Context

The Context object provides access to request data and response methods.

Request Data

Path Parameters

// GET /users/123
let id = ctx.param("id");  // "123"?

Query Parameters

// GET /search?q=navi&limit=10
let q = ctx.query("q");           // "navi"?
let limit = ctx.query("limit");   // "10"?
let page = ctx.query("page");     // nil

Headers

let content_type = ctx.header("Content-Type");
let auth = ctx.header("Authorization");

Body

let body = ctx.body();  // Raw body as string

JSON Binding

struct CreateUser {
    name: string,
    email: string,
}

let user = try ctx.bind_json::<CreateUser>();

Response Methods

String

ctx.string("Hello, World!");

JSON

try ctx.json({
    "id": 1,
    "name": "Navi"
});

Status Code

ctx.status(201);
ctx.string("Created");

Headers

ctx.set_header("X-Custom", "value");
ctx.set_header("Cache-Control", "no-cache");

Redirect

ctx.redirect(302, "/new-location");
ctx.redirect(301, "/moved-permanently");

Binary Data

ctx.data("application/octet-stream", data);

HTML

ctx.html("<h1>Hello</h1>");

Cookies

Get Cookie

let session = ctx.cookie("session_id");

Set Cookie

ctx.set_cookie("session_id", "abc123");

// With options
ctx.set_cookie_with_options("session_id", "abc123", CookieOptions {
    max_age: 3600,
    http_only: true,
    secure: true,
    path: "/",
});

Middleware Control

Continue Chain

try ctx.next();

Abort Chain

Simply return without calling next():

if (!is_authenticated) {
    ctx.status(401);
    return;
}

Full Example

app.post("/users", func_handler(|ctx| {
    // Validate content type
    let ct = ctx.header("Content-Type") ?? "";
    if (!ct.starts_with("application/json")) {
        ctx.status(415);
        return;
    }

    // Bind JSON
    let user = try ctx.bind_json::<CreateUser>();

    // Process...
    let id = save_user(user);

    // Response
    ctx.status(201);
    ctx.set_header("Location", `/users/${id}`);
    try ctx.json({"id": id});
}));