deviserve

deviserve is a node.js package that analyses the user agent of the browser and gives information about device type (desktop, tablet or phone).

Using sessions

If you are using express-session middleware, the information about device is stored as a session variable to avoid re-analyzing the user agent and lose precious machine cycles, which make it suitable for big multi-device applications.

var expressSession = require('express-session');

app.use( expressSession({secret:'mySecretKey', cookie: { maxAge: 60000 }, resave:false, saveUninitialized:true}) );

The deviserve offers a middleware that serves static files from different directories depending on the device.

Middleware

The deviserve middleware serves static files from different directories depending on the device.

var deviserve = require("deviserve");
var Deviserve = deviserve()
    .path( __dirname+"/public/" )
    .on(".htm",renderJade)
    .on(".jade":page404);

function renderJade(req, res, filename){
    filename = filename.slice(0,-4)+".jade";
    require("jade").renderFile(filename , function(err,html){if (err) {res.send(500);} else {res.send(200,html);}});
}

function page404(req, res, filename){
    res.send(404).end();
}

app.use( "/pub", Deviserve );

The code above permits to serve static files fom different directories when url starting with /pub/... : files are served from /public/desktop/, /public/tablet/ and /public/phone/.

In addition, the url with .htm extension is served from a .jade compiled file and .jade files are excluded from visualisation.

Specific paths

The .path( ) function can receive an object as its first argument. In this case, the specific root directory is specified for each device, as in the example bellow :

var deviserve  = require('deviserve');
var Deviserve = deviserve().path({
    desktop:__dirname+"/views/desktop/",
    tablet:__dirname+"/views/mobile/",
    phone:__dirname+"/views/mobile/"
  });

app.use( "/pub", Deviserve );

In this case, tablets and phones files are served from /moblile/ subdirectory where desktop devices files are served from /desktop/ directory/

Other functions

This package offers one other function named root(). Deviserve.root(req) returns the root directory on the current device :

Deviserve.root(req)

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