STRF-4605: Add resourceHints helper

helpers/getFontLoaderConfig.js

@@ -0,0 +1,11 @@
+'use strict';
+
+const getFonts = require('../lib/fonts');
+
+module.exports = function(paper) {
+    const handlebars = paper.handlebars;
+
+    handlebars.registerHelper('getFontLoaderConfig', function () {
+        return new handlebars.SafeString(JSON.stringify(getFonts(paper, 'webFontLoaderConfig')));
+    });
+};

helpers/getFontsCollection.js

@@ -1,85 +1,11 @@
 'use strict';
 
-var _ = require('lodash');
+const getFonts = require('../lib/fonts');
 
-function helper(paper) {
-    var handlebars = paper.handlebars;
+module.exports = function(paper) {
+    const handlebars = paper.handlebars;
 
     handlebars.registerHelper('getFontsCollection', function () {
-        var fontKeyFormat = new RegExp(/\w+(-\w*)*-font$/),
-            googleFonts = [],
-            linkElements = [];
-
-        _.each(paper.themeSettings, function (value, key) {
-            var split;
-
-            if (fontKeyFormat.test(key)) {
-                split = value.split('_');
-
-                switch (split[0]) {
-                case 'Google':
-                    googleFonts.push(value);
-                    break;
-
-                default:
-                    break;
-                }
-            }
-        });
-
-        linkElements.push(googleParser(googleFonts));
-
-        return new handlebars.SafeString(linkElements.join(''));
-    });
-}
-
-/**
- * Parser for Google fonts
- *
- * @param fonts - Array of fonts that might look like
- * Google_Open+Sans
- * Google_Open+Sans_400
- * Google_Open+Sans_400_sans
- * Google_Open+Sans_400,700_sans
- * Google_Open+Sans_400,700italic
- * Google_Open+Sans_400,700italic_sans
- *
- * @returns {string}
- */
-
-function googleParser(fonts) {
-    var collection = [],
-        familyHash = {};
-
-    _.each(fonts, function fontsIterator(font) {
-        var split = font.split('_'),
-            familyKey = split[1],  // Eg: Open+Sans
-            weights = split[2];    // Eg: 400,700italic
-
-        if (_.isEmpty(familyKey)) {
-            return;
-        }
-
-        if (_.isUndefined(weights)) {
-            weights = '';
-        }
-
-        if (!_.isArray(familyHash[familyKey])) {
-            familyHash[familyKey] = [];
-        }
-
-        weights = weights.split(',');
-
-        familyHash[familyKey].push(weights);
-        familyHash[familyKey] = _.uniq(_.flatten(familyHash[familyKey]));
+        return getFonts(paper, 'linkElements');
     });
-
-
-    _.each(familyHash, function fontHashIterator(weights, family) {
-        collection.push(family + ':' + weights.join(','));
-    });
-
-    return '<link href="//fonts.googleapis.com/css?family=' + collection.join('|') + '" rel="stylesheet">';
-}
-
-module.exports = helper;
+};

helpers/resourceHints.js

@@ -0,0 +1,38 @@
+'use strict';
+
+const _ = require('lodash');
+const getFonts = require('../lib/fonts');
+
+const fontResources = {
+    'Google': [
+        '//ajax.googleapis.com',
+        '//fonts.googleapis.com',
+        '//fonts.gstatic.com',
+    ],
+};
+
+module.exports = function(paper) {
+    paper.handlebars.registerHelper('resourceHints', function() {
+        function format(host) {
+            return `<link rel="dns-prefetch preconnect" href="${host}" crossorigin>`;
+        }
+
+        var hosts = [];
+
+        // Add cdn
+        const cdnUrl = paper.settings['cdn_url'] || '';
+        if (cdnUrl != '') {
+            hosts.push(cdnUrl);
+        }
+
+        // Add font providers
+        const fontProviders = _.keys(getFonts(paper, 'providerLists'));
+        _.each(fontProviders, function(provider) {
+            if (typeof fontResources[provider] !== 'undefined') {
+                hosts = hosts.concat(fontResources[provider]);
+            }
+        });
+
+        return new paper.handlebars.SafeString(_.map(hosts, format).join(''));
+    });
+}

lib/fonts.js

@@ -0,0 +1,134 @@
+'use strict';
+
+const _ = require('lodash');
+const fontKeyFormat = new RegExp(/\w+(-\w*)*-font$/);
+const fontProviders = {
+    'Google': {
+        /**
+         * Parser for Google fonts
+         *
+         * @param {Array} fonts - Array of fonts that might look like
+         * Google_Open+Sans
+         * Google_Open+Sans_400
+         * Google_Open+Sans_400_sans
+         * Google_Open+Sans_400,700_sans
+         * Google_Open+Sans_400,700italic
+         * Google_Open+Sans_400,700italic_sans
+         *
+         * @returns {string}
+         */
+        parser: function(fonts) {
+            var collection = [],
+                familyHash = {};
+
+            _.each(fonts, function fontsIterator(font) {
+                var split = font.split('_'),
+                    familyKey = split[1],  // Eg: Open+Sans
+                    weights = split[2];    // Eg: 400,700italic
+
+                if (_.isEmpty(familyKey)) {
+                    return;
+                }
+
+                if (_.isUndefined(weights)) {
+                    weights = '';
+                }
+
+                if (!_.isArray(familyHash[familyKey])) {
+                    familyHash[familyKey] = [];
+                }
+
+                weights = weights.split(',');
+
+                familyHash[familyKey].push(weights);
+                familyHash[familyKey] = _.uniq(_.flatten(familyHash[familyKey]));
+            });
+
+            _.each(familyHash, function fontHashIterator(weights, family) {
+                collection.push(family + ':' + weights.join(','));
+            });
+
+            return collection;
+        },
+
+        buildLink: function(fonts) {
+            return '<link href="//fonts.googleapis.com/css?family=' + fonts.join('|') + '" rel="stylesheet">';
+        },
+
+        buildFontLoaderConfig: function(fonts) {
+            function replaceSpaces(font) {
+                return font.split('+').join(' ');
+            }
+
+            return {
+                google: {
+                    families: _.map(fonts, replaceSpaces),
+                }
+            };
+        },
+    },
+};
+
+/**
+ * Get collection of fonts used in theme settings.
+ *
+ * @param {Object} paper The paper instance
+ * @param {string} format The desired return value. If format == 'providerLists', return an object with provider names for keys
+ *   and a list of fonts in the provider format as values, suitable for use with Web Font Loader. If format == 'linkElements',
+ *   return a string containing <link> elements to be directly inserted into the page. If format == 'webFontLoaderConfig', return an
+ *   object that can be used to configure Web Font Loader.
+ * @returns {Object.<string, Array>|string}
+ */
+module.exports = function(paper, format) {
+    // Collect font strings from theme settings
+    const collectedFonts = {};
+    _.each(paper.themeSettings, function(value, key) {
+        if (!fontKeyFormat.test(key)) {
+            return;
+        }
+
+        const splits = value.split('_');
+        const provider = splits[0];
+
+        if (typeof fontProviders[provider] === 'undefined') {
+            return;
+        }
+
+        if (typeof collectedFonts[provider] === 'undefined') {
+            collectedFonts[provider] = [];
+        }
+
+        collectedFonts[provider].push(value);
+    });
+
+    // Parse font strings based on provider
+    const parsedFonts = _.mapValues(collectedFonts, function(value, key) {
+        return fontProviders[key].parser(value);
+    });
+
+    // Format output based on requested format
+    switch(format) {
+    case 'linkElements':
+        const formattedFonts = _.mapValues(parsedFonts, function(value, key) {
+            return fontProviders[key].buildLink(value);
+        });
+        return new paper.handlebars.SafeString(_.values(formattedFonts).join(''));
+
+    case 'webFontLoaderConfig':
+        // Build configs
+        const configs = _.mapValues(parsedFonts, function(value, key) {
+            return fontProviders[key].buildFontLoaderConfig(value);
+        });
+
+        // Merge them
+        const fontLoaderConfig = {};
+        _.each(configs, function(config) {
+            return Object.assign(fontLoaderConfig, config);
+        });
+        return fontLoaderConfig;
+
+    case 'providerLists':
+    default:
+        return parsedFonts;
+    }
+}

test/helpers/getFontLoaderConfig.js

@@ -0,0 +1,37 @@
+var Code = require('code'),
+    Lab = require('lab'),
+    Paper = require('../../index'),
+    lab = exports.lab = Lab.script(),
+    describe = lab.experiment,
+    expect = Code.expect,
+    it = lab.it;
+
+function c(template, themeSettings) {
+    return new Paper({}, themeSettings).loadTemplatesSync({template: template}).render('template', {});
+}
+
+describe('getFontLoaderConfig helper', function () {
+    it('should return the expected font url', function (done) {
+        const themeSettings = {
+            'test1-font': 'Google_Open+Sans',
+            'test2-font': 'Google_Open+Sans_400italic',
+            'test3-font': 'Google_Open+Sans_700',
+            'test4-font': 'Google_Karla_700',
+            'test5-font': 'Google_Lora_400_sans',
+            'test6-font': 'Google_Volkron',
+            'test7-font': 'Google_Droid_400,700',
+            'test8-font': 'Google_Crimson+Text_400,700_sans',
+            'random-property': 'not a font'
+        };
+
+        const template = "{{getFontLoaderConfig}}";
+        const expectedConfig = {
+            google: {
+                families: ['Open Sans:,400italic,700', 'Karla:700', 'Lora:400', 'Volkron:', 'Droid:400,700', 'Crimson Text:400,700']
+            }
+        };
+
+        expect(c(template, themeSettings)).to.be.equal(JSON.stringify(expectedConfig));
+        done();
+    });
+});

test/helpers/resourceHints.js

@@ -0,0 +1,33 @@
+var Code = require('code'),
+    Lab = require('lab'),
+    Paper = require('../../index'),
+    lab = exports.lab = Lab.script(),
+    describe = lab.experiment,
+    expect = Code.expect,
+    it = lab.it;
+
+function c(template, themeSettings) {
+    return new Paper({}, themeSettings).loadTemplatesSync({template: template}).render('template', {});
+}
+
+describe('resourceHints helper', function () {
+    it('should return the expected google resources', function (done) {
+        var themeSettings = {
+            'test1-font': 'Google_Open+Sans',
+            'test2-font': 'Google_Open+Sans_400italic',
+            'test3-font': 'Google_Open+Sans_700',
+            'test4-font': 'Google_Karla_700',
+            'test5-font': 'Google_Lora_400_sans',
+            'test6-font': 'Google_Volkron',
+            'test7-font': 'Google_Droid_400,700',
+            'test8-font': 'Google_Crimson+Text_400,700_sans',
+            'random-property': 'not a font'
+        };
+
+        var template = "{{resourceHints}}";
+
+        expect(c(template, themeSettings))
+            .to.be.equal('<link rel="dns-prefetch preconnect" href="//ajax.googleapis.com" crossorigin><link rel="dns-prefetch preconnect" href="//fonts.googleapis.com" crossorigin><link rel="dns-prefetch preconnect" href="//fonts.gstatic.com" crossorigin>');
+        done();
+    });
+});