Gulp - SVGs sprite generator - include content into html

gulp.svg.js

// Combine svg files and inject it into index.html
gulp.task('svg', () => {
    var svgs = gulp
        .src('app/images/svg/*.svg')
        .pipe($.svgmin())
        .pipe($.svgstore({ inlineSvg: true }));

    function fileContents (filePath, file) {
        return file.contents.toString();
    }

    return gulp
        .src('app/index.html')
        .pipe($.inject(svgs, { transform: fileContents }))
        .pipe(gulp.dest('app'));
});