如何使用python发送rest API（Google Vision的API）请求？

Question

我想我的问题相对简单和天真，但我是新手使用REST API所以我将不胜感激任何帮助或提示。

我正在尝试使用urllib（或其他我不需要安装的Python库）发送请求。根据他们的guide，格式为：

POST https://vision.googleapis.com/v1/images:annotate?key=YOUR_API_KEY

和JSON request format是：

{
  "requests":[
    {
      "image":{
        "content":"/9j/7QBEUGhvdG9...image contents...eYxxxzj/Coa6Bax//Z"
      },
      "features":[
        {
          "type":"LABEL_DETECTION",
          "maxResults":1
        }
      ]
    }
  ]
}

当我尝试在浏览器的URL行中发送以下文本（仅用于测试）时：

https://vision.googleapis.com/v1/images:{
  "requests":[
    {
      "image":{
        "content":"/9j/7QBEUGhvdG9eYxxxzj/Coa6Bax//Z"
      },
      "features":[
        {
          "type":"LABEL_DETECTION",
          "maxResults":1
        }
      ]
    }
  ]
}?key=my_api_key

遗憾的是我遇到了404错误。

我该怎么办？我应该使用任何库来生成请求吗？或者我应该将JSON请求放在URL中的其他位置？

Answer 1

如果您需要发送带有URL的Request Body，您可以使用CURL。要测试REST API，有一个名为POSTMAN的着名软件。通过使用此功能，您可以发送请求并接收响应。

卷曲，

curl -v -H "Content-Type: application/json" -X POST \
     -d '{"image":{"content":"/9j/7QBEUGhvdG9...image contents...eYxxxzj/Coa6Bax//Z"}, "features":[{"type":"LABEL_DETECTION","maxResults":1}]}' https://vision.googleapis.com/v1/images:annotate?key=YOUR_API_KEY

使用POSTMAN，您可以为其提供这些值并获得结果。

提供网址，

https://vision.googleapis.com/v1/images:annotate?key=YOUR_API_KEY

选择HTTP METHOD as，

POST

并在raw字段下添加REQUEST BODY并选择JSON(application/json)，

{
  "requests":[
    {
      "image":{
        "content":"/9j/7QBEUGhvdG9...image contents...eYxxxzj/Coa6Bax//Z"
      },
      "features":[
        {
          "type":"LABEL_DETECTION",
          "maxResults":1
        }
      ]
    }
  ]
}

Answer 2

这对我有用：

import base64
import requests
import json

URL = "https://vision.googleapis.com/v1/images:annotate?key=YOUR_TOKEN"

#image to base64, which is a long long text
def encode_image(image_path):
    with open(image_path, "rb") as image_file:
        return base64.b64encode(image_file.read())

#make api call
def image_request(image_path):
    data = {
            "requests":[
                        {
                        "image":{
                            "content":encode_image(image_path)
                                },
                        "features":[
                                    {
                                    "type":"LABEL_DETECTION", #other options: LABEL_DETECTION FACE_DETECTION LOGO_DETECTION CROP_HINTS WEB_DETECTION
                                    "maxResults": 10
                                    }
                                   ]
                        }
                    ]
}
    r = requests.post(URL, json = data)
    return r.text


#arg = path of image
def main(argv):
    api_answer = json.loads(image_request(argv[1]))
    try:
        rows = api_answer['responses'][0]['labelAnnotations']
    except:
        print(file_to_proccess)
        print(api_answer)
    data = []
    for item in rows:
        data.append([item['mid'], item['description'], item['score'], item['topicality']])

    # save somewhere the data list...

if __name__ == "__main__":
    main(sys.argv)