How I Merged and Validated Two JSON Files in Go

Go has great support for reading files and decoding JSON using only the standard library. I wanted to learn how Go handles file I/O, JSON, and type safety. Here’s how I did it, what I learned, and some alternatives I found along the way.

When I started learning Go, my first real task was to merge two JSON files and validate the result. It sounded easy. It turned out to be a great way to learn how Go handles file I/O, JSON, maps, and type safety.

Here’s how I did it, what I learned, and some alternatives I found along the way.

The Task

1. Read two JSON files.
2. Merge them into a single structure.
3. Validate the result to make sure certain fields exist and are of the correct type.
4. Write the final JSON to a new file.

Step 1: Reading ...