API Routes

API routes let you build JSON endpoints alongside your pages.

Creating an API Route

Create a +server.ts file and export named HTTP verb functions:

src/routes/api/hello/+server.ts

import type { RequestEvent } from "bosia";

export function GET({ params, locals }: RequestEvent) {
  return Response.json({
    message: "Hello from Bosia API!",
    user: locals.user,
  });
}

export async function POST({ request }: RequestEvent) {
  const body = await request.json().catch(() => ({}));
  return Response.json({ received: body });
}

Supported exports: GET, POST, PUT, PATCH, DELETE, OPTIONS.

RequestEvent

Every handler receives a RequestEvent:

Property	Type	Description
request	Request	The raw Web API Request object
url	URL	Parsed request URL
params	Record<string, string>	Dynamic route parameters
locals	Record<string, any>	Data set by middleware hooks
cookies	Cookies	Read/write cookies

Returning Responses

Return standard Web API Response objects:

// JSON
return Response.json({ ok: true });

// Custom status
return Response.json({ error: "Not found" }, { status: 404 });

// Plain text
return new Response("Hello", { status: 200 });

// Custom headers
return new Response(null, {
  status: 204,
  headers: { "X-Custom": "value" },
});

Dynamic API Routes

Use dynamic segments just like pages:

src/routes/api/users/[id]/+server.ts  →  /api/users/123

export function GET({ params }: RequestEvent) {
  return Response.json({ userId: params.id });
}

export function DELETE({ params }: RequestEvent) {
  return Response.json({ deleted: params.id });
}

Method Not Allowed

If a request hits a +server.ts that doesn’t export the requested method, Bosia responds with 405 Method Not Allowed and an Allow header listing the supported methods.

Accessing Locals

Data set in hooks.server.ts is available in every API handler:

export function GET({ locals }: RequestEvent) {
  if (!locals.user) {
    return Response.json({ error: "Unauthorized" }, { status: 401 });
  }
  return Response.json({ user: locals.user });
}