爬虫实战国家企业公示网-webapi实现

Posted 2021-09-13 ZSYL

webapi代码实现

• 1. quart框架
• • 1.1 介绍
  • 1.2 安装
  • 1.3 文档
• 2. 代码实现
• • 2.1 webapi.py
  • 2.2 static.py

学习目标：

1. 了解 quart框架
2. 了解 各个接口的功能

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1. quart框架

1.1 介绍

1. quart是基于Asyncio的Python微框架。它志在让开发者能够在Web开发中很容易地得到Asyncio带来的好处。它对Flask应用的支持最好，它和Flask拥有相同的API
2. 支持 HTTP/1.1，HTTP/2 和 Websockets
3. 扩展性很强，并支持很多Flask的扩展

1.2 安装

pip install quart

1.3 文档

https://gitlab.com/pgjones/quart/

2. 代码实现

2.1 webapi.py

/gsxt/webapi.py

# THE WINTER IS COMING! the old driver will be driving who was a man of the world!
# -*- coding: utf-8 -*- python 3.6.7, create time is 18-11-9 下午7:27 GMT+8

import os
from uuid import uuid1
from base64 import b64encode
from redis import StrictRedis
from quart import (
    Quart,
    make_response,
    request,
    jsonify,
)

import static


redis = StrictRedis(decode_responses=True)
app = Quart(__name__)
app.config['JSON_AS_ASCII'] = False # 让jsonify()返回的json数据以utf8编码方式正常显示中文


@app.route('/', methods=['GET'])
async def index():
    """首页 接口说明"""
    headers = {"Content-type": "text/plain; charset=UTF-8"}
    resp = make_response((static.__doc__, 200, headers))
    return await resp

@app.route('/company', methods=['GET'])
async def company():
    """接收任务参数,写入redis"""
    company_name = request.args.get('company_name', None)
    if company_name is None:
        return jsonify({'status': 'failed', 'msg': '/company?company_name=缺少公司名称参数'})
    token = uuid1()
    # token = 'captcha_img' # 简单测试用
    gsxt_task_json = {
        'company_name': company_name,
        'crack_captcha_mode': request.args.get('crack_captcha_mode', None) or '0',
        'token': token,
        'status': 'wait',
        'msg': '新任务等待抓取'
    }
    try: # 向redis推任务
        task_key = '{}:{}'.format(static.GSXT_TASK_TOPIC, token)
        redis.hmset(task_key, gsxt_task_json)
        redis.expire(task_key, 600) # 过期时间
        redis.rpush(static.GSXT_TOKEN, token)
        redis.expire(static.GSXT_TOKEN, 590)
    except:
        gsxt_task_json['msg'] = '接收任务失败,检查redis及配置'
        return jsonify(gsxt_task_json)
    gsxt_task_json['msg'] = '成功接收抓取任务'
    return jsonify(gsxt_task_json)


@app.route('/crack_captcha', methods=['GET', 'POST'])
async def crack_captcha():
    """GET: 返回手动打码的html
    POST: 接收手动输入的验证码信息"""
    if request.method == 'GET':
        token = request.args.get('token', None)
        if token is None:
            return jsonify({'status': 'failed', 'msg': '/crack_captcha?token=缺少token参数'})
        img_file_path = './images/{}.jpg'.format(token) # 图片路径:以token命名图片
        # try:
        with open(img_file_path, 'rb') as f:
            img_b64_str = b64encode(f.read()).decode() # 为了前端渲染展示:图片二进制字节流转base64字符串
        # format(IMG_BASE64, CRACK_CAPTCHA_URL, TOKEN)
        return static.img_html%{'IMG_BASE64':img_b64_str,
                                'CRACK_CAPTCHA_URL':'/crack_captcha',
                                'TOKEN':token}
        # except:
        #     return jsonify({'status': 'failed', 'msg': '没有名为{}.jpg的图片,稍后重试或检查任务是否存在'.format(token)})

    elif request.method == 'POST':
        form_data = await request.form
        captcha_params = form_data.get('captcha_params', None)
        # print(captcha_params)
        token = form_data.get('token', None)
        # 将验证坐标存入redis
        task_key = '{}:{}'.format(static.GSXT_TASK_TOPIC, token)
        redis.hset(task_key, 'captcha_params', captcha_params)
        # os.remove('./images/{}.jpg'.format(token)) # 删除图片
        return jsonify({'token': token,
                        'result_url': '/result?token={}'.format(token),})


@app.route('/result')
async def result():
    """查询任务结果"""
    token = request.args.get('token', None)
    if token is None:
        return jsonify({'status': 'failed', 'msg': '/crack_captcha?token=缺少token参数'})
    task_key = '{}:{}'.format(static.GSXT_TASK_TOPIC, token)
    result_dict = redis.hgetall(task_key)
    return jsonify(result_dict)


if __name__ == '__main__':

    app.run()

2.2 static.py

/gsxt/static.py

"""
国家企业公示网实时数据抓取demo组件说明


webapi.py 交互演示功能
    任务参数push到redis消息总线中,
    数据查询也从redis消息总线中获取

    GET /
    接口说明文档

    GET /company
    接收任务参数
    params json = {
        company_name: 公司名称,
        crack_captcha_mode: 默认'0'(手动破解); '1'为调用打码平台破解,
    }
    return json = {
        company_name: 公司名称,
        token: 任务唯一识别码,
        crack_captcha_url: 手动破解验证的url,
    }

    GET /crack_captcha
    获取验证图片并返回手动破解验证码的html
    params json = {
        token: 任务唯一识别码,
    }
    return image in HTML

    POST /crack_captcha
    接收手动输入的验证码信息
    params json = {
        token: 任务唯一识别码,
        captcha_params: 验证码所需参数,
    }
    return json = {
        token: 任务唯一识别码,
        result_url: 查询抓取结果的url,
    }

    GET /result
    params json = {
        token: 任务唯一识别码,
    }

    return gsxt_task:token


redis 消息总线及缓存
    gsxt_token = [token1, token2, ...]

    gsxt_task:token
        {
            company_name,
            crack_captcha_mode,
            captcha_params,
            status, # 'wait', 任务没开始
                    # 'crawling', 抓取中
                    # 'failed', 失败
                    # 'done', 完成
            msg,
            data,
        }

crawler.py
    轮询redis
    抓取数据

static.py
    静态变量
    配置文件
"""

img_html = """<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>spider_gsxt</title>
</head>
<body>
    <div>
        <img id="imgPIC" src="data:image/jpg;base64,%(IMG_BASE64)s" alt="" οnclick="Show(this)">
    </div>
    <div>
        X:<input id="xxx" type="text" />
        Y:<input id="yyy" type="text" />
        <h3>按顺序依次点击图中的字符,并点击提交</h3>
        <form action="%(CRACK_CAPTCHA_URL)s" method="post">
            <input type="text" id="captcha_params" name="captcha_params">
            <input type="hidden" value="%(TOKEN)s" name="token">
            <input type="submit" value="提交">
        </form>
    </div>
</body>
<script language="javascript">
    function mousePosition(ev){
        if(ev.pageX || ev.pageY){
            return {x:ev.pageX, y:ev.pageY};
          }
        return {
            x:ev.clientX + document.body.scrollLeft - document.body.clientLeft,
            y:ev.clientY + document.body.scrollTop  - document.body.clientTop
        };
    }
    function mouseMove(ev){
        ev = ev || window.event;
        var mousePos = mousePosition(ev);
        document.getElementById('xxx').value = mousePos.x;
        document.getElementById('yyy').value = mousePos.y;
    }
    document.onmousemove = mouseMove;
    function Show(el){
        var x = parseInt(document.getElementById('xxx').value)-el.offsetLeft;
        var y = parseInt(document.getElementById('yyy').value)-el.offsetTop;
        var captcha_params = document.getElementById('captcha_params').value;
        document.getElementById('captcha_params').value = captcha_params + x + "," + y + ",";
    }
</script>
<style>
    body{
        margin: 0;
        padding: 0;
    }
</style>
</html>"""

# 配置
GSXT_TOKEN = 'gsxt_token'
GSXT_TASK_TOPIC = 'gsxt_task'

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小结

1. 了解 quart框架
2. 了解 各个接口的功能