Structuring API requests

Path Parameters

• Used to identify a specific resource or resource instance.
• Integral to the URL path, making them part of the endpoint.

Usage:

• Syntax: /resource/{parameter}/subresource/{subparameter}
• Example: /users/123 where 123 is a path parameter identifying a user.

Characteristics:

• Typically used for resource identification and hierarchy.
• Essential to the API’s endpoint structure.
• Generally static and fixed.

Code Example (Express.js):

app.get('/users/:userId', (req, res) => {
    const userId = req.params.userId;
    // Fetch user by userId
    res.send(`User ID: ${userId}`);
});

Query Parameters

• Used to filter, sort, or modify the request’s scope or behavior.

• Optional and appended to the URL after the question mark ?.

• Syntax: /resource?param1=value1&param2=value2

• Example: /products?category=electronics&priceRange=100-500 where category and priceRange are query parameters.

Characteristics:

• Typically used for searching, filtering, and pagination.
• Flexible and can be combined in various ways.
• Not part of the endpoint structure but appended to the URL.

app.get('/products', (req, res) => {
    const category = req.query.category;
    const priceRange = req.query.priceRange;
    // Fetch products based on category and priceRange
    res.send(`Category: ${category}, Price Range: ${priceRange}`);
});