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Fastro

Fast and simple web application framework for deno.

With near-native perfomance, you can:

  • Manage your routing, middlewares, and dependencies cleanly.
  • Simplifies JSON, HTML, JSX, and SSR initiation.
  • Take advantage of existing Deno objects and methods.

Getting started

Create a main.ts file for deno-cli entry point.

import application from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";

const app = application();

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

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

await app.serve();

Run the app

deno run -A main.ts

alt text

More examples

Custom port

import application from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";

const app = application();

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

await app.serve({ port: 3000 });
deno run -A https://deno.land/x/fastro@v0.56.2/examples/custom_port.ts

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JSON Response

import application from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";

const app = application();

const json = { text: "Hello world" };

app.get("/", () => json);

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

await app.serve();
deno run -A https://deno.land/x/fastro@v0.56.2/examples/json_response_default.ts

alt text

JSON with Native Response

import application from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";

const app = application();

app.get("/", () => {
  const json = { text: "Hello world" };
  return new Response(JSON.stringify(json), {
    status: 200,
    headers: {
      "content-type": "application/json",
    },
  });
});

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

await app.serve();
deno run -A https://deno.land/x/fastro@v0.56.2/examples/response_json_native.ts

alt text

JSON with Fastro Response

import application, { response } from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";

const app = application();

app.get("/", () => {
  return response().json({ text: "Hello world" });
});

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

await app.serve();
deno run -A https://deno.land/x/fastro@v0.56.2/examples/json_response_fastro.ts

alt text

HTML with Native Response

import application from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";

const app = application();

app.get("/", () => {
  return new Response("<html> Hello world </html>", {
    status: 200,
    headers: {
      "content-type": "text/html",
    },
  });
});

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

await app.serve();
deno run -A https://deno.land/x/fastro@v0.56.2/examples/html_response_native.ts

alt text

HTML with Fastro Response

import application, { response } from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";

const app = application();

app.get("/", () => response().html("<h2>Hello world</h2"));

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

await app.serve();
deno run -A https://deno.land/x/fastro@v0.56.2/examples/html_response_fastro.ts

alt text

HTML with React JSX

import application from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";

const app = application();

app.get("/", () => <h1>Hello world</h1>);

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

await app.serve();

tsconfig: deno.json

{
  "compilerOptions": {
    "strict": true,
    "jsx": "react-jsx",
    "jsxImportSource": "https://esm.sh/react"
  }
}
deno run -A --config deno.json https://deno.land/x/fastro@v0.56.2/examples/html_response_jsx.tsx

Send Custom HTTP Status, Content Type, and Authorization

import application, { response } from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";

const app = application();

app.get("/", () => {
  return response()
    .contentType("application/json")
    .authorization("Basic YWxhZGRpbjpvcGVuc2VzYW1l")
    .status(200)
    .send(JSON.stringify({ message: "Hello world" }));
});

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

await app.serve();
deno run -A https://deno.land/x/fastro@v0.56.2/examples/response_status.ts

alt text

import {
  Cookie,
  deleteCookie,
  getCookies,
  setCookie,
} from "https://deno.land/std@0.133.0/http/cookie.ts"

import application from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";


const app = application();

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

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

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

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

app.get("/check", (req: Request) => {
  const cookie = getCookies(req.headers);
  return new Response(JSON.stringify(cookie));
});

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

await app.serve();
deno run -A https://deno.land/x/fastro@v0.56.2/examples/cookies_native.ts

alt text

import application, {
  Cookie,
  getCookies,
  response,
} from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";

const app = application();

app.get("/set", () => {
  const cookie: Cookie = { name: "Space", value: "Cat" };
  return response()
    .setCookie(cookie)
    .send(JSON.stringify(cookie));
});

app.get("/delete", () => {
  return response()
    .deleteCookie("Space")
    .send("Cookie deleted");
});

app.get("/check", (req: Request) => {
  const cookie = getCookies(req.headers);
  return response().send(JSON.stringify(cookie));
});

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

await app.serve();
deno run -A https://deno.land/x/fastro@v0.56.2/examples/cookies_fastro.ts

alt text

HTML Render with Eta Template Engine

import application from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";import { render } from "https://deno.land/x/eta@1.12.3/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://deno.land/x/fastro@v0.56.2/examples/html_render.ts

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Routing

import application from "https://deno.land/x/fastro@v0.56.2/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://deno.land/x/fastro@v0.56.2/examples/routing.ts

alt text

Route parameters

import application, {
  getParam,
  getParams,
} from "https://deno.land/x/fastro@v0.56.2/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://deno.land/x/fastro@v0.56.2/examples/route_params.ts

alt text

Router Middleware

import application, {
  ConnInfo,
  Next,
  router,
} from "https://deno.land/x/fastro@v0.56.2/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://deno.land/x/fastro@v0.56.2/examples/router_middleware.ts

alt text

Router Middleware with Array

import application, {
  ConnInfo,
  Next,
  router,
} from "https://deno.land/x/fastro@v0.56.2/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://deno.land/x/fastro@v0.56.2/examples/router_middleware_with_array.ts

alt text

Application Level Middleware

import application, {
  ConnInfo,
  Next,
} from "https://deno.land/x/fastro@v0.56.2/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://deno.land/x/fastro@v0.56.2/examples/application_level_middleware.ts

alt text

Application Level Middleware with Array

import application, {
  ConnInfo,
  Next,
} from "https://deno.land/x/fastro@v0.56.2/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://deno.land/x/fastro@v0.56.2/examples/application_level_middleware_with_array.ts

alt text

Route Level Middleware

import application, {
  ConnInfo,
  Next,
} from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";

const app = application();

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

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

await app.serve();
deno run -A https://deno.land/x/fastro@v0.56.2/examples/route_level_middleware.ts

alt text

Route Level Middleware with Array

import application, {
  ConnInfo,
  Next,
} from "https://deno.land/x/fastro@v0.56.2/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://deno.land/x/fastro@v0.56.2/examples/route_level_middleware_with_array.ts

alt text

SQLite and Dependency Injection

import application, { dependency } from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";
const app = application();
const db = new DB("test.db");

const deps = dependency();
deps.set("hello", () => "Hello world");
deps.set("db", db);
app.use(deps);

app.get("/", () => {
  type FunctionType = () => string;
  const fn = <FunctionType> app.getDeps("hello");
  return new Response(fn());
});

app.post("/name", () => {
  const db = <DB> app.getDeps("db");
  db.query(`CREATE TABLE IF NOT EXISTS people (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    name TEXT)`);

  const names = ["Peter Parker", "Clark Kent", "Bruce Wayne"];
  for (const name of names) {
    db.query("INSERT INTO people (name) VALUES (?)", [name]);
  }

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

app.get("/name", () => {
  const db = <DB> app.getDeps("db");
  const res = db.query("SELECT name FROM people");
  return new Response(JSON.stringify(res));
});

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

await app.serve();
deno run -A https://deno.land/x/fastro@v0.56.2/examples/deps_injection.ts

alt text

HTML Render with SSR

Component

Create react component: app.tsx

import React from "https://esm.sh/react@17.0.2";

const App = () => {
  const [count, setCount] = React.useState(0);

  return (
    <div>
      <h1>Hello Deno Land!</h1>
      <button onClick={() => setCount(count + 1)}>Click the 🦕</button>
      <p>You clicked the 🦕 {count} times</p>
    </div>
  );
};

export default App;

SSR Hydration

It is used to hydrate a container whose HTML contents were rendered by ReactDOMServer. React will attempt to attach event listeners to the existing markup.

See: hydrate.

Create react hydration: hydrate.tsx.

import React from "https://esm.sh/react@17.0.2";
import ReactDOM from "https://esm.sh/react-dom@17.0.2";
import App from "./app.tsx";

ReactDOM.hydrate(
  <App />,
  //@ts-ignore:
  document.getElementById("root"),
);

Endpoint

Create routing file: api.tsx

import application, { response } from "https://deno.land/x/fastro@v0.56.2/server/mod.ts";
import render from "https://deno.land/x/fastro@v0.56.2/server/ssr.ts";
import App from "./app.tsx";

const app = application();
const ssr = render()
  .component(<App />)
  .title("Hello world")
  .hydrate("./hydrate.tsx");

app.get("/", () => {
  return response(ssr).render();
});

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

await app.serve();

Configuration

tsconfig: deno.json

{
  "compilerOptions": {
    "strict": true,
    "jsx": "react-jsx",
    "jsxImportSource": "https://esm.sh/react"
  }
}

How to run locally

deno run -A --unstable api.tsx