Add data gulp task.

This adds a new Gulp task to automatically include `app/data` in
dev builds if it exists. This directory will contain sample data
files for use during development and outputs them to `build/data`.
Additionally, this integrates with browser-sync and will
automatically reload open browsers as testing datasets are
changed.

Change-Id: Ie1578682d11e36bd6142b9d326f50a547aa4613b

.gitignore

@@ -4,6 +4,7 @@ stackviz/static/components/*
 node_modules
 build
 app/js/templates.js
+app/data
 *.py[cod]
 
 # C extensions

gulp/config.js

@@ -55,6 +55,11 @@ module.exports = {
   'test': {
     'karma': 'test/karma.conf.js',
     'protractor': 'test/protractor.conf.js'
+  },
+
+  'data': {
+    'src' : ['app/data/**/*'],
+    'dest': 'build/data'
   }
 
 };

gulp/tasks/data.js

@@ -0,0 +1,15 @@
+'use strict';
+
+var config      = require('../config');
+var changed     = require('gulp-changed');
+var gulp        = require('gulp');
+var browserSync = require('browser-sync');
+
+gulp.task('data', function() {
+
+  return gulp.src(config.data.src)
+    .pipe(changed(config.data.dest))
+    .pipe(gulp.dest(config.data.dest))
+    .pipe(browserSync.reload({ stream: true, once: true }));
+
+});

gulp/tasks/development.js

@@ -9,6 +9,6 @@ gulp.task('dev', ['clean'], function(cb) {
 
   global.isProd = false;
 
-  runSequence(['styles', 'images', 'fonts', 'views', 'browserify'], 'watch', cb);
+  runSequence(['styles', 'images', 'fonts', 'data', 'views', 'browserify'], 'watch', cb);
 
-});
+});

gulp/tasks/watch.js

@@ -10,6 +10,7 @@ gulp.task('watch', ['browserSync', 'server'], function() {
   gulp.watch(config.styles.src,  ['styles']);
   gulp.watch(config.images.src,  ['images']);
   gulp.watch(config.fonts.src,   ['fonts']);
+  gulp.watch(config.data.src,    ['data']);
   gulp.watch(config.views.watch, ['views']);
 
-});
+});