Python请求Trulia GraphQL接口遇POST body missing错误求助

问题根源 #

请求失败有两个核心原因：

• data字符串开头的${是curl的变量语法，转成Python时未清理，导致JSON格式完全无效，服务器无法解析请求体。
• 虽然请求头设置了content-type: application/json，但直接用data传递字符串时，若格式不合法，服务器会判定请求体缺失。

修复步骤及代码 #

1. 清理curl残留的变量语法，改用Python字典定义请求体，避免手动拼接JSON的转义错误；
2. 使用requests.post的json参数替代data，让requests自动完成JSON序列化，确保请求格式符合要求。

修正后的代码：

import requests

headers = {
    'authority': 'www.trulia.com',
    'accept': '*/*',
    'accept-language': 'en-US,en;q=0.9',
    'content-type': 'application/json',
    'cookie': 'tlftmusr=220127r6dy3udjlwtjr01eae5y1am065; s_fid=506AFCB7DCC3B70E-04D45F7B245F2989; zjs_anonymous_id=%22220127r6dy3udjlwtjr01eae5y1am065%22; _pxvid=634490ac-7faf-11ec-97bb-46596545526e; s_vi=[CS]v1|30F97FF6092382A7-400009A2368190B5[CE]; __gads=ID=0eb268a112aea6f0:T=1643315195:S=ALNI_MaLaqYG67wdCJeuAFsdIERsHIa4-g; commute=0|6|true; zg_anonymous_id=%22cc042b2d-29ef-4e76-b308-28aeaff9a2e1%22; g_state={"i_l":0}; stpa=91bdcbde35bfe55ff02e350d14f75e445b42ea3e41f2e46a203989d356bff928; stpr=cdcff13428427b5ddb1781c5d4859c89c6acef163f2b209d1646a1120a69b9a0; _pbjs_userid_consent_data=3524755945110770; _lr_env_src_ats=true; pbjs_identitylink=AhQek2Yd4okYD6kzV87whVYRVpd5gpbKXI814m-bhzxpNhZkGc6-cA7a7IWQn4fqY6mRjIPp7V1HixTEIYOnwEGtdpg2T68gnHO19Y1hvTvGTuMisyzrA_C177JiSpHmkBQ6; _csrfSecret=chVcTCGkojJf4aCkyL4Tb9W3; pxcts=70ff9020-11bf-11ed-801e-724c78677a6a; s_cc=true; branch_banner_closed=true; QSI_S_ZN_aVrRbuAaSuA7FBz=v:0:0; _lr_geo_location=GB; _pxhd=nuRoQ8PYpvv5IFHZqpNRyclkZmK2j5vYVdTClh/G2Lm2h8FzsW243Ht4FF3PyNSfdSDFcidjR6Cjanayd0MKGw==:DzVg679PRtFcVxHRZ9FRr8BJYXUOKB-zxP6g6iFwwgaaancqb/io9qDdHLhAfFJF9/6CNgdM1pddBEnzcOYqc1oKFtTbU2RuB3CWbZA8rC8=; _lr_sampling_rate=100; __gpi=UID=0000044f4a7ee8c2:T=1649400644:RT=1660020564:S=ALNI_MYBilKp0qq4hojdg9AyNF4Fhe1OnA; trul_visitTimer=1660019642110_1660021418934; OptanonConsent=isIABGlobal=false&datestamp=Mon+Aug+08+2022+22%3A03%3A39+GMT-0700+(Pacific+Daylight+Time)&version=5.8.0&landingPath=NotLandingPage&groups=1%3A1%2C0_234869%3A1%2C3%3A1%2C4%3A1%2C0_234866%3A1%2C0_234867%3A1%2C0_234868%3A1%2C0_240782%3A1%2C0_240783%3A1%2C0_240780%3A1%2C0_234871%3A1%2C0_240781%3A1%2C0_234872%3A1%2C0_234873%3A1%2C0_234874%3A1%2C0_234875%3A1%2C0_234876%3A1%2C0_234877%3A1&AwaitingReconsent=false; zjs_user_id=%2259788808%22; s_sq=%5B%5BB%5D%5D',
    'origin': 'https://www.trulia.com',
    'referer': 'https://www.trulia.com/p/oh/bedford/59-john-st-bedford-oh-44146--1009668993',
    'sec-ch-ua': '".Not/A)Brand";v="99", "Google Chrome";v="103", "Chromium";v="103"',
    'sec-ch-ua-mobile': '?0',
    'sec-ch-ua-platform': '"macOS"',
    'sec-fetch-dest': 'empty',
    'sec-fetch-mode': 'cors',
    'sec-fetch-site': 'same-origin',
    'user-agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.0.0 Safari/537.36',
    'x-bc-buildercommunitydata': '1',
    'x-contextual-highlights': '1',
    'x-csrf-token': 'OccCsutt-ZVwpowv1P9gB9RCaSrqkPZ02WJg',
    'x-papi-fall-back-disabled': '0',
    'x-pdc-api-enabled': '0',
    'x-rc-bls': '1',
    'x-request-id': 'client-92d6a7c4-68c0-40ed-89e8-a267d4269e50',
    'x-zg-search-enabled': '0',
}

params = (
    ('opname', 'WEB_fetchAffordabilityQuery'),
    ('transactionId', 'client-92d6a7c4-68c0-40ed-89e8-a267d4269e50'),
)

# 用Python字典定义请求体，避免手动拼接JSON的格式错误
payload = {
    "operationName": "WEB_fetchAffordabilityQuery",
    "variables": {"url": "/p/oh/bedford/59-john-st-bedford-oh-44146--1009668993"},
    "query": """query WEB_fetchAffordabilityQuery($url: String!) {
 homeDetailsByUrl(url: $url) {
 ... on HOME_Details {
 ...HomeDetailsMortgageInfoAndHoaFeeFragment
 location {
 city
 stateCode
 zipCode
 __typename
 }
 price {
 ... on HOME_ValuationPrice {
 price
 __typename
 }
 ... on HOME_LastSoldPrice {
 price
 __typename
 }
 ... on HOME_SinglePrice {
 price
 __typename
 }
 __typename
 }
 metadata {
 compositeId
 __typename
 }
 __typename
 }
 __typename
 }
}

fragment HomeDetailsMortgageInfoFragment on HOME_MortgageInfo {
 ctaUrls {
 purchaseRates
 postLead
 __typename
 }
 mortgageInquiryCta(useRefinancePreQualifyLink: true) {
 text
 url
 __typename
 }
 rates {
 defaultRates {
 taxRate
 interestRate
 __typename
 }
 taxRate
 interestRates(creditScore: EXCELLENT) {
 loanDuration
 rate
 creditScore
 displayName
 loanType
 __typename
 }
 __typename
 }
 defaults {
 homePrice {
 price
 __typename
 }
 loanDuration
 downPaymentPercentage
 insurance {
 price
 __typename
 }
 __typename
 }
 mortgageEstimateDisclaimer
 __typename
}

fragment HomeDetailsHoaFeeFragment on HOME_HoaFee {
 period
 amount {
 price
 __typename
 }
 __typename
}

fragment HomeDetailsMortgageInfoAndHoaFeeFragment on HOME_Details {
 ... on HOME_Property {
 hoaFee {
 ...HomeDetailsHoaFeeFragment
 __typename
 }
 mortgageInfo {
 ...HomeDetailsMortgageInfoFragment
 __typename
 }
 __typename
 }
 ... on HOME_FloorPlan {
 hoaFee {
 ...HomeDetailsHoaFeeFragment
 __typename
 }
 mortgageInfo {
 ...HomeDetailsMortgageInfoFragment
 __typename
 }
 __typename
 }
 ... on HOME_BuilderCommunity {
 hoaFee {
 ...HomeDetailsHoaFeeFragment
 __typename
 }
 mortgageInfo {
 ...HomeDetailsMortgageInfoFragment
 __typename
 }
 __typename
 }
 __typename
}"""
}

# 使用json参数传递数据，requests自动处理序列化和Content-Type头
response = requests.post('https://www.trulia.com/graphql', headers=headers, params=params, json=payload)
print(response.status_code)
print(response.json())

额外说明 #

• 用Python字典定义请求体比手动拼接JSON字符串更可靠，能避免引号转义、语法残留等问题。
• 若坚持使用data参数，需确保字符串是完全合法的JSON（移除${等curl语法，所有引号正确转义），同时保持content-type: application/json头的正确设置。

内容的提问来源于stack exchange，提问作者Luka Jozić