# Getting started

## Installation

**Marble.js** requires node **v8.0** or higher:

```bash
$ npm i @marblejs/core @marblejs/middleware-logger @marblejs/middleware-body rxjs
```

or if you are a hipster:

```bash
$ yarn add @marblejs/core @marblejs/middleware-logger @marblejs/middleware-body rxjs
```

## Bootstrapping

The very basic configuration consists of two steps: *HTTP listener* definition and *HTTP server* configuration.

`httpListener` is the basic starting point of every Marble application. It includes definitions of all *middlewares* and API *effects*.

{% code title="http.listener.ts" %}

```typescript
import { httpListener } from '@marblejs/core';
import { logger$ } from '@marblejs/middleware-logger';
import { bodyParser$ } from '@marblejs/middleware-body';
import { api$ } from './api.effects';

const middlewares = [
  logger$(),
  bodyParser$(),
  // ...
];

const effects = [
  api$,
  // endpoint2$
  // ...
];

export default httpListener({ middlewares, effects });
```

{% endcode %}

And here is our simple "hello world" endpoint.

{% code title="api.effects.ts" %}

```typescript
import { r } from '@marblejs/core';
import { mapTo } from 'rxjs/operators';

export const api$ = r.pipe(
  r.matchPath('/'),
  r.matchType('GET'),
  r.useEffect(req$ => req$.pipe(
     mapTo({ body: 'Hello, world!' }),
  )));
```

{% endcode %}

To create Marble app instance, we can use [`createServer`](https://marblejs.gitbook.io/docs/v2/api-reference/core/createserver), which is a wrapper around Node.js server creator with much more possibilities and goods inside. When created, it won't automatically start listening to given port and hostname until you call `.run()` method on it.

{% code title="server.ts" %}

```typescript
import { createServer } from '@marblejs/core';
import httpListener from './http.listener';

export const server = createServer({
  port: 1337,
  hostname: '127.0.0.1',
  httpListener,
});

server.run();
```

{% endcode %}

{% hint style="info" %}
you can always visit [example repository](https://github.com/marblejs/example) for a complete Marble.js app example.
{% endhint %}

We'll use [TypeScript](https://www.typescriptlang.org/) in the documentation but you can always write Marble apps in standard JavaScript (and any other language that transpiles to JavaScript).

To test run your server you can install `typescript` compiler and `ts-node`:

```bash
$ yarn add typescript ts-node
```

then add the following script to your `package.json` file:

```javascript
"scripts": {
  "start": "ts-node server.ts"
}
```

Now go ahead, create `server.ts`, `http.listener.ts`, `api.effects.ts` modules in your project and run your server:

```bash
$ yarn start
```

finally test your "functional" server by visiting [http://localhost:1337](https://marblejs.gitbook.io/docs/v2/overview/getting-started)

{% hint style="info" %}
For more API specific details about server bootstraping, visit [createServer](https://marblejs.gitbook.io/docs/v2/api-reference/core/createserver) API reference.
{% endhint %}

If you prefer to have standard Node.js control over server creation, you can also easily hook the app directly into Node.js `http.createServer`

{% code title="server.ts" %}

```typescript
import { createContext } from '@marblejs/core';
import * as http from 'http';
import httpListener from './http.listener';

const httpServer = httpListener
  .run(createContext());

export const server = http
  .createServer(httpServer)
  .listen(1337, '127.0.0.1');
```

{% endcode %}

In the next chapter you will learn how to create basic **Marble.js** endpoints using [Effects](https://marblejs.gitbook.io/docs/v2/overview/effects).