Examples: learn by building

The quickest way to learn Mojara is to create a small app, run it, then change its behavior.

Example 1. Hello World

from mojara import App, Request, Response

def hello(req: Request) -> Response:
    return Response.html("<h1>Hello, Mojara!</h1>")

def main() raises:
    var app = App()
    app.get("/", hello)
    app.run(port=8000)

Run mojara dev and open http://127.0.0.1:8000/.

Example 2. JSON status endpoint

def status(req: Request) -> Response:
    return Response.json('{"service":"notes","status":"ok"}')

Register app.get("/api/status", status). Send curl http://127.0.0.1:8000/api/status and inspect the JSON response.

Example 3. Validate an email

def subscribe(req: Request) -> Response:
    var email = req.json().get("email", "")
    if "@" not in email:
        return Response.json('{"error":"Provide a valid email"}', status=422)
    return Response.json('{"subscribed":true}', status=201)

Register app.post("/api/subscribe", subscribe). Try:

curl -i -X POST http://127.0.0.1:8000/api/subscribe \
  -H "Content-Type: application/json" -d '{"email":"amina@example.com"}'

Example 4. Query a database

from mojara.dbclient import PooledDatabase

var db = PooledDatabase("host=127.0.0.1 dbname=mojara_dev", capacity=2)
var lease = db.acquire()
var rows = lease.query("SELECT 1 AS number")
print(rows.cell(0, 0))
lease.release()
db.close()

This uses the PostgreSQL pool API. The full connection and transaction walkthrough is in PostgreSQL and Connection pools.

Choose your next lesson: Routes, Requests and forms, Databases, Deployment.