请求返回400，有效负载中包含JSON，有效负载中的字符串返回200

Question

使用在POST请求后返回嵌套JSON数据集的API。它期望有效负载为：

payload = '{"metrics":[ {"name":"Jobs.2019"}, {"name", "Jobs.2018"], "constraints": ["dimensionName": "Area", "map": {"Adams, OH":["39001"],"Allen, OH":["39003"]} }, {"dimensionName": "Industry", "map": {"Crop Production":["111000"]} } ] }'

其中，{"Adams，OH":" 391001 "}将标签放在FIPS码391001上以供查找。问题是俄亥俄州有88个县，美国每个州都有更多的县。

我想我可以把这些县作为counties.json

{
   "Adams, OH":[
      "39001"
   ],
   "Allen, OH":[
      "39003"
   ]
}

并在我的脚本中设置变量

with open('data.json', 'r') as json_file:
    counties = json.load(json_file)

然后调用我的请求

metrics = '[{"name": "Jobs.2019" }, {"name": "Jobs.2018"}, {"name": "Jobs.2017"}, {"name": "Jobs.2016"}, {"name": "Jobs.2015"}, {"name": "Jobs.2020"}, {"name": "Estab.2019" }, {"name": "Estab.2018"}, {"name": "Estab.2017"}, {"name": "Estab.2016"}, {"name": "Estab.2015"}, {"name": "Estab.2014"}, {"name": "EPW.2019"}, {"name": "EPW.2018"}, {"name": "EPW.2017"}, {"name": "EPW.2016"}, {"name": "EPW.2015"}, {"name": "EPW.2014"}]'

payload = f'{{"metrics": {metrics},  "constraints": [{{"dimensionName": "Area", "map": {counties} }}, {{"dimensionName": "Industry", "map": {{"Crop Production":["111000"]}}  ]}}'

result = requests.request("POST", url, headers=headers, data=payload)

但是，这将返回一个错误请求的<400>，我的有效负载如下所示：

{"metrics": [{"name": "Jobs.2019" }, {"name": "Jobs.2018"}, {"name": "Jobs.2017"}, {"name": "Jobs.2016"}, {"name": "Jobs.2015"}, {"name": "Jobs.2020"}, {"name": "Estab.2019" }, {"name": "Estab.2018"}, {"name": "Estab.2017"}, {"name": "Estab.2016"}, {"name": "Estab.2015"}, {"name": "Estab.2014"}, {"name": "EPW.2019"}, {"name": "EPW.2018"}, {"name": "EPW.2017"}, {"name": "EPW.2016"}, {"name": "EPW.2015"}, {"name": "EPW.2014"}],  "constraints": [{"dimensionName": "Area", "map": {'Adams, OH': ['39001'], 'Allen, OH': ['39003']} }, {"dimensionName": "Industry", "map": {"Crop Production":["111000"]}  ]}

但是，当我调用它时：

metrics = '[{"name": "Jobs.2019" }, {"name": "Jobs.2018"}, {"name": "Jobs.2017"}, {"name": "Jobs.2016"}, {"name": "Jobs.2015"}, {"name": "Jobs.2020"}, {"name": "Estab.2019" }, {"name": "Estab.2018"}, {"name": "Estab.2017"}, {"name": "Estab.2016"}, {"name": "Estab.2015"}, {"name": "Estab.2014"}, {"name": "EPW.2019"}, {"name": "EPW.2018"}, {"name": "EPW.2017"}, {"name": "EPW.2016"}, {"name": "EPW.2015"}, {"name": "EPW.2014"}]'

payload = '{"metrics":' + metrics + ',"constraints": [{"dimensionName": "Area", "map": {"Adams, OH":["39001"],"Allen, OH":["39003"]} }, {"dimensionName": "Industry", "map": {"Crop Production":["111000"]} } ] }'

result = requests.request("POST", url, headers=headers, data=payload)

我收到一个负载如下的<200>：

{"metrics":[{"name": "Jobs.2019" }, {"name": "Jobs.2018"}, {"name": "Jobs.2017"}, {"name": "Jobs.2016"}, {"name": "Jobs.2015"}, {"name": "Jobs.2020"}, {"name": "Estab.2019" }, {"name": "Estab.2018"}, {"name": "Estab.2017"}, {"name": "Estab.2016"}, {"name": "Estab.2015"}, {"name": "Estab.2014"}, {"name": "EPW.2019"}, {"name": "EPW.2018"}, {"name": "EPW.2017"}, {"name": "EPW.2016"}, {"name": "EPW.2015"}, {"name": "EPW.2014"}],"constraints": [{"dimensionName": "Area", "map": {"Adams, OH":["39001"],"Allen, OH":["39003"]} }, {"dimensionName": "Industry", "map": {"Crop Production":["111000"]} } ] }

据我所见，一切都是完全相同的，解释器将JSON输出为单引号(')而不是双引号(")，但根据我的记忆，请求模块接收相同的有效负载。

我觉得我错过了一些明目张胆的愚蠢和明显的东西，但在这一点上，我已经尝试了我的工具腰带中的每一个技巧。

Answer 1

问题是，当您读取JSON文件时，json.load会返回一个Python dict。然后，当您使用它作为f-string的输入时，您只是获得了该dict的Python表示，而不是一个有效的JSON对象-正如您已经注意到的，它被表示为单引号，这在JSON中是无效的- JSON对于单引号和双引号非常挑剔。

您可以使用json.dumps(counties)而不是counties。

然而，我建议你做一些不同的事情。不需要操作字符串来创建JSON对象，而是在Python中完成这项工作，然后根据需要转换为JSON。这就是json库为您提供的帮助！

例如，您可以执行以下操作，这要简单得多：

metrics = json.loads('[{"name": "Jobs.2019" }, {"name": "Jobs.2018"}, {"name": "Jobs.2017"}, {"name": "Jobs.2016"}, {"name": "Jobs.2015"}, {"name": "Jobs.2020"}, {"name": "Estab.2019" }, {"name": "Estab.2018"}, {"name": "Estab.2017"}, {"name": "Estab.2016"}, {"name": "Estab.2015"}, {"name": "Estab.2014"}, {"name": "EPW.2019"}, {"name": "EPW.2018"}, {"name": "EPW.2017"}, {"name": "EPW.2016"}, {"name": "EPW.2015"}, {"name": "EPW.2014"}]')

payload = {"metrics": metrics,
           "constraints": [{"dimensionName": "Area",
                            "map": counties},
                           {"dimensionName": "Industry",
                            "map": {"Crop Production": ["111000"]}}]}

result = requests.post(url, headers=headers, json=payload)