{"id":1083,"date":"2018-08-02T22:51:45","date_gmt":"2018-08-02T14:51:45","guid":{"rendered":"https:\/\/www.techcoil.com\/blog\/?p=1083"},"modified":"2021-01-08T18:13:41","modified_gmt":"2021-01-08T10:13:41","slug":"how-to-upload-a-file-and-some-data-through-http-multipart-in-python-3-using-the-requests-library","status":"publish","type":"post","link":"https:\/\/www.techcoil.com\/blog\/how-to-upload-a-file-and-some-data-through-http-multipart-in-python-3-using-the-requests-library\/","title":{"rendered":"How to upload a file and some data through HTTP multipart in Python 3 using the requests library"},"content":{"rendered":"

Undeniably, the HTTP protocol<\/a> had become the dominant communication protocol between computers. <\/p>\n

Through the HTTP protocol, a HTTP client<\/a> can send data to a HTTP server<\/a>. For example, a client can upload a file and some data from to a HTTP server through a HTTP multipart request. <\/p>\n

If you are building that client with Python 3, then you can use the requests<\/a> library to construct the HTTP multipart request easily. <\/p>\n

In case you need it, this is how we can upload a file and some data through HTTP multipart in Python 3 using the requests<\/a> library. <\/p>\n

1. Define the file upload scenario<\/h2>\n

First, let us define the file upload scenario. <\/p>\n

Assume that we are building a Python 3 application for your Raspberry Pi 3<\/a>. Whenever a button is pressed, an image will be captured with the camera on your Raspberry Pi<\/a> along with temperature read from a DHT11 sensor<\/a>. <\/p>\n

Once we click the button, the Raspberry Pi 3 will snap a picture and make it available in its filesystem<\/a>.<\/p>\n

Given that, we will be building a function that will take a file path to an image and a float value for the temperature as input parameters. Given that, the function will upload the image file and the temperature to a server endpoint at http:\/\/www.example.com\/api\/v1\/sensor_data<\/code>. <\/p>\n

2. Install the requests library<\/h2>\n

In order to use the requests library, we need to install it by running the following pip command inside your Python environment:<\/p>\n

\r\npip install requests\r\n<\/pre>\n
If you are using a virtual environment to run your Python application on your Raspberry Pi<\/a>, then you can run the command after activating the virtual environment.<\/p>\n
3. Write the Python 3 function to upload the image file and temperature to the server endpoint<\/h2>\n
After you had installed the requests library, we can use the following codes to upload the image file and temperature value via a HTTP multipart request:<\/p>\n
\r\nimport requests\r\nimport os\r\n\r\nfunction send_data_to_server(image_path, temperature):\r\n        \r\n    image_filename = os.path.basename(image_path)\r\n\r\n    multipart_form_data = {\r\n        'image': (image_filename, open(image_path, 'rb')),\r\n        'temperature': ('', str(temperature)),\r\n    }\r\n\r\n    response = requests.post('http:\/\/www.example.com\/api\/v1\/sensor_data\/',\r\n                             files=multipart_form_data)\r\n\r\n    print(response.status_code)\r\n\r\n<\/pre>\n
The send_data_to_server<\/code> function accepts a path to an image and a temperature value as its input value. Once the function is being called, it first get the filename of the image from the path. <\/p>\n
After that, it constructs a dictionary with two multipart variables - image<\/code> and temperature<\/code>. Both variables and their values are represented by 2-tuples. The image<\/strong> variable is assigned a filename and a file handle to the actual image. On the other hand, as temperature<\/code> is a single value, the first element of the 2-tuple is empty while the second element contains the temperature as a string. <\/p>\n
Once we had constructed the dictionary to represent the content, we call requests.post<\/a> to send a HTTP multipart request to the server endpoint at http:\/\/www.example.com\/api\/v1\/sensor_data\/<\/code>.<\/p>\n
Lastly, the function prints the status of the HTTP response received from the server.<\/p>\n\n