Dynamic Routes

noreply@example.com (AG Sayyed) — Fri, 25 Jul 2025 00:00:00 +0000

This document explores dynamic routing in Flask, including how to pass parameters in URLs, call external APIs, and use parameter types for robust RESTful endpoints. It covers practical examples for integrating external data and validating user input in web applications.

Calling External APIs in Flask

Flask can interact with external APIs using the Python requests library. This allows applications to fetch, process, and return data from third-party services.

 1import requests
 2from flask import Flask, jsonify
 3
 4app = Flask(__name__)
 5
 6@app.route('/author')
 7def author_info():
 8 res = requests.get('https://openlibrary.org/search/authors.json?q=Michael+Crichton')
 9 if res.status_code == 200:
10 return jsonify(res.json())
11 elif res.status_code == 404:
12 return {'message': 'Something went wrong.'}, 404
13 else:
14 return {'message': 'Server error.'}, 500

This example fetches author data from the OpenLibrary API and returns the result to the client, handling different status codes appropriately.

Error Handling

noreply@example.com (AG Sayyed) — Fri, 25 Jul 2025 00:00:00 +0000

This document covers HTTP status codes, error handling in Flask, and best practices for returning error responses from API endpoints. It explains status code categories, custom error responses, and application-level error handlers for robust API design.

Understanding HTTP Status Codes

Every HTTP response includes a three-digit status code that indicates the result of the request. Status codes are grouped into categories:

Code Range	Category	Description
100–199	Informational	Request received, continuing process
200–299	Success	Request received and processed successfully
300–399	Redirection	Further action needed to complete request
400–499	Client Error	Error in the request from the client
500–599	Server Error	Error on the server side

Common codes include:

Api on Ghafoor's Personal Blog

Dynamic Routes

Calling External APIs in Flask

Error Handling

Understanding HTTP Status Codes