How to Merge Two JSON Files with Python: Adding New Key-Value Pairs

Learn how to efficiently `merge two JSON files` in Python by adding new key-value pairs, even at deeper levels. This step-by-step guide simplifies the merging process and ensures valid JSON output.
---

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: Merge 2 json files with python adding new "key":"value"

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Merging JSON Files in Python

Combining data from multiple JSON files can seem daunting, especially when the structures are complex and layered. In this post, we’ll tackle how to merge two JSON files in Python and add new key-value pairs, even at deeper levels.

The Problem

Imagine you have two JSON files:

File One contains information about individuals and their associated tags:

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

File Two has hierarchical information with gear associated with each individual:

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

The goal is to create a third file that merges both with the following structure:

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

Key Challenges

The nested structure of the second file can complicate traversing and merging.

Ensuring that the output file adheres to valid JSON format.

The Solution

Here's a detailed breakdown of how to effectively merge these JSON files using Python.

Step 1: Import the Required Library

First, make sure to import the json library, which will allow you to read and write JSON data.

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

Step 2: Define the Update Function

Create a function that takes the new data and the target data. This function will iterate through the keys and recursively merge the relevant information.

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

Step 3: Load Data from JSON Files

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

Step 4: Merge the Data

Now, simply call the update function and pass in the loaded data:

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

Step 5: Write the Merged Data to a New JSON File

Finally, save the merged data back into a new file:

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

Important Notes

The recursive nature of the update function allows it to work with any level of nesting in the JSON structure.

This method keeps your code clean, efficient, and can handle complex data structures.

Conclusion

By following these steps, you should be able to merge two JSON files effortlessly while adding new values to existing keys, regardless of how deep they are nested. This technique is essential for data manipulation tasks in Python, simplifying the management of hierarchical data structures.

Now you're equipped to handle JSON merging like a pro! Happy coding!