Working with JSON

Definition: JSON (JavaScript Object Notation) is a lightweight, text-based format used for storing and transporting data. In Python, the built-in json module provides tools to convert JSON strings into Python dictionaries and vice versa.

Why: JSON is the universal language of data exchange on the web. Web applications, APIs, and configuration files rely heavily on JSON to send data back and forth between a server and a client or between different applications.

Common JSON Operations

• Parsing JSON (Decoding): Converting a JSON string into a Python object (like a dictionary or list) using json.loads().
• Converting to JSON (Encoding): Converting a Python object into a clean JSON formatted string using json.dumps().

Example (Parsing JSON)

import json

# A sample JSON string (looks like a Python dictionary, but enclosed in single quotes)
x = '{"name":"Ravi","age":20}'

# Convert the JSON string into a Python dictionary
y = json.loads(x)

# Accessing data using standard dictionary keys
print(y["name"])  # Output: Ravi

Key Notes

• Data Type Mapping: When you parse a JSON string, Python automatically converts JSON types to its native types (e.g., a JSON object becomes a Python dict, an array becomes a list, and true/false values become True/False).
• File Operations: If you want to read or write JSON data directly from or to an external physical file rather than working with text strings, you use json.load() and json.dump() (without the "s").