【测试】selenium拦截Ajax（XHR）等异步请求数据

本文介绍: 在爬取某个网站的时候遇到加密参数，由于js 代码经过混淆编译不好破解，所以采用selenium的方式获取参数，但是我们获取 selenium的数据基本上都是基于页面的，对于网站发起的异步请求，我们可以从日志中提取。显式等待的方式等待某个元素出现，你也可以隐式等待或者直接sleep，如果你不等待，异步请求还没加载完就开始获取，你可能会拿不到想要的数据。的日志，即发送异步请求的数据，因为我需要该请求的请求头，如果是响应类型的日志（方法获取对应的日志，之后再过滤出自己想要的日志就行。字段是没有响应体的，你需要通过。

1.说明

在爬取某个网站的时候遇到加密参数，由于js 代码经过混淆编译不好破解，所以采用selenium的方式获取参数，但是我们获取selenium的数据基本上都是基于页面的，对于网站发起的异步请求，我们可以从日志中提取

2.设置 driver参数

我们首先要通过Op t i on 对象（比如说Ch rom eOp t i on s）设置监控浏览器日志，旧版本的Se len ium是通过DesiredCap a bi li t ie s设置的，下面是新版本的写法

from selenium.webdriver import Chrome, ChromeOptions
from selenium.webdriver.chrome.service import Service
from selenium.webdriver.common.by import By
from selenium.webdriver.support import expected_conditions
from selenium.webdriver.support.wait import WebDriverWait

options = ChromeOptions()
options.add_argument("--no-sandbox")
options.add_argument("--allow-running-insecure-content")
options.add_argument("--ignore-certificate-errors")
options.add_argument("--disable-single-click-autofill")
options.add_argument("--disable-autofill-keyboard-accessory-view[8]")
options.add_argument("--disable-full-form-autofill-ios")
options.add_experimental_option('perfLoggingPrefs', {
    'enableNetwork': True,
    'enablePage': False,
})
options.set_capability("goog:loggingPrefs", {
    'browser': 'ALL',
    'performance': 'ALL',
})
options.set_capability("goog:perfLoggingPrefs", {
    'enableNetwork': True,
    'enablePage': False,
    'enableTimeline': False
})

3.请求网页

现在实例化一个driver，发起一个网页请求，我这里使用WebDriverWait显式等待的方式等待某个元素出现，你也可以隐式等待或者直接sleep，如果你不等待，异步请求还没加载完就开始获取，你可能会拿不到想要的数据

service = Service(executable_path=executable_path)
driver = Chrome(service=service, options=options)
driver.execute_cdp_cmd("Page.addScriptToEvaluateOnNewDocument",
                       {"source": """Object.defineProperty(navigator, 'webdriver', {get: () => undefined})"""})
driver.get(page_url)
wait = WebDriverWait(driver, 15, 0.5)
try:
    wait.until(expected_conditions.presence_of_element_located((By.CLASS_NAME, "item ")))
except Exception as e:
    print("WebDriverWait.until timeout error: {}".format(e))
html = driver.execute_script("return document.documentElement.outerHTML")

4.处理日志

访问一下driver的log_types属性可以获取到所有日志类型，遍历它，通过get_log()方法获取对应的日志，之后再过滤出自己想要的日志就行。

比如说，我这里是过滤出所有Network.requestWillBeSent的日志，即发送异步请求的数据，因为我需要该请求的请求头，如果是响应类型的日志（Network.responseReceived），它只包含响应头。具体支持的类型可以参考谷歌devtools的文档

如果需要过滤出Ajax（XHR）请求，可以根据日志的params里的type进行判断，也可以通过它判断

sign_dict = dict()  # 用来存储自己想要的数据
for log_type in driver.log_types:
    perf_list = driver.get_log(log_type)
    for row_log in perf_list:
        try:
            log_json = json.loads(row_log['message'])
            message_log = log_json['message']
        except Exception as e:
            print(e)
            continue
        if message_log.get('method') != 'Network.requestWillBeSent':
            continue
        if message_log.get("params", {}).get("type", "").upper() != "XHR":
            continue
        headers = message_log['params'].get('request', {}).get('headers')
        if not headers:
            continue
        x_sign = headers.get('X-Sign')
        if not x_sign:
            continue
        x_app_id = headers.get('X-AppID')
        x_ts = headers.get('X-Ts')
        print("success:", x_sign, x_app_id, x_ts)
        req_url = message_log['params'].get('request', {}).get('url')
        key = os.path.split(req_url.split("?")[0])[1]
        sign_dict[key] = {"X-AppID": x_app_id, "X-Sign": x_sign, "X-Ts": x_ts}

注意，如果你想要响应体，Network.responseReceived类型的日志的response字段是没有响应体的，你需要通过params字段里的requestId获取，参考代码如下

res_body_dict = dict()
for log_type in driver.log_types:
    perf_list = driver.get_log(log_type)
    for row_log in perf_list:
        try:
            log_json = json.loads(row_log['message'])
            message_log = log_json['message']
        except Exception as e:
            print(e)
            continue
        if message_log.get('method') != 'Network.responseReceived':
            continue
        if message_log.get("params", {}).get("type", "").upper() != "XHR":
            continue
        request_id = message_log['params'].get("requestId")
        if not request_id:
            continue
        req_url = message_log['params'].get('response', {}).get('url')
        key = os.path.split(req_url.split("?")[0])[1]
        content = driver.execute_cdp_cmd('Network.getResponseBody', {'requestId': request_id})
        body = None
        try:
            body = json.loads(content["body"])
        except Exception as e:
            print("get_unisat_data_by_selenium() json loads error: {}, content:{}".format(e, content))
        res_body_dict[key] = body

5.完整代码

上面的完整参考代码如下

import json
import os.path

from selenium.webdriver import Chrome, ChromeOptions
from selenium.webdriver.chrome.service import Service
from selenium.webdriver.common.by import By
from selenium.webdriver.support import expected_conditions
from selenium.webdriver.support.wait import WebDriverWait


def get_selenium_driver(executable_path=r"E:webdriverchromedriver.exe"):
    options = ChromeOptions()
    options.add_argument("--no-sandbox")
    options.add_argument("--allow-running-insecure-content")
    options.add_argument("--ignore-certificate-errors")
    options.add_argument("--disable-single-click-autofill")
    options.add_argument("--disable-autofill-keyboard-accessory-view[8]")
    options.add_argument("--disable-full-form-autofill-ios")
    options.add_experimental_option('perfLoggingPrefs', {
        'enableNetwork': True,
        'enablePage': False,
    })
    options.set_capability("goog:loggingPrefs", {
        'browser': 'ALL',
        'performance': 'ALL',
    })
    options.set_capability("goog:perfLoggingPrefs", {
        'enableNetwork': True,
        'enablePage': False,
        'enableTimeline': False
    })
    service = Service(executable_path=executable_path)
    driver = Chrome(service=service, options=options)
    driver.execute_cdp_cmd("Page.addScriptToEvaluateOnNewDocument",
                           {"source": """Object.defineProperty(navigator, 'webdriver', {get: () => undefined})"""})

    return driver


def get_sign_by_selenium(page_url):
    driver = get_selenium_driver()
    driver.execute_cdp_cmd("Page.addScriptToEvaluateOnNewDocument",
                           {"source": """Object.defineProperty(navigator, 'webdriver', {get: () => undefined})"""})
    driver.get(page_url)
    wait = WebDriverWait(driver, 15, 0.5)
    try:
        wait.until(expected_conditions.presence_of_element_located((By.CLASS_NAME, "item ")))
    except Exception as e:
        print("WebDriverWait.until timeout error: {}".format(e))
    # html = driver.execute_script("return document.documentElement.outerHTML")
    # with open(r"C:UsersadminDesktoptesttest.html", "w") as f:
    #     f.write(html)
    # time.sleep(10)
    sign_dict = dict()
    for log_type in driver.log_types:
        perf_list = driver.get_log(log_type)
        for row_log in perf_list:
            try:
                log_json = json.loads(row_log['message'])
                message_log = log_json['message']
            except Exception as e:
                print(e)
                continue
            if message_log.get('method') != 'Network.requestWillBeSent':
                continue
            if message_log.get("params", {}).get("type", "").upper() != "XHR":
                continue
            headers = message_log['params'].get('request', {}).get('headers')
            if not headers:
                continue
            x_sign = headers.get('X-Sign')
            if not x_sign:
                continue
            x_app_id = headers.get('X-AppID')
            x_ts = headers.get('X-Ts')
            print("success:", x_sign, x_app_id, x_ts)
            req_url = message_log['params'].get('request', {}).get('url')
            key = os.path.split(req_url.split("?")[0])[1]
            sign_dict[key] = {"X-AppID": x_app_id, "X-Sign": x_sign, "X-Ts": x_ts}
    return sign_dict


def get_unisat_data_by_selenium(page_url):
    driver = get_selenium_driver()
    driver.execute_cdp_cmd("Page.addScriptToEvaluateOnNewDocument",
                           {"source": """Object.defineProperty(navigator, 'webdriver', {get: () => undefined})"""})
    driver.get(page_url)
    wait = WebDriverWait(driver, 15, 0.5)
    try:
        wait.until(expected_conditions.presence_of_element_located((By.CLASS_NAME, "item ")))
    except Exception as e:
        print("WebDriverWait.until timeout error: {}".format(e))
    res_body_dict = dict()
    for log_type in driver.log_types:
        perf_list = driver.get_log(log_type)
        for row_log in perf_list:
            try:
                log_json = json.loads(row_log['message'])
                message_log = log_json['message']
            except Exception as e:
                print(e)
                continue
            if message_log.get('method') != 'Network.responseReceived':
                continue
            if message_log.get("params", {}).get("type", "").upper() != "XHR":
                continue
            request_id = message_log['params'].get("requestId")
            if not request_id:
                continue
            req_url = message_log['params'].get('response', {}).get('url')
            key = os.path.split(req_url.split("?")[0])[1]
            content = driver.execute_cdp_cmd('Network.getResponseBody', {'requestId': request_id})
            body = None
            try:
                body = json.loads(content["body"])
            except Exception as e:
                print("get_unisat_data_by_selenium() json loads error: {}, content:{}".format(e, content))
            res_body_dict[key] = body
    return res_body_dict


if __name__ == '__main__':
    url = "https://unisat.io/brc20?q=bc1pkmnh3nj89uns3yp2mtqqxjns65vy6ca6n5jvp4s8ua8nke69cnjs987vtp"
    print("get_sign_by_selenium(url):", get_sign_by_selenium(url))
    # print("get_unisat_data_by_selenium(url):", get_unisat_data_by_selenium(url))