Migrating from Koa

Shokupan’s context-based approach is heavily inspired by Koa, making it a very natural transition.

Key Differences

1. Return Value: Shokupan handlers return data directly instead of setting ctx.body.
2. Routing: Shokupan has a built-in router; Koa requires koa-router or similar.
3. Body Parsing: Built-in; no need for koa-bodyparser.

Middleware

Both frameworks use similar middleware patterns with await next().

Koa:

app.use(async (ctx, next) => {
    await next();
    ctx.set('X-Response-Time', '10ms');
});

Shokupan:

app.use(async (ctx, next) => {
    // Wait for downstream
    await next();

    // Modify headers after handler completes
    ctx.response.headers.set('X-Response-Time', '10ms');
});

Context Comparison

Feature	Koa	Shokupan
Request Body	ctx.request.body (with middleware)	ctx.body (built-in)
Query String	ctx.query	ctx.query (URLSearchParams)
Sending Text	ctx.body = 'Hello'	return 'Hello' or return ctx.text('Hello')
Sending JSON	ctx.body = { foo: 'bar' }	return { foo: 'bar' }
Status Code	ctx.status = 404	return ctx.text('Not Found', 404)

Migration Checklist

Change `ctx.body = ...` to `return ...` or `return ctx.text(...)` Remove Koa middleware Update `ctx.request.query` usage to `ctx.query.get()`

Next Steps

• Core Concepts - Learn Shokupan patterns
• Controllers - Use Class-based routing