Grunt usemin, get final path of compressed files to allow preload - angularjs

Question

I have a HTML block like this for minify css and js files:
<!-- build:css static/assets/css/combined.css -->
<link rel="stylesheet" href="static/bower_components/font-awesome/css/font-awesome.css">
<link rel="stylesheet" href="static/bower_components/photoswipe/dist/photoswipe.css" />
<link rel="stylesheet" href="static/bower_components/photoswipe/dist/default-skin/default-skin.css" />
<link rel="stylesheet" href="static/assets/css/jasny-bootstrap.min.css">
<link rel="stylesheet" href="static/assets/css/main.min.css">
<link rel="stylesheet" href="static/assets/css/custom.css">
<link rel="stylesheet" href="static/common/da-angular-spinkit/angular-spinkit.min.css">
<!-- endbuild -->
I need to make a preload of the resource static/assets/css/combined.css but the final file has a hash at the end of its name, so the final path is like static/assets/css/combined.min-af5890ce41.css, so I don't know how to include the following tag:
<link rel="preload" href="static/assets/css/combined.min-af5890ce41.css"/>
-------------------------------------------^^^^^^^^^^^^^^^^^^^^^^^^^^^
Because I don't know what is the final name of the generated minified file.
How can I get the output of this generated file? I only need the final path name. I search about grunt-usemin but seems to be "minimalist".
Thank you.
EDIT
I found on the project some pieces of grunt code if you can see what module is acting on the file hashes:
/client/static/bower_components/bootstrap/Gruntfile.js:
Here I can see:
jshint
uglify
less
csslint
cssmin
csscomb
htmlmin
I can't see what of this modules acts on the build:js or build:css in the index.html.
/client/static/bower_components/photoswipe/Gruntfile.js:
Here I can see npm tasks:
grunt.loadNpmTasks('grunt-contrib-clean');
grunt.loadNpmTasks('grunt-contrib-concat');
grunt.loadNpmTasks('grunt-contrib-uglify');
grunt.loadNpmTasks('grunt-contrib-jshint');
grunt.loadNpmTasks('grunt-contrib-watch');
grunt.loadNpmTasks('grunt-sass');
grunt.loadNpmTasks('grunt-autoprefixer');
grunt.loadNpmTasks('grunt-contrib-copy');
grunt.loadNpmTasks('grunt-jekyll');
grunt.loadNpmTasks('grunt-contrib-cssmin');
grunt.loadNpmTasks('grunt-aws-s3');
grunt.loadNpmTasks('grunt-svgmin');
EDIT 2
On the folder /dev/ there is a gruntfile.js with this code (it seems not related):
var src = "../src/client/";
module.exports = function (grunt) {
grunt.loadNpmTasks("grunt-angular-gettext");
// We extract translations with 'grunt nggettext_extract'. Those files go to '/dev/translations-extract' directory.
grunt.initConfig({
nggettext_extract: {
pot: {
files: {
'translations-extract/template.pot': [src + 'static/common/**/*.html', src + 'static/states/**/*.html', src + 'index.html', src + 'indexMobile.html']
}
},
},
// We compile those files (*.po) with 'grunt nggettext_compile. The translations.js file goes to /client/static/util/translations/ dir.
nggettext_compile: {
all: {
options: {
module: 'alvarez',
},
files: {
'../src/client/static/common/translations/translations.js': ['translations-extract/*.po']
}
},
},
})
}
And then, on /dev/bower_components/ there are tons of plugins, each one with its gruntfile.js inside.
EDIT 3
Found on /ops/ a gulpfile.js and seems to be related
/**
* Crea una versión de distribución concatenada y minificada
*/
var gulp = require('gulp');
var run = require('gulp-run');
var gulpif = require('gulp-if');
var useref = require('gulp-useref');
var uglify = require('gulp-uglify');
var rename = require('gulp-rename');
var debug = require('gulp-debug');
var del = require('del');
var ngAnnotate = require('gulp-ng-annotate');
var minifyHTML = require('gulp-minify-html');
var cleanCSS = require('gulp-clean-css');
var rev = require('gulp-rev');
var revReplace = require('gulp-rev-replace');
var embedTemplates = require('./embed-templates/index.js');
var dist = './dist/';
var indexDist = dist + 'client/';
var HTMLDist = indexDist + 'static/';
var src = '../src/';
var assetsSrc = src + 'client/static/assets/'
var cssSrc = assetsSrc + 'css/';
var serverDist = dist + 'server/';
var libDist = dist + 'lib/';
// pm2
// Init-dist
gulp.task('pm2', function () {
run('pm2 start ' + serverDist + 'alvarez.js').exec();
});
// Init-stop
gulp.task('pm2-stop', function () {
run('pm2 stop ' + serverDist + 'alvarez.js').exec();
});
//Init-restart
gulp.task('pm2-restart', function () {
run('pm2 restart ' + serverDist + 'alvarez.js').exec();
});
// npm-install on dist
gulp.task('npm-install-dist', function () {
run('npm install --production --prefix ' + serverDist).exec();
})
// Dist subtasks
// Cleaning dist
gulp.task('del-dist', function () {
del(dist, {
force: true
}, console.log('Files deleted'));
});
// Moving index.js
gulp.task('move-server-js', function () {
return gulp.src([src + 'server/alvarez.js', src + 'server/package.json'])
.pipe(gulp.dest(serverDist));
});
gulp.task('move-config-js', function () {
return gulp.src([src + 'server/lib/**/*.js'])
.pipe(gulp.dest(serverDist + 'lib/'))
})
//gulp.task('move-lib-js', function () {
// return gulp.src(src + 'lib/config.js')
// .pipe(gulp.dest(libDist));
//});
//
//gulp.task('move-boot-pro', function () {
// return gulp.src(src + 'lib/boot.pro.js')
// .pipe(rename('boot.js'))
// .pipe(gulp.dest(libDist));
//})
// Moving html
gulp.task('move-html', function () {
var opts = {
empty: true
};
return gulp.src([src + 'client/static/**/**/*.html', src + 'client/static/**/**/*.swf'])
.pipe(minifyHTML(opts))
.pipe(gulp.dest(HTMLDist));
});
gulp.task('minify-css', ['move-assets', 'move-html-index', 'move-html-index-mobile'], function() {
return gulp.src(HTMLDist + 'assets/css/*.css')
.pipe(cleanCSS())
.pipe(gulp.dest(HTMLDist + 'assets/css/'));
})
gulp.task('move-assets', function () {
return gulp.src(src + '/client/static/assets/**/*.*')
.pipe(gulp.dest(HTMLDist + 'assets/'));
});
// Moving html index
gulp.task('move-html-index', function () {
var assets = useref.assets();
//.pipe(gulpif('**\/da-*.js', embedTemplates()))
return gulp.src(src + 'client/index.html')
.pipe(assets)
.pipe(gulpif('*.js', embedTemplates()))
.pipe(gulpif('.*\.js', ngAnnotate()))
.pipe(gulpif('.*\.js', uglify()))
.pipe(rev())
.pipe(assets.restore())
.pipe(useref())
.pipe(revReplace())
.pipe(debug())
.pipe(gulp.dest(indexDist));
});
gulp.task('move-html-index-mobile', function () {
var assets = useref.assets();
return gulp.src(src + 'client/indexMobile.html')
.pipe(assets)
.pipe(gulpif('*.js', embedTemplates()))
.pipe(gulpif('.*\.js', ngAnnotate()))
.pipe(gulpif('.*\.js', uglify()))
.pipe(assets.restore())
.pipe(useref())
.pipe(gulp.dest(indexDist));
})
gulp.task('embed-templates', [], function () {
return gulp.src([src + 'client/static/states/**/da*/*.js', src + 'client/static/common/**/da*/*.js'])
.pipe(gulpif('*.js', embedTemplates()))
.pipe(ngAnnotate())
.pipe(uglify())
.pipe(gulp.dest(indexDist))
});
// Build dist task
gulp.task('build-dist', ['move-html', 'move-server-js', 'move-config-js', 'minify-css'], function () {
console.log('Dist ready...');
});

Answer 1

The answer is no in grunt-usemin, but in one of the dependencies: grunt-filerev. This last module is the one used to create the file revisions of you css, js and other files.
After grunt-filerev is executed (executed as a subtask of grunt-usemin), it creates a summary (stored in within your grunt task, under grunt.filerev.summary). The summary contains the following information:
{
“original.js” : “destination.59bcc35a.js”
}
So you could use it later on you string replacement method/module of your choice.
You can find more information about grunt-filerev here.
Hope it helps.