🦕 Serva

The zero setup web framework for Deno. Convention > Configuration, focus on building your app, let Serva do the REST.

Define a route

// ./routes/index.ts
export default () => "Hello, World!";

Start your app

$ serva start

Simple

$ curl localhost:4500
Hello, World!

App directory

Serva requires your app to have a strict file system layout. Currently Serva can only read routes, however in future releases the directory will become very opinionated.

Serva will run on any directory. It will look for a routes directory to read and a serva.config.json for any low-level config (port, hostnames, etc.).

Routes

All routes live inside the routes directory. They are a mirrored representation of your app’s endpoints. Lets look at an example directory of the Serva package.

$ tree ./example
example
├── routes
│   ├── index.get.ts
│   ├── index.post.ts
│   └── profile
│       └── [name].get.ts
└── serva.config.json

2 directories, 4 files

Without reading a single line of code you can see the available routes your app will serve. A GET and a POST route on the root path, /. A single route is defined per file. There can be no fall-through routes. This gives a clear and transparent overview of any app, no mater who/where/when/how it was developed.

Methods

Routes can be suffixed with a HTTP method to signal that the route should only be handled by requests that match that method. As you can see from the example directory they are .get and .post. Serva allows the following methods, however can be configured to accept more, see Method suffix.

Any method

If the method suffix is omitted, Serva will bind any/all methods to that route. Serva will first try to match any defined methods before using an any route.

Parameters

Routes can contain parameters within their path. Parameters are a way to bind segments of the path to the request params map. Use square brackets around the name of a parameter within the filename.

$ mkdir ./example/routes/profile
$ touch ./example/routes/profile/[name].get.ts

// ./example/routes/profile/[name].get.ts
import { ServaRequest } from "https://serva.land/serva/mod.ts";

export default ({ params }: ServaRequest) => `Welcome ${params.get("name"}.`;

$ curl localhost:4500/profile/chris
Welcome chris.

Callbacks

Each route must contain a default export as a function. This function is known as the route callback. When Serva matches a route it will invoke this callback with the request.

// ./example/routes/index.get.ts
import { ServaRequest } from "https://serva.land/serva/mod.ts";

export default ({ response }: ServaRequest) => {
  response.headers = new Headers({
    "X-Powered-By": "Serva",
  });

  return "Hello from Serva.";
};

Requests

Serva has it’s own request object to preserve the HTTP request object from Deno’s std library. The request object is similar and if you need/require the HTTP version of the object it is also accessible.

interface ServaRequest {
  // std http request
  readonly httpRequest: http.ServerRequest;

  // request
  readonly url: URL;
  readonly method: string;
  readonly params: ReadonlyMap<string, string>;
  readonly headers: Headers;

  // response
  readonly response: http.Response;
}

Responses

Serva exposes a single response object that you can manipulate within your route.

// ./example/routes/index.get.ts
import { ServaRequest } from "https://serva.land/serva/mod.ts";

export default ({ response }: ServaRequest) => {
  // set headers
  response.headers = new Headers({
    "X-Powered-By": "Serva",
  });

  // set status
  response.status = 401;

  // set trailers
  response.trailers = () =>
    new Headers({
      "X-Watch-Me": "https://youtu.be/dQw4w9WgXcQ",
    });

  // return to set the body
  return "Hello from Serva.";
};

Config

When Serva reads a serva.config.json file from the application root it will use this to configure the app. You can set the following options within the file:

interface ServaConfig {
  port: number;
  hostname?: string;
  extension: string;
  methods: string[];
}

Extension

By default Serva will read files with .ts file extensions. If you prefer to write your application in JavaScript you can set this to .mjs or .js.

Method suffixes

By default Serva will only bind the available methods (see Methods). Set this if you wish to control the method suffixes of your application.

// ./example/serva.config.json
{
  methods: [
    "get",
    "head",
    "post",
    "put",
    "delete",
    "options",
    "trace",
    "patch",
  ],
}

Running

Serva does not export any application interface. Instead it uses a main import to instantiate and run an app. To start an application is easy, just tell the app file to start with a few permissions.

$ deno run --allow-read --allow-net https://serva.land/serva/app.ts start

Serva requires the following Deno flags to start:

Installation

Alternatively you can install Serva as a Deno binary. If you have configured Deno correctly you will be able to use the serva alias to start an application.

$ deno install --name serva --allow-read --allow-net https://serva.land/serva/app.ts
$ serva start

Philosophy

Serva was built to let developers focus on what really matters, the application. Many Node.js frameworks allow developers to setup servers 1001 different ways. Through-out developing and maintaining Node.js apps, each one looks slightly different and you can become lost in how the original developer decided to setup on that day. Let the framework worry about this setup and make Deno apps consistent, let’s not fall into the same pattern.

1. Use the filesystem.
2. Zero interface.

Roadmap

• ✅ Routes
• 🏗️ Hooks (middleware)
• 🗓️ Services
• 🗓️ Configuration
• 🗓️ CLI
• 🗓️ Explorer

Key

🗓️ planned
🏗️ development
✅ done