Solving the DestinationPath Issue in Python Requests for File Uploads

Learn how to successfully upload a file with additional fields using Python Requests. Discover the key differences between `data` and `files` in multipart-form uploads.
---

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Python Requests Post - Additional field is not recognized for file upload

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Handling File Uploads with Additional Fields in Python Requests

When working with file uploads in Python, the Requests library simplifies the process of sending files to a server. However, sometimes you may encounter issues, especially when additional fields are required for the upload. One common frustration arises when attempting to upload a file along with a required field, like a path, only to receive an error indicating the field isn't recognized.

The Problem: DestinationPath Not Recognized

In a specific scenario, you might want to send a file along with an additional property named DestinationPath to an internal REST service. Here's a typical situation where you might run into issues:

You use the code below to attempt the upload:

[[See Video to Reveal this Text or Code Snippet]]

When executing the above code, you might receive a server error that states:

[[See Video to Reveal this Text or Code Snippet]]

This error indicates that despite specifying the DestinationPath, the server doesn't recognize it, leading to a failed file upload.

The Solution: Properly Structuring Your Request

Thanks to the insights from community members, we can resolve this issue by properly configuring our Requests library call. The core of the solution is to separate your data into two distinct parts: data (for regular parameters) and files (for file uploads). Below is the revised approach:

Revised Code Example

[[See Video to Reveal this Text or Code Snippet]]

Explanation of Changes

Separation of Parameters: Instead of combining your DestinationPath with the file in the files dictionary, you create a separate data dictionary for parameters. This ensures that each part is clearly categorized, helping the server to understand your request better.

Reading as Binary: When you read the file, ensure it's in binary mode (as shown in the example with "rb"). This is necessary for file uploads to ensure data integrity.

Summary

By structuring your upload properly, you allow the Requests library to send the required data correctly. This not only resolves the issue of unrecognized fields but also enhances the clarity and maintainability of your code. For anyone dealing with file uploads while needing to pass additional fields, remember to carefully distinguish between data and files when constructing your requests.

With this understanding, you'll be better equipped to navigate the Python Requests library and handle multipart-form uploads flawlessly.