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Fastro

Fast and simple web application framework with native Deno Request and Response.

You can use the built-in functions and objects that are already available according to your needs – such as all the Request properties, headers, cookies, and more.

Getting started

import application from "https://fastro.dev/server/mod.ts";

const app = application();

app.get("/", () => new Response("Hello world"));

console.log("Listening on: http://localhost:8000");

await app.serve();
deno run -A https://fastro.dev/examples/main.ts

Custom port

import application from "https://fastro.dev/server/mod.ts";

const app = application();

app.get("/", () => new Response("Hello world!"));

await app.serve({ port: 3000 });
deno run -A https://fastro.dev/examples/custom_port.ts

Render with ETA template engine

import application from "https://fastro.dev/server/mod.ts";
import { render } from "https://deno.land/x/eta@v1.12.3/mod.ts";

const app = application();

const headers = new Headers();
headers.set("Content-Type", "text/html; charset=UTF-8");

app.get("/", () => {
  const html = <string> render(
    "<h4>The answer to everything is <%= it.answer %></h4>",
    {
      answer: 42,
    },
  );

  return new Response(html, { headers });
});

console.log("Listening on: http://localhost:8000");

app.serve();
deno run -A https://fastro.dev/examples/render.ts
import application, {
  Cookie,
  deleteCookie,
  getCookies,
  setCookie,
} from "https://fastro.dev/server/mod.ts";

const app = application();

app.post("/", () => {
  const headers = new Headers();
  const cookie: Cookie = { name: "Space", value: "Cat" };
  setCookie(headers, cookie);

  return new Response(JSON.stringify(cookie), { headers });
});

app.get("/", (req: Request) => {
  const headers = req.headers;
  const cookies = getCookies(headers);

  return new Response(JSON.stringify(cookies));
});

app.delete("/", () => {
  const headers = new Headers();
  deleteCookie(headers, "Space");
  const cookies = getCookies(headers);

  return new Response(JSON.stringify(cookies), {
    headers,
  });
});

console.log("Listening on: http://localhost:8000");

app.serve();
deno run -A https://fastro.dev/examples/cookies.ts

Routing

import application from "https://fastro.dev/server/mod.ts";

const app = application();

app.get("/abcd", () => new Response("/abcd"));

app.get("/ef?gh", () => new Response("/ef?gh"));

app.get("/ij+kl", () => new Response("/ij+kl"));

app.get("/mn*op", () => new Response("mn*op"));

app.get("/qr(st)?u", () => new Response("qr(st)?u"));

app.get(/v/, () => new Response("/v/"));

app.get(/.*fast$/, () => new Response("/.*fast$/"));

await app.serve();
deno run -A https://fastro.dev/examples/routing.ts

Route parameters

import application, {
  getParam,
  getParams,
} from "https://fastro.dev/server/mod.ts";

const app = application();

app.get("/:id/user/:name", (req: Request) => {
  const params = getParams(req);
  return new Response(JSON.stringify({ params }));
});

app.get("/post/:id", (req: Request) => {
  const param = getParam("id", req);
  return new Response(param);
});

await app.serve();
deno run -A https://fastro.dev/examples/route_params.ts

Router Middleware

import application, {
  ConnInfo,
  Next,
  router,
} from "https://fastro.dev/server/mod.ts";

const app = application();
const r = router();
const middleware = (_req: Request, _connInfo: ConnInfo, next: Next) => {
  console.log("v2 - 1");
  next();
};

r.get("/", () => new Response("Get"))
  .post("/", () => new Response("Post"))
  .put("/", () => new Response("Put"))
  .delete("/", () => new Response("Delete"));

app.use("/v1", r);
app.use("/v2", middleware, r);

await app.serve();
deno run -A https://fastro.dev/examples/router_middleware.ts

Router Middleware with Array

import application, {
  ConnInfo,
  Next,
  router,
} from "https://fastro.dev/server/mod.ts";

const app = application();
const r = router();
const middlewares = [(_req: Request, _connInfo: ConnInfo, next: Next) => {
  console.log("v2 - 1");
  next();
}, (_req: Request, _connInfo: ConnInfo, next: Next) => {
  console.log("v2 - 2");
  next();
}];

r.get("/", () => new Response("Get"))
  .post("/", () => new Response("Post"))
  .put("/", () => new Response("Put"))
  .delete("/", () => new Response("Delete"));

app.use("/v1", r);
app.use("/v2", middlewares, r);

await app.serve();
deno run -A https://fastro.dev/examples/router_middleware_with_array.ts

Application Level Middleware

import application, { ConnInfo, Next } from "https://fastro.dev/server/mod.ts";

const app = application();

app.use((_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("app middleware #1");
  next();
});

app.use((_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("app middleware #2");
  next();
});

app.use((_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("app middleware #3");
  next();
}, (_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("app middleware #4");
  next();
});

app.get("/", () => new Response("App level #1"));

await app.serve();
deno run -A https://fastro.dev/examples/application_level_middleware.ts

Application Level Middleware with Array

import application, { ConnInfo, Next } from "https://fastro.dev/server/mod.ts";

const app = application();

const middlewares = [(_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("middleware #1");
  next();
}, (_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("middleware #2");
  next();
}, (_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("middleware #3");
  next();
}, (_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("middleware #4");
  next();
}];

app.use(middlewares);

app.get("/", () => new Response("App level #1"));

await app.serve();
deno run -A https://fastro.dev/examples/application_level_middleware_with_array.ts

Route Level Middleware

import application, { ConnInfo, Next } from "https://fastro.dev/server/mod.ts";

const app = application();

app.use((_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("app middleware #1");
  next();
});

app.use((_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("app middleware #2");
  next();
});

app.use((_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("app middleware #3");
  next();
}, (_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("app middleware #4");
  next();
});

app.get("/", () => new Response("App level #1"));

await app.serve();
deno run -A https://fastro.dev/examples/route_level_middleware.ts

Route Level Middleware with Array

import application, { ConnInfo, Next } from "https://fastro.dev/server/mod.ts";

const app = application();

const middlewares = [(_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("middleware #1");
  next();
}, (_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("middleware #2");
  next();
}, (_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("middleware #3");
  next();
}, (_req: Request, _conn: ConnInfo, next: Next) => {
  console.log("middleware #4");
  next();
}];

app.get("/mnop", middlewares, () => new Response("Route level middleware #3"));

await app.serve();
deno run -A https://fastro.dev/examples/route_level_middleware_with_array.ts