOR,
    font_size: int = FONT_SIZE,
    margin_left: int = MARGIN_LEFT,
    margin_top: int = MARGIN_TOP,
    blank_img=None,
    font_path: Optional[str] = None,
    show_img: bool = False,
) -> Union[Path, str]:
    width = get_img_width(origin_img)
    if blank_img is None:
        blank_img = Path(f"/tmp/blank-{width}.png")
    elif isinstance(blank_img, str):
        blank_img = Path(blank_img)
    if not blank_img.exists():
        Image.new("RGB", (width, 70), (255, 255, 255)).save(blank_img)
    im = Image.open(blank_img)
    draw = ImageDraw.Draw(im)
    if font_path is None:
        # font_path = r"C:\Windows\Fonts\simsun.ttc"
        # font_path = "/System/Library/Fonts/Supplemental/Songti.ttc"
        font_path = "/usr/share/fonts/truetype/windows-font/Songti.ttc"
    fnt = ImageFont.truetype(font_path, font_size)
    draw.text((margin_left, margin_top), text, fill=color, font=fnt)
    if img_path is None:
        img_path = Path(origin_img)
        img_path = img_path.with_name(f"{img_path.stem}-{len(text)}{img_path.suffix}")
    im.save(img_path)
    if show_img:
        im.show()
    return img_path
 
 
# 拼接图片，把上面生成的文字图片拼接到原图上面
# 生成一张宽度一致，高度为两张图片之和的空白长图
# 分别打开图片进行粘贴到空白长图里面
 
def join_imgs(text_img, origin_img, new_path=None) -> None:
    w = get_img_width(text_img)
    fh = get_img_height(text_img)
    oh = get_img_height(origin_img)
 
    blank_long_img = Image.new("RGBA", (w, fh + oh))  # 空白长图
 
    font_img = Image.open(text_img).resize((w, fh), Image.ANTIALIAS)
    blank_long_img.paste(font_img, (0, 0))
 
    img1 = Image.open(origin_img).resize((w, oh), Image.ANTIALIAS)
    blank_long_img.paste(img1, (0, fh))
    if new_path is None:
        new_path = origin_img
    blank_long_img.save(new_path)
    blank_long_img.show()
 
 
def deco_image(
    fpath: Union[Path, str],  # 图片路径
    text: str = TIP,  # 要添加的文字
    new_path: Union[Path, str, None] = None,  # 新图片要保存的路径（默认覆盖原图）
    color: Union[str, Tuple[int, int, int]] = FONT_COLOR,  # 文字颜色
    font_size: int = FONT_SIZE,  # 文字高度
    margin_left: int = MARGIN_LEFT,
    margin_top: int = MARGIN_TOP,
) -> None:
    text_img = gen_text_img(
        fpath,
        text,
        color=color,
        font_size=font_size,
        margin_left=margin_left,
        margin_top=margin_top,
    )
    join_imgs(text_img, fpath)

sudo mkdir /usr/share/fonts/truetype/windows-font
sudo chmod 777 /usr/share/fonts/truetype/windows-font
cd /usr/share/fonts/truetype/windows-font
wget https://gitee.com/waketzheng/carstino/attach_files/703450/download/Songti.ttc  # 该文件比较大，有66.9MB

from pathlib import Path
from hashlib import md5
 
import qrcode  # pip install qrcode
from sanic import Blueprint
from sanic.log import logger
from sanic.request import Request
from sanic.response import json
 
from .models import Order
from .image_text import deco_image
from .toolbox import UserAgent
from .utils import async_http_post, get_host
from .consts import URL_PREFIX, WX_PAY_URL
 
 
bp = Blueprint("epay", url_prefix=URL_PREFIX)
 
async def get_qf_mch(community):
    pass
 
 
@bp.route("/pay-link", methods=["POST"])
async def pay_link(request: Request):
    requires, data = ["bills", "total", "next"], request.json
    logger.info(f"{request.url = } ;  {request.json = }")
    # 已经1分钟内生成过对应订单的，直接去支付
    content = request.body + f"{datetime.now():%y%m%d%H%M%S}".encode()
    body = md5(content).hexdigest()
    if not (order := await Order.filter(body=body).first()):
        order = await new_pay_order(origin, data, request, body)
    mchid, mch_name = await get_qf_mch(order.community)
    if mchid:
        host = get_host(request.headers)
        if not UserAgent(request=request).is_wechat:
            # 故判断当前是否在微信里，如果不是就直接生成二维码
            frontend_url = data["next"]
            fpath = "payit/" + md5(frontend_url.encode()).hexdigest() + ".png"
            if not (p := BASE_DIR / "media" / fpath).parent.exists():
                p.parent.mkdir(parents=True)
            qrcode.make(frontend_url).save(p)
            deco_image(p)
            img_url = host + URL_PREFIX + "/media/" + fpath
            return json({"payUrl": img_url})
        return json(qf_pay_it(mchid, mch_name, order, host=host))
    url = WX_PAY_URL
    if not (request_data := order.post_data).get("mch"):
        request_data.update(mch=1)  # 未配置支付的,先用1
    res = await async_http_post(url, request_data)
    try:
        res_json = res.json()
    except Exception as e:
        logger.error(f"{e = }; {url = }; {order.post_data=}; {res.content = }")
    return json(res_json)