How do I use the "version" property in package.json as the app's directory in grunt? - node.js

Question

I'm managing a project written in angularjs, with the default directory structure, excluding the app directory which uses versioning (ie. "app/0.0.0/", "app/0.1.0/" etc..).
I'm trying to use grunt's package.json file's "version" property to load the correct
directory so I won't have to manually change the app path in gruntfile.js
but for some reason I keep getting "Cannot GET /" when I run "grunt server".
To better explain this, here's a sample of my gruntfile.js:
var yeomanConfig = {
app: 'app/<% pkg.version %>/',
dist: 'dist'
...
grunt.initConfig({
yeoman: yeomanConfig,
pkg: grunt.file.readJSON('package.json'),
...
If I manually change the app property to "app/0.0.0" it works like a charm
so I'm guessing this has something to do with the templating.
Any ideas?
Thank you very much for the help.
Edit: Thank you for the correction Andreas and Matjaz, but this doesn't solve the problem and gives the same error...
This solves the problem for me but without the templating system:
var pkgVersion = grunt.file.readJSON('package.json').version;
// configurable paths
var yeomanConfig = {
app: 'app/'+pkgVersion,
dist: 'dist'
};
It's pretty ugly but it works. Hoping for a proper solution.

Answer 1

The best way to handle above scenario is that, In the grunt.initConfig define the package.json
grunt.initConfig({
pkg: grunt.file.readJSON("package.json")
})
Once above initialized you can use the properties of the package.json throughout the grunt.js file.
<%= pkg.version %>
<%= pkg.homepage %>

Answer 2

To echo data use <%=:
<%= pkg.version %>

Answer 3

I extend the appConfig with the name and version:
var appConfig = {
app: require('./bower.json').appPath || 'app',
name: require('./package.json').name || 'angularapp',
version: require('./package.json').version || '1.0.0',
dist: 'dist'
};
Then you can access the variables like this:
<%= yeoman.name %>
<%= yeoman.version %>
For me a clean solution with an optional fallback.