var httpServerFactory = require( '@stdlib/net/http-server' );

Returns a function to create an HTTP server.

var httpServer = httpServerFactory();

The function supports the following parameters:

• options: options (optional).
• requestListener: callback to invoke upon receiving an HTTP request (optional).

To bind a request callback to a server, provide a requestListener.

function requestListener( request, response ) {
    console.log( request.url );
    response.end( 'OK' );
}

var httpServer = httpServerFactory( requestListener );

In addition to the options supported by http.createServer, the function accepts the following options:

• port: server port. Default: 0 (i.e., randomly assigned).
• maxport: max server port when port hunting. Default: maxport=port.
• hostname: server hostname.
• address: server address. Default: 127.0.0.1.

To specify server options, provide an options object.

var opts = {
    'port': 7331,
    'address': '0.0.0.0'
};

var httpServer = httpServerFactory( opts );

To specify a range of permissible ports, set the maxport option.

var opts = {
    'maxport': 9999
};

var httpServer = httpServerFactory( opts );

When provided a maxport option, a created server will search for the first available port on which to listen, starting from port.

Creates an HTTP server.

function done( error, server ) {
    if ( error ) {
        throw error;
    }
    console.log( 'Success!' );
    server.close();
}

var httpServer = httpServerFactory();

httpServer( done );

The function supports the following parameters:

• done: callback to invoke once a server is listening and ready to handle requests.

• Which server options are supported depends on the Node.js version. Older Node.js versions (e.g., <= v8.12.0) do not support an options object when calling http.createServer, and, for those versions, any options supported by http.createServer in later Node.js versions are ignored.
• Port hunting can be useful in a microservice deployment. When a port is randomly assigned (options.port=0), if a server fails and is restarted, the server is unlikely to bind to its previous port. By allowing a constrained search, assuming no lower ports within a specified range have freed up in the meantime, the likelihood of listening on the same port is increased. A server can typically restart and bind to the same port faster than binding to a new port and re-registering with a microservice registry, thus minimizing possible service interruption and downtime.