How to Use Python to Build a Basic Microservice (with a Real Jisho API Example)

Are you curious about what a microservice looks like in Python? In this article, I’ll walk you through creating a simple but complete microservice using Python and Flask that calls a real external API: the Jisho.org API.

The goal is to keep it minimal, readable, and useful — perfect for beginners or those wanting a practical example.

🧠 What This Microservice Does

This microservice exposes a simple webpage where users can:

1. Input a Japanese word (like 猫, 勉強, or 走る)
2. Submit the form
3. Get instant results from the Jisho.org API

The app has two main pages:

• / – The index page with a search form
• /search – The result page that fetches and displays definitions

This simulates a classic frontend-backend interaction flow, with the backend serving both HTML and dynamic content from a third-party API.

🗂️ Project Structure

Here’s how the project is organized:

jisho_microservice/
├── app.py                 # Main Python application
├── requirements.txt       # Dependencies (Flask, requests)
├── templates/             # HTML templates
│   ├── index.html         # Form page
│   └── result.html        # Results page
├── static/
│   └── style.css          # Simple styling for the pages

🔁 How It Works – Request Flow

1. User visits / → Sees a simple form to input a Japanese word.
2. Form submits to /search → The backend takes the word, sends a request to https://jisho.org/api/v1/search/words?keyword={word}.
3. Jisho API responds → We parse the JSON and display the result nicely on the webpage.

It’s a self-contained, classic example of:

• Frontend input
• Backend logic
• External API integration
• Displaying parsed results in the UI

🔑 Key Logic (Code Snippet)

Here’s the core Flask logic in app.py:

from flask import Flask, render_template, request
import requests

app = Flask(__name__)

JISHO_API = "https://jisho.org/api/v1/search/words?keyword="

@app.route('/')
def index():
    return render_template('index.html')

@app.route('/search', methods=['POST'])
def search():
    word = request.form['word']
    response = requests.get(JISHO_API + word)
    data = response.json()
    results = data['data'] if data['data'] else []
    return render_template('result.html', word=word, results=results)

if __name__ == '__main__':
    app.run(debug=True)

This short snippet demonstrates how to:

• Define routes using Flask
• Handle form input
• Call an external API using requests
• Pass API data into HTML templates for rendering

🔗 GitHub Repository

You can find the full working code here:
👉 https://www.github.com/jansenzjh/jisho_service

Feel free to clone, fork, or contribute!

🛣️ Future Roadmap

This is just the beginning. Here’s what I plan to add:

🚀 1. More APIs for Japanese Learners

• Kana to Kanji converter
• Furigana generator
• Grammar explanations

🔧 2. GitHub Actions

• CI/CD pipeline to lint, test, and deploy automatically

🏡 3. Self-Hosted Server

• Build a deployment pipeline to a VPS or home lab
• Use Docker to containerize the microservice

🌐 4. JSON API Version

• Add /api/search?word=猫 endpoint to return JSON instead of HTML

💬 Final Thoughts

This project is a simple but real example of a microservice that talks to an external API, processes the response, and renders a clean UI — all in under 100 lines of code. If you’re learning Python, Flask, or just want to see how microservices work at a small scale, this is a great place to start.