✨ Helper Proxy & single express-hbs instance (#8225)

refs #8126, #8221, #8223

✨ New 'Proxy' for all helper requires
- this is not currently enforced, but could be, much like apps
- the proxy object is HUGE
- changed date to use SafeString, this should have been there anyway
- use the proxy for all helpers, including those in apps 😁

✨ 🎨 Single instance of hbs for theme + for errors
- we now have theme/engine instead of requiring express-hbs everywhere
- only error-handler still also requires express-hbs, this is so that we can render errors without extra crud
- TODO: remove the asset helper after #8126 IF it is not needed, or else remove the TODO

🎨 Cleanup visibility utils
🎨 Clean up the proxy a little bit
🚨 Unskip test as it now works!
🎨 Minor amends as per comments

core/server/apps/amp/lib/helpers/amp_components.js

@@ -7,7 +7,9 @@
 // Here's the list of all supported extended components: https://www.ampproject.org/docs/reference/extended.html
 // By default supported AMP HTML tags (no additional script tag necessary):
 // amp-img, amp-ad, amp-embed, amp-video and amp-pixel.
-var hbs             = require('express-hbs');
+// (less) dirty requires
+var proxy = require('../../../../helpers/proxy'),
+    SafeString = proxy.SafeString;
 
 function ampComponents() {
     var components = [],
@@ -29,7 +31,7 @@ function ampComponents() {
         components.push('<script async custom-element="amp-audio" src="https://cdn.ampproject.org/v0/amp-audio-0.1.js"></script>');
     }
 
-    return new hbs.handlebars.SafeString(components.join('\n'));
+    return new SafeString(components.join('\n'));
 }
 
 module.exports = ampComponents;

core/server/apps/amp/lib/helpers/amp_content.js

@@ -6,16 +6,19 @@
 //
 // Converts normal HTML into AMP HTML with Amperize module and uses a cache to return it from
 // there if available. The cacheId is a combination of `updated_at` and the `slug`.
-var hbs                  = require('express-hbs'),
-    Promise              = require('bluebird'),
-    moment               = require('moment'),
-    logging              = require('../../../../logging'),
-    i18n                 = require('../../../../i18n'),
-    errors               = require('../../../../errors'),
-    makeAbsoluteUrl      = require('../../../../utils/make-absolute-urls'),
-    utils                = require('../../../../utils'),
-    amperizeCache        = {},
-    allowedAMPTags       = [],
+var Promise = require('bluebird'),
+    moment = require('moment'),
+
+    // (less) dirty requires
+    proxy = require('../../../../helpers/proxy'),
+    SafeString = proxy.SafeString,
+    logging = proxy.logging,
+    i18n = proxy.i18n,
+    errors = proxy.errors,
+    makeAbsoluteUrl = require('../../../../utils/make-absolute-urls'),
+    utils = require('../../../../utils'),
+    amperizeCache = {},
+    allowedAMPTags = [],
     allowedAMPAttributes = {},
     amperize,
     cleanHTML,
@@ -190,7 +193,7 @@ function ampContent() {
             selfClosing: ['source', 'track']
         });
 
-        return new hbs.handlebars.SafeString(cleanHTML);
+        return new SafeString(cleanHTML);
     });
 }
 

core/server/apps/private-blogging/lib/helpers/input_password.js

@@ -6,12 +6,12 @@
 // We use the name input_password to match the helper for consistency:
 // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
 
-// Dirty requires
-var hbs = require('express-hbs'),
-    utils = require('../../../../helpers/utils'),
-    input_password;
+// (less) dirty requires
+var proxy = require('../../../../helpers/proxy'),
+    SafeString = proxy.SafeString,
+    templates = proxy.templates;
 
-input_password = function (options) {
+module.exports = function input_password(options) {
     options = options || {};
     options.hash = options.hash || {};
 
@@ -23,14 +23,12 @@ input_password = function (options) {
         extras += ' placeholder="' + options.hash.placeholder + '"';
     }
 
-    output = utils.inputTemplate({
+    output = templates.input({
         type: 'password',
         name: 'password',
         className: className,
         extras: extras
     });
 
-    return new hbs.handlebars.SafeString(output);
+    return new SafeString(output);
 };
-
-module.exports = input_password;

core/server/apps/proxy.js

@@ -1,6 +1,6 @@
 var _           = require('lodash'),
     api         = require('../api'),
-    helpers     = require('../helpers'),
+    helpers     = require('../helpers/register'),
     filters     = require('../filters'),
     i18n        = require('../i18n'),
     generateProxyFunctions;

core/server/apps/subscribers/lib/helpers/input_email.js

@@ -6,12 +6,12 @@
 // We use the name input_email to match the helper for consistency:
 // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
 
-// Dirty requires
-var hbs = require('express-hbs'),
-    utils = require('../../../../helpers/utils'),
-    input_email;
+// (less) dirty requires
+var proxy = require('../../../../helpers/proxy'),
+    SafeString = proxy.SafeString,
+    templates = proxy.templates;
 
-input_email = function (options) {
+module.exports = function input_email(options) {
     options = options || {};
     options.hash = options.hash || {};
 
@@ -31,14 +31,13 @@ input_email = function (options) {
         extras += ' value="' + options.hash.value + '"';
     }
 
-    output = utils.inputTemplate({
+    output = templates.input({
         type: 'email',
         name: 'email',
         className: className,
         extras: extras
     });
 
-    return new hbs.handlebars.SafeString(output);
+    return new SafeString(output);
 };
 
-module.exports = input_email;

core/server/apps/subscribers/lib/helpers/subscribe_form.js

@@ -5,20 +5,19 @@
 // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
 var _ = require('lodash'),
 
-    // Dirty requires
-    hbs = require('express-hbs'),
-    config = require('../../../../config'),
-    template = require('../../../../helpers/template'),
-    utils = require('../../../../helpers/utils'),
-    globalUtils = require('../../../../utils'),
+    // (Less) dirty requires
+    proxy = require('../../../../helpers/proxy'),
+    templates = proxy.templates,
+    config = proxy.config,
+    url = proxy.url,
+    SafeString = proxy.SafeString,
 
     params = ['error', 'success', 'email'],
 
-    subscribe_form,
     subscribeScript;
 
 function makeHidden(name, extras) {
-    return utils.inputTemplate({
+    return templates.input({
         type: 'hidden',
         name: name,
         className: name,
@@ -39,19 +38,17 @@ subscribeScript =
     '})(window,document,\'querySelector\',\'value\');' +
     '</script>';
 
-subscribe_form = function (options) {
+module.exports = function subscribe_form(options) {
     var root = options.data.root,
         data = _.merge({}, options.hash, _.pick(root, params), {
-            action: globalUtils.url.urlJoin('/', globalUtils.url.getSubdir(), config.get('routeKeywords').subscribe, '/'),
-            script: new hbs.handlebars.SafeString(subscribeScript),
-            hidden: new hbs.handlebars.SafeString(
+            action: url.urlJoin('/', url.getSubdir(), config.get('routeKeywords').subscribe, '/'),
+            script: new SafeString(subscribeScript),
+            hidden: new SafeString(
                 makeHidden('confirm') +
                 makeHidden('location', root.subscribed_url ? 'value=' + root.subscribed_url : '') +
                 makeHidden('referrer', root.subscribed_referrer ? 'value=' + root.subscribed_referrer : '')
             )
         });
 
-    return template.execute('subscribe_form', data, options);
+    return templates.execute('subscribe_form', data, options);
 };
-
-module.exports = subscribe_form;

core/server/data/meta/keywords.js

@@ -1,4 +1,4 @@
-var visibilityFilter = require('../../utils/visibility-filter');
+var visibilityFilter = require('../../utils/visibility').filter;
 
 function getKeywords(data) {
     if (data.post && data.post.tags && data.post.tags.length > 0) {

core/server/data/meta/schema.js

@@ -1,7 +1,6 @@
 var config = require('../../config'),
-    hbs = require('express-hbs'),
+    escapeExpression = require('../../themes/engine').escapeExpression,
     socialUrls = require('../../utils/social-urls'),
-    escapeExpression = hbs.handlebars.Utils.escapeExpression,
     _ = require('lodash');
 
 function schemaImageObject(metaDataVal) {

core/server/helpers/asset.js

@@ -2,12 +2,12 @@
 // Usage: `{{asset "css/screen.css"}}`, `{{asset "css/screen.css" ghost="true"}}`
 //
 // Returns the path to the specified asset. The ghost flag outputs the asset path for the Ghost admin
+var proxy = require('./proxy'),
+    config = proxy.config,
+    getAssetUrl = proxy.metaData.getAssetUrl,
+    SafeString = proxy.SafeString;
 
-var config = require('../config'),
-    getAssetUrl = require('../data/meta/asset_url'),
-    hbs = require('express-hbs');
-
-function asset(path, options) {
+module.exports = function asset(path, options) {
     var isAdmin,
         minify;
 
@@ -20,9 +20,7 @@ function asset(path, options) {
         minify = false;
     }
 
-    return new hbs.handlebars.SafeString(
+    return new SafeString(
         getAssetUrl(path, isAdmin, minify)
     );
-}
-
-module.exports = asset;
+};

core/server/helpers/author.js

@@ -10,15 +10,16 @@
 // Block helper: `{{#author}}{{/author}}`
 // This is the default handlebars behaviour of dropping into the author object scope
 
-var hbs             = require('express-hbs'),
-    _               = require('lodash'),
-    utils          = require('../utils'),
-    localUtils     = require('./utils'),
-    author;
+var proxy = require('./proxy'),
+    _ = require('lodash'),
+    SafeString = proxy.SafeString,
+    handlebars = proxy.hbs.handlebars,
+    templates = proxy.templates,
+    url = proxy.url;
 
-author = function (options) {
+module.exports = function author(options) {
     if (options.fn) {
-        return hbs.handlebars.helpers.with.call(this, this.author, options);
+        return handlebars.helpers.with.call(this, this.author, options);
     }
 
     var autolink = _.isString(options.hash.autolink) && options.hash.autolink === 'false' ? false : true,
@@ -26,8 +27,8 @@ author = function (options) {
 
     if (this.author && this.author.name) {
         if (autolink) {
-            output = localUtils.linkTemplate({
-                url: utils.url.urlFor('author', {author: this.author}),
+            output = templates.link({
+                url: url.urlFor('author', {author: this.author}),
                 text: _.escape(this.author.name)
             });
         } else {
@@ -35,7 +36,5 @@ author = function (options) {
         }
     }
 
-    return new hbs.handlebars.SafeString(output);
+    return new SafeString(output);
 };
-
-module.exports = author;

core/server/helpers/body_class.js

@@ -6,11 +6,11 @@
 // We use the name body_class to match the helper for consistency:
 // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
 
-var hbs             = require('express-hbs'),
-    _               = require('lodash'),
-    body_class;
+var proxy = require('./proxy'),
+    _ = require('lodash'),
+    SafeString = proxy.SafeString;
 
-body_class = function (options) {
+module.exports = function body_class(options) {
     var classes = [],
         context = options.data.root.context,
         post = this.post,
@@ -43,7 +43,6 @@ body_class = function (options) {
     }
 
     classes = _.reduce(classes, function (memo, item) { return memo + ' ' + item; }, '');
-    return new hbs.handlebars.SafeString(classes.trim());
+    return new SafeString(classes.trim());
 };
 
-module.exports = body_class;

core/server/helpers/content.js

@@ -6,12 +6,12 @@
 //
 // Enables tag-safe truncation of content by characters or words.
 
-var hbs             = require('express-hbs'),
-    _               = require('lodash'),
-    downsize        = require('downsize'),
-    content;
+var proxy = require('./proxy'),
+    _ = require('lodash'),
+    downsize = require('downsize'),
+    SafeString = proxy.SafeString;
 
-content = function (options) {
+module.exports = function content(options) {
     var truncateOptions = (options || {}).hash || {};
     truncateOptions = _.pick(truncateOptions, ['words', 'characters']);
     _.keys(truncateOptions).map(function (key) {
@@ -19,12 +19,10 @@ content = function (options) {
     });
 
     if (truncateOptions.hasOwnProperty('words') || truncateOptions.hasOwnProperty('characters')) {
-        return new hbs.handlebars.SafeString(
+        return new SafeString(
             downsize(this.html, truncateOptions)
         );
     }
 
-    return new hbs.handlebars.SafeString(this.html);
+    return new SafeString(this.html);
 };
-
-module.exports = content;

core/server/helpers/date.js

@@ -3,11 +3,13 @@
 //
 // Formats a date using moment-timezone.js. Formats published_at by default but will also take a date as a parameter
 
-var moment = require('moment-timezone'),
-    date,
-    timezone;
+var proxy = require('./proxy'),
+    moment = require('moment-timezone'),
+    SafeString = proxy.SafeString;
+
+module.exports = function (date, options) {
+    var timezone, format, timeago, timeNow;
 
-date = function (date, options) {
     if (!options && date.hasOwnProperty('hash')) {
         options = date;
         date = undefined;
@@ -23,17 +25,15 @@ date = function (date, options) {
     // ensure that context is undefined, not null, as that can cause errors
     date = date === null ? undefined : date;
 
-    var f = options.hash.format || 'MMM DD, YYYY',
-        timeago = options.hash.timeago,
-        timeNow = moment().tz(timezone);
+    format = options.hash.format || 'MMM DD, YYYY';
+    timeago = options.hash.timeago;
+    timeNow = moment().tz(timezone);
 
     if (timeago) {
-        date = timezone ?  moment(date).tz(timezone).from(timeNow) : moment(date).fromNow();
+        date = timezone ? moment(date).tz(timezone).from(timeNow) : moment(date).fromNow();
     } else {
-        date = timezone ? moment(date).tz(timezone).format(f) : moment(date).format(f);
+        date = timezone ? moment(date).tz(timezone).format(format) : moment(date).format(format);
     }
 
-    return date;
+    return new SafeString(date);
 };
-
-module.exports = date;

core/server/helpers/encode.js

@@ -4,12 +4,10 @@
 //
 // Returns URI encoded string
 
-var hbs = require('express-hbs'),
-    encode;
+var proxy = require('./proxy'),
+    SafeString = proxy.SafeString;
 
-encode = function (string, options) {
+module.exports = function encode(string, options) {
     var uri = string || options;
-    return new hbs.handlebars.SafeString(encodeURIComponent(uri));
+    return new SafeString(encodeURIComponent(uri));
 };
-
-module.exports = encode;

core/server/helpers/excerpt.js

@@ -5,11 +5,12 @@
 //
 // Defaults to words="50"
 
-var hbs = require('express-hbs'),
-    _   = require('lodash'),
-    getMetaDataExcerpt = require('../data/meta/excerpt');
+var proxy = require('./proxy'),
+    _ = require('lodash'),
+    SafeString = proxy.SafeString,
+    getMetaDataExcerpt = proxy.metaData.getMetaDataExcerpt;
 
-function excerpt(options) {
+module.exports = function excerpt(options) {
     var truncateOptions = (options || {}).hash || {};
 
     truncateOptions = _.pick(truncateOptions, ['words', 'characters']);
@@ -17,9 +18,7 @@ function excerpt(options) {
         truncateOptions[key] = parseInt(truncateOptions[key], 10);
     });
 
-    return new hbs.handlebars.SafeString(
+    return new SafeString(
         getMetaDataExcerpt(String(this.html), truncateOptions)
     );
-}
-
-module.exports = excerpt;
+};

core/server/helpers/facebook_url.js

@@ -6,11 +6,11 @@
 // We use the name facebook_url to match the helper for consistency:
 // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
 
-var socialUrls = require('../utils/social-urls'),
-    findKey    = require('./utils').findKey,
-    facebook_url;
+var proxy = require('./proxy'),
+    socialUrls = proxy.socialUrls,
+    findKey = proxy.utils.findKey;
 
-facebook_url = function (username, options) {
+module.exports = function facebook_url(username, options) {
     if (!options) {
         options = username;
         username = findKey('facebook', this, options.data.blog);
@@ -22,5 +22,3 @@ facebook_url = function (username, options) {
 
     return null;
 };
-
-module.exports = facebook_url;

core/server/helpers/foreach.js

@@ -2,23 +2,21 @@
 // Usage: `{{#foreach data}}{{/foreach}}`
 //
 // Block helper designed for looping through posts
-var hbs             = require('express-hbs'),
-    _               = require('lodash'),
-    logging         = require('../logging'),
-    i18n            = require('../i18n'),
-    visibilityFilter = require('../utils/visibility-filter'),
-    utils           = require('./utils'),
-
-    hbsUtils        = hbs.handlebars.Utils,
-    foreach;
+var proxy = require('./proxy'),
+    _ = require('lodash'),
+    logging = proxy.logging,
+    i18n = proxy.i18n,
+    visibilityUtils = proxy.visibility,
+    hbsUtils = proxy.hbs.Utils,
+    createFrame = proxy.hbs.handlebars.createFrame;
 
 function filterItemsByVisibility(items, options) {
-    var visibility = utils.parseVisibility(options);
+    var visibility = visibilityUtils.parser(options);
 
-    return visibilityFilter(items, visibility, !!options.hash.visibility);
+    return visibilityUtils.filter(items, visibility, !!options.hash.visibility);
 }
 
-foreach = function (items, options) {
+module.exports = function foreach(items, options) {
     if (!options) {
         logging.warn(i18n.t('warnings.helpers.foreach.iteratorNeeded'));
     }
@@ -53,7 +51,7 @@ foreach = function (items, options) {
     }
 
     if (options.data) {
-        data = hbs.handlebars.createFrame(options.data);
+        data = createFrame(options.data);
     }
 
     function execIteration(field, index, last) {
@@ -73,9 +71,9 @@ foreach = function (items, options) {
         }
 
         output = output + fn(items[field], {
-            data: data,
-            blockParams: hbsUtils.blockParams([items[field], field], [contextPath + field, null])
-        });
+                data: data,
+                blockParams: hbsUtils.blockParams([items[field], field], [contextPath + field, null])
+            });
     }
 
     function iterateCollection(context) {
@@ -109,5 +107,3 @@ foreach = function (items, options) {
 
     return output;
 };
-
-module.exports = foreach;

core/server/helpers/get.js

@@ -1,15 +1,17 @@
 // # Get Helper
 // Usage: `{{#get "posts" limit="5"}}`, `{{#get "tags" limit="all"}}`
 // Fetches data from the API
-var _ = require('lodash'),
-    hbs = require('express-hbs'),
+var proxy = require('./proxy'),
+    _ = require('lodash'),
     Promise = require('bluebird'),
     jsonpath = require('jsonpath'),
 
-    logging = require('../logging'),
-    i18n = require('../i18n'),
-    api = require('../api'),
-    labs = require('../utils/labs'),
+    logging = proxy.logging,
+    i18n = proxy.i18n,
+    createFrame = proxy.hbs.handlebars.createFrame,
+
+    api = proxy.api,
+    labs = proxy.labs,
     resources,
     pathAliases,
     get;
@@ -96,7 +98,7 @@ get = function get(resource, options) {
     options.data = options.data || {};
 
     var self = this,
-        data = hbs.handlebars.createFrame(options.data),
+        data = createFrame(options.data),
         apiOptions = options.hash,
         apiMethod;
 

core/server/helpers/ghost_foot.js

@@ -5,14 +5,13 @@
 //
 // We use the name ghost_foot to match the helper for consistency:
 // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
-var hbs = require('express-hbs'),
-    SafeString = hbs.handlebars.SafeString,
+var proxy = require('./proxy'),
     _ = require('lodash'),
-    filters = require('../filters'),
-    settingsCache = require('../settings/cache'),
-    ghost_foot;
+    SafeString = proxy.SafeString,
+    filters = proxy.filters,
+    settingsCache = proxy.settingsCache;
 
-ghost_foot = function ghost_foot() {
+module.exports = function ghost_foot() {
     var foot = [],
         codeInjection = settingsCache.get('ghost_foot');
 
@@ -26,5 +25,3 @@ ghost_foot = function ghost_foot() {
             return new SafeString(foot.join(' ').trim());
         });
 };
-
-module.exports = ghost_foot;

core/server/helpers/ghost_head.js

@@ -6,19 +6,19 @@
 // We use the name ghost_head to match the helper for consistency:
 // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
 
-var getMetaData = require('../data/meta'),
-    hbs = require('express-hbs'),
-    escapeExpression = hbs.handlebars.Utils.escapeExpression,
-    SafeString = hbs.handlebars.SafeString,
+var proxy = require('./proxy'),
     _ = require('lodash'),
-    filters = require('../filters'),
-    assetHelper = require('./asset'),
-    config = require('../config'),
     Promise = require('bluebird'),
-    labs = require('../utils/labs'),
-    utils = require('../utils'),
-    api = require('../api'),
-    settingsCache = require('../settings/cache');
+
+    getMetaData = proxy.metaData.get,
+    escapeExpression = proxy.escapeExpression,
+    SafeString = proxy.SafeString,
+    filters = proxy.filters,
+    labs = proxy.labs,
+    api = proxy.api,
+    settingsCache = proxy.settingsCache,
+    config = proxy.config,
+    url = proxy.url;
 
 function getClient() {
     if (labs.isSet('publicAPI') === true) {
@@ -66,6 +66,10 @@ function finaliseStructuredData(metaData) {
 }
 
 function getAjaxHelper(clientId, clientSecret) {
+    // @TODO: swap this for a direct utility, rather than using the helper? see #8221
+    // Note: this is here because the asset helper isn't registered when this file is first loaded
+    var assetHelper = proxy.hbs.handlebars.helpers.asset;
+
     return '<script type="text/javascript" src="' +
         assetHelper('shared/ghost-url.js', {hash: {minifyInProduction: true}}) + '"></script>\n' +
         '<script type="text/javascript">\n' +
@@ -76,7 +80,7 @@ function getAjaxHelper(clientId, clientSecret) {
         '</script>';
 }
 
-function ghost_head(options) {
+module.exports = function ghost_head(options) {
     // if server error page do nothing
     if (this.statusCode >= 500) {
         return;
@@ -97,7 +101,7 @@ function ghost_head(options) {
         blogIcon = settingsCache.get('icon'),
         // CASE: blog icon is not set in config, we serve the default
         iconType = !blogIcon ? 'x-icon' : blogIcon.match(/\/favicon\.ico$/i) ? 'x-icon' : 'png',
-        favicon = !blogIcon ? '/favicon.ico' : utils.url.urlFor('image', {image: blogIcon});
+        favicon = !blogIcon ? '/favicon.ico' : url.urlFor('image', {image: blogIcon});
 
     return Promise.props(fetch).then(function (response) {
         client = response.client;
@@ -162,6 +166,4 @@ function ghost_head(options) {
     }).then(function (head) {
         return new SafeString(head.join('\n    ').trim());
     });
-}
-
-module.exports = ghost_head;
+};

core/server/helpers/has.js

@@ -3,12 +3,12 @@
 //
 // Checks if a post has a particular property
 
-var _               = require('lodash'),
-    logging         = require('../logging'),
-    i18n            = require('../i18n'),
-    has;
+var proxy = require('./proxy'),
+    _ = require('lodash'),
+    logging = proxy.logging,
+    i18n = proxy.i18n;
 
-has = function (options) {
+module.exports = function has(options) {
     options = options || {};
     options.hash = options.hash || {};
 
@@ -33,7 +33,7 @@ has = function (options) {
     }
 
     function evaluateAuthorList(expr, author) {
-        var authorList =  expr.split(',').map(function (v) {
+        var authorList = expr.split(',').map(function (v) {
             return v.trim().toLocaleLowerCase();
         });
 
@@ -53,5 +53,3 @@ has = function (options) {
     }
     return options.inverse(this);
 };
-
-module.exports = has;

core/server/helpers/image.js

@@ -4,15 +4,13 @@
 // Returns the URL for the current object scope i.e. If inside a post scope will return image permalink
 // `absolute` flag outputs absolute URL, else URL is relative.
 
-var utils  = require('../utils'),
-    image;
+var proxy = require('./proxy'),
+    url = proxy.url;
 
-image = function (options) {
+module.exports = function image(options) {
     var absolute = options && options.hash.absolute;
 
     if (this.image) {
-        return utils.url.urlFor('image', {image: this.image}, absolute);
+        return url.urlFor('image', {image: this.image}, absolute);
     }
 };
-
-module.exports = image;

core/server/helpers/index.js

@@ -1,14 +1,8 @@
-var hbs = require('express-hbs'),
-    Promise = require('bluebird'),
-    errors = require('../errors'),
-    config = require('../config'),
-    coreHelpers = {},
-    registerHelpers;
-
-// @TODO think about a config option for this e.g. theme.devmode?
-if (config.get('env') !== 'production') {
-    hbs.handlebars.logger.level = 0;
-}
+var coreHelpers = {},
+    register = require('./register'),
+    registerThemeHelper = register.registerThemeHelper,
+    registerAsyncThemeHelper = register.registerAsyncThemeHelper,
+    registerAllCoreHelpers;
 
 coreHelpers.asset = require('./asset');
 coreHelpers.author = require('./author');
@@ -39,38 +33,7 @@ coreHelpers.title = require('./title');
 coreHelpers.twitter_url = require('./twitter_url');
 coreHelpers.url = require('./url');
 
-// Register an async handlebars helper for a given handlebars instance
-function registerAsyncHelper(hbs, name, fn) {
-    hbs.registerAsyncHelper(name, function (context, options, cb) {
-        // Handle the case where we only get context and cb
-        if (!cb) {
-            cb = options;
-            options = undefined;
-        }
-
-        // Wrap the function passed in with a when.resolve so it can return either a promise or a value
-        Promise.resolve(fn.call(this, context, options)).then(function (result) {
-            cb(result);
-        }).catch(function (err) {
-            throw new errors.IncorrectUsageError({
-                err: err,
-                context: 'registerAsyncThemeHelper: ' + name
-            });
-        });
-    });
-}
-
-// Register a handlebars helper for themes
-function registerThemeHelper(name, fn) {
-    hbs.registerHelper(name, fn);
-}
-
-// Register an async handlebars helper for themes
-function registerAsyncThemeHelper(name, fn) {
-    registerAsyncHelper(hbs, name, fn);
-}
-
-registerHelpers = function () {
+registerAllCoreHelpers = function registerAllCoreHelpers() {
     // Register theme helpers
     registerThemeHelper('asset', coreHelpers.asset);
     registerThemeHelper('author', coreHelpers.author);
@@ -105,6 +68,4 @@ registerHelpers = function () {
 };
 
 module.exports = coreHelpers;
-module.exports.loadCoreHelpers = registerHelpers;
-module.exports.registerThemeHelper = registerThemeHelper;
-module.exports.registerAsyncThemeHelper = registerAsyncThemeHelper;
+module.exports.loadCoreHelpers = registerAllCoreHelpers;

core/server/helpers/is.js

@@ -1,12 +1,12 @@
 // # Is Helper
 // Usage: `{{#is "paged"}}`, `{{#is "index, paged"}}`
 // Checks whether we're in a given context.
-var _               = require('lodash'),
-    logging         = require('../logging'),
-    i18n            = require('../i18n'),
-    is;
+var proxy = require('./proxy'),
+    _ = require('lodash'),
+    logging = proxy.logging,
+    i18n = proxy.i18n;
 
-is = function (context, options) {
+module.exports = function is(context, options) {
     options = options || {};
 
     var currentContext = options.data.root.context;
@@ -30,4 +30,3 @@ is = function (context, options) {
     return options.inverse(this);
 };
 
-module.exports = is;

core/server/helpers/meta_description.js

@@ -6,7 +6,8 @@
 // We use the name meta_description to match the helper for consistency:
 // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
 
-var getMetaDataDescription = require('../data/meta/description');
+var proxy = require('./proxy'),
+    getMetaDataDescription = proxy.metaData.getMetaDataDescription;
 
 function meta_description(options) {
     options = options || {};

core/server/helpers/meta_title.js

@@ -6,7 +6,8 @@
 // We use the name meta_title to match the helper for consistency:
 // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
 
-var getMetaDataTitle = require('../data/meta/title');
+var proxy = require('./proxy'),
+    getMetaDataTitle = proxy.metaData.getMetaDataTitle;
 
 function meta_title(options) {
     return getMetaDataTitle(this, options.data.root);

core/server/helpers/navigation.js

@@ -2,15 +2,14 @@
 // `{{navigation}}`
 // Outputs navigation menu of static urls
 
-var _ = require('lodash'),
-    hbs = require('express-hbs'),
-    i18n = require('../i18n'),
-    errors = require('../errors'),
-    template = require('./template'),
-    navigation;
+var proxy = require('./proxy'),
+    _ = require('lodash'),
+    SafeString = proxy.SafeString,
+    i18n = proxy.i18n,
+    errors = proxy.errors,
+    templates = proxy.templates;
 
-navigation = function (options) {
-    /*jshint unused:false*/
+module.exports = function navigation(options) {
     var navigationData = options.data.blog.navigation,
         currentUrl = options.data.root.relativeUrl,
         self = this,
@@ -58,7 +57,7 @@ navigation = function (options) {
 
     // {{navigation}} should no-op if no data passed in
     if (navigationData.length === 0) {
-        return new hbs.SafeString('');
+        return new SafeString('');
     }
 
     output = navigationData.map(function (e) {
@@ -73,7 +72,6 @@ navigation = function (options) {
 
     data = _.merge({}, {navigation: output});
 
-    return template.execute('navigation', data, options);
+    return templates.execute('navigation', data, options);
 };
 
-module.exports = navigation;

core/server/helpers/page_url.js

@@ -8,15 +8,13 @@
 //
 // We use the name page_url to match the helper for consistency:
 // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
-var getPaginatedUrl = require('../data/meta/paginated_url'),
-    page_url;
+var proxy = require('./proxy'),
+    getPaginatedUrl = proxy.metaData.getPaginatedUrl;
 
-page_url = function (page, options) {
+module.exports = function page_url(page, options) {
     if (!options) {
         options = page;
         page = 1;
     }
     return getPaginatedUrl(page, options.data.root);
 };
-
-module.exports = page_url;

core/server/helpers/pagination.js

@@ -2,10 +2,11 @@
 // `{{pagination}}`
 // Outputs previous and next buttons, along with info about the current page
 
-var _               = require('lodash'),
-    errors          = require('../errors'),
-    i18n            = require('../i18n'),
-    template        = require('./template'),
+var proxy = require('./proxy'),
+    _ = require('lodash'),
+    errors = proxy.errors,
+    i18n = proxy.i18n,
+    templates = proxy.templates,
     pagination;
 
 pagination = function (options) {
@@ -37,7 +38,7 @@ pagination = function (options) {
 
     var data = _.merge({}, this.pagination);
 
-    return template.execute('pagination', data, options);
+    return templates.execute('pagination', data, options);
 };
 
 module.exports = pagination;

core/server/helpers/plural.js

@@ -8,13 +8,13 @@
 // The 3rd argument is the string that will be output if the variable's value is 1
 // The 4th argument is the string that will be output if the variable's value is 2+
 
-var hbs             = require('express-hbs'),
-    errors          = require('../errors'),
-    i18n            = require('../i18n'),
-    _               = require('lodash'),
-    plural;
+var proxy = require('./proxy'),
+    _ = require('lodash'),
+    errors = proxy.errors,
+    i18n = proxy.i18n,
+    SafeString = proxy.SafeString;
 
-plural = function (number, options) {
+module.exports = function plural(number, options) {
     if (_.isUndefined(options.hash) || _.isUndefined(options.hash.empty) ||
         _.isUndefined(options.hash.singular) || _.isUndefined(options.hash.plural)) {
         throw new errors.IncorrectUsageError({
@@ -23,12 +23,11 @@ plural = function (number, options) {
     }
 
     if (number === 0) {
-        return new hbs.handlebars.SafeString(options.hash.empty.replace('%', number));
+        return new SafeString(options.hash.empty.replace('%', number));
     } else if (number === 1) {
-        return new hbs.handlebars.SafeString(options.hash.singular.replace('%', number));
+        return new SafeString(options.hash.singular.replace('%', number));
     } else if (number >= 2) {
-        return new hbs.handlebars.SafeString(options.hash.plural.replace('%', number));
+        return new SafeString(options.hash.plural.replace('%', number));
     }
 };
 
-module.exports = plural;

core/server/helpers/post_class.js

@@ -6,19 +6,20 @@
 // We use the name body_class to match the helper for consistency:
 // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
 
-var hbs             = require('express-hbs'),
-    _               = require('lodash'),
-    post_class;
+var proxy = require('./proxy'),
+    _ = require('lodash'),
+    SafeString = proxy.SafeString;
 
-post_class = function (options) {
-    /*jshint unused:false*/
+module.exports = function post_class() {
     var classes = ['post'],
         tags = this.post && this.post.tags ? this.post.tags : this.tags || [],
         featured = this.post && this.post.featured ? this.post.featured : this.featured || false,
         page = this.post && this.post.page ? this.post.page : this.page || false;
 
     if (tags) {
-        classes = classes.concat(tags.map(function (tag) { return 'tag-' + tag.slug; }));
+        classes = classes.concat(tags.map(function (tag) {
+            return 'tag-' + tag.slug;
+        }));
     }
 
     if (featured) {
@@ -29,8 +30,8 @@ post_class = function (options) {
         classes.push('page');
     }
 
-    classes = _.reduce(classes, function (memo, item) { return memo + ' ' + item; }, '');
-    return new hbs.handlebars.SafeString(classes.trim());
+    classes = _.reduce(classes, function (memo, item) {
+        return memo + ' ' + item;
+    }, '');
+    return new SafeString(classes.trim());
 };
-
-module.exports = post_class;

core/server/helpers/prev_next.js

@@ -3,12 +3,15 @@
 // `{{#prev_post}}<a href ="{{url}}>previous post</a>{{/prev_post}}'
 // `{{#next_post}}<a href ="{{url absolute="true">next post</a>{{/next_post}}'
 
-var api             = require('../api'),
-    schema          = require('../data/schema').checks,
-    Promise         = require('bluebird'),
-    fetch, prevNext;
+var proxy = require('./proxy'),
+    Promise = require('bluebird'),
 
-fetch = function (apiOptions, options) {
+    api = proxy.api,
+    isPost = proxy.checks.isPost,
+
+    fetch;
+
+fetch = function fetch(apiOptions, options) {
     return api.posts.read(apiOptions).then(function (result) {
         var related = result.posts[0];
 
@@ -25,19 +28,17 @@ fetch = function (apiOptions, options) {
 // If prevNext method is called without valid post data then we must return a promise, if there is valid post data
 // then the promise is handled in the api call.
 
-prevNext = function (options) {
+module.exports = function prevNext(options) {
     options = options || {};
 
     var apiOptions = {
         include: options.name === 'prev_post' ? 'previous,previous.author,previous.tags' : 'next,next.author,next.tags'
     };
 
-    if (schema.isPost(this) && this.status === 'published') {
+    if (isPost(this) && this.status === 'published') {
         apiOptions.slug = this.slug;
         return fetch(apiOptions, options);
     } else {
         return Promise.resolve(options.inverse(this));
     }
 };
-
-module.exports = prevNext;

core/server/helpers/proxy.js

@@ -0,0 +1,81 @@
+// This file defines everything that helpers "require"
+// With the exception of modules like lodash, Bluebird
+// We can later refactor to enforce this something like we do in apps
+var hbs = require('../themes/engine'),
+    _ = require('lodash'),
+    settingsCache = require('../settings/cache'),
+    config = require('../config');
+
+// Direct requires:
+// - lodash
+// - bluebird
+// - downsize
+// - moment-timezone
+// - jsonpath
+
+module.exports = {
+    hbs: hbs,
+    SafeString: hbs.SafeString,
+    escapeExpression: hbs.escapeExpression,
+
+    // TODO: Expose less of the API to make this safe
+    api: require('../api'),
+    // TODO: Only expose "get"
+    settingsCache: settingsCache,
+
+    // These 3 are kind of core and required all the time
+    errors: require('../errors'),
+    i18n: require('../i18n'),
+    logging: require('../logging'),
+
+    // This is used to detect if "isPost" is true in prevNext.
+    checks: require('../data/schema').checks,
+
+    // Config!
+    // Keys used:
+    // minifyAssets in asset helper
+    // isPrivacyDisabled & referrerPolicy used in ghost_head
+    // Subscribe app uses routeKeywords
+    config: {
+        get: config.get.bind(config),
+        isPrivacyDisabled: config.isPrivacyDisabled.bind(config)
+    },
+
+    // Labs utils for enabling/disabling helpers
+    labs: require('../utils/labs'),
+
+    // System for apps to hook into one day maybe
+    filters: require('../filters'),
+
+    // Things required from data/meta
+    metaData: {
+        get: require('../data/meta'), // ghost_head
+        getAssetUrl: require('../data/meta/asset_url'), // asset
+        getMetaDataExcerpt: require('../data/meta/excerpt'), // excerpt
+        getMetaDataDescription: require('../data/meta/description'), // meta_desc
+        getMetaDataTitle: require('../data/meta/title'), // meta_title
+        getPaginatedUrl: require('../data/meta/paginated_url'), // page_url
+        getMetaDataUrl: require('../data/meta/url') // url
+    },
+
+    // The local template thing, should this be merged with the channels one?
+    templates: require('./template'),
+
+    // Various utils, needs cleaning up / simplifying
+    socialUrls: require('../utils/social-urls'),
+    url: require('../utils').url,
+    utils: {
+        findKey: function findKey(key /* ...objects... */) {
+            var objects = Array.prototype.slice.call(arguments, 1);
+
+            return _.reduceRight(objects, function (result, object) {
+                if (object && _.has(object, key) && !_.isEmpty(object[key])) {
+                    result = object[key];
+                }
+
+                return result;
+            }, null);
+        }
+    },
+    visibility: require('../utils/visibility')
+};

core/server/helpers/register.js

@@ -0,0 +1,34 @@
+var hbs = require('../themes/engine'),
+    Promise = require('bluebird'),
+    errors = require('../errors');
+
+// Register an async handlebars helper for a given handlebars instance
+function asyncHelperWrapper(hbs, name, fn) {
+    hbs.registerAsyncHelper(name, function returnAsync(context, options, cb) {
+        // Handle the case where we only get context and cb
+        if (!cb) {
+            cb = options;
+            options = undefined;
+        }
+
+        // Wrap the function passed in with a when.resolve so it can return either a promise or a value
+        Promise.resolve(fn.call(this, context, options)).then(function (result) {
+            cb(result);
+        }).catch(function (err) {
+            throw new errors.IncorrectUsageError({
+                err: err,
+                context: 'registerAsyncThemeHelper: ' + name
+            });
+        });
+    });
+}
+
+// Register a handlebars helper for themes
+module.exports.registerThemeHelper = function registerThemeHelper(name, fn) {
+    hbs.registerHelper(name, fn);
+};
+
+// Register an async handlebars helper for themes
+module.exports.registerAsyncThemeHelper = function registerAsyncThemeHelper(name, fn) {
+    asyncHelperWrapper(hbs, name, fn);
+};

core/server/helpers/tags.js

@@ -6,14 +6,15 @@
 //
 // Note that the standard {{#each tags}} implementation is unaffected by this helper
 
-var hbs             = require('express-hbs'),
-    _               = require('lodash'),
-    utils           = require('../utils'),
-    localUtils      = require('./utils'),
-    visibilityFilter = require('../utils/visibility-filter'),
-    tags;
+var proxy = require('./proxy'),
+    _ = require('lodash'),
 
-tags = function (options) {
+    SafeString = proxy.SafeString,
+    templates = proxy.templates,
+    url = proxy.url,
+    visibilityUtils = proxy.visibility;
+
+module.exports = function tags(options) {
     options = options || {};
     options.hash = options.hash || {};
 
@@ -24,18 +25,18 @@ tags = function (options) {
         limit      = options.hash.limit ? parseInt(options.hash.limit, 10) : undefined,
         from       = options.hash.from ? parseInt(options.hash.from, 10) : 1,
         to         = options.hash.to ? parseInt(options.hash.to, 10) : undefined,
-        visibility = localUtils.parseVisibility(options),
+        visibility = visibilityUtils.parser(options),
         output     = '';
 
     function createTagList(tags) {
         function processTag(tag) {
-            return autolink ? localUtils.linkTemplate({
-                url: utils.url.urlFor('tag', {tag: tag}),
+            return autolink ? templates.link({
+                url: url.urlFor('tag', {tag: tag}),
                 text: _.escape(tag.name)
             }) : _.escape(tag.name);
         }
 
-        return visibilityFilter(tags, visibility, !!options.hash.visibility, processTag);
+        return visibilityUtils.filter(tags, visibility, !!options.hash.visibility, processTag);
     }
 
     if (this.tags && this.tags.length) {
@@ -49,7 +50,5 @@ tags = function (options) {
         output = prefix + output + suffix;
     }
 
-    return new hbs.handlebars.SafeString(output);
+    return new SafeString(output);
 };
-
-module.exports = tags;

core/server/helpers/template.js

@@ -1,13 +1,15 @@
-var templates     = {},
-    hbs           = require('express-hbs'),
-    errors        = require('../errors'),
-    i18n          = require('../i18n');
+var templates = {},
+
+    _ = require('lodash'),
+    hbs = require('../themes/engine'),
+    errors = require('../errors'),
+    i18n = require('../i18n');
 
 // ## Template utils
 
 // Execute a template helper
 // All template helpers are register as partial view.
-templates.execute = function (name, context, options) {
+templates.execute = function execute(name, context, options) {
     var partial = hbs.handlebars.partials[name];
 
     if (partial === undefined) {
@@ -21,7 +23,12 @@ templates.execute = function (name, context, options) {
         hbs.registerPartial(partial);
     }
 
-    return new hbs.handlebars.SafeString(partial(context, options));
+    return new hbs.SafeString(partial(context, options));
 };
 
+templates.asset = _.template('<%= source %>?v=<%= version %>');
+templates.link = _.template('<a href="<%= url %>"><%= text %></a>');
+templates.script = _.template('<script src="<%= source %>?v=<%= version %>"></script>');
+templates.input = _.template('<input class="<%= className %>" type="<%= type %>" name="<%= name %>" <%= extras %> />');
+
 module.exports = templates;

core/server/helpers/title.js

@@ -3,11 +3,10 @@
 //
 // Overrides the standard behaviour of `{[title}}` to ensure the content is correctly escaped
 
-var hbs             = require('express-hbs'),
-    title;
+var proxy = require('./proxy'),
+    SafeString = proxy.SafeString,
+    escapeExpression = proxy.escapeExpression;
 
-title = function () {
-    return new hbs.handlebars.SafeString(hbs.handlebars.Utils.escapeExpression(this.title || ''));
+module.exports = function title() {
+    return new SafeString(escapeExpression(this.title || ''));
 };
-
-module.exports = title;

core/server/helpers/twitter_url.js

@@ -6,11 +6,11 @@
 // We use the name twitter_url to match the helper for consistency:
 // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
 
-var socialUrls = require('../utils/social-urls'),
-    findKey    = require('./utils').findKey,
-    twitter_url;
+var proxy = require('./proxy'),
+    socialUrls = proxy.socialUrls,
+    findKey = proxy.utils.findKey;
 
-twitter_url = function twitter_url(username, options) {
+module.exports = function twitter_url(username, options) {
     if (!options) {
         options = username;
         username = findKey('twitter', this, options.data.blog);
@@ -22,5 +22,3 @@ twitter_url = function twitter_url(username, options) {
 
     return null;
 };
-
-module.exports = twitter_url;

core/server/helpers/url.js

@@ -4,16 +4,15 @@
 // Returns the URL for the current object scope i.e. If inside a post scope will return post permalink
 // `absolute` flag outputs absolute URL, else URL is relative
 
-var hbs            = require('express-hbs'),
-    getMetaDataUrl = require('../data/meta/url');
+var proxy = require('./proxy'),
+    SafeString = proxy.SafeString,
+    getMetaDataUrl = proxy.metaData.getMetaDataUrl;
 
-function url(options) {
+module.exports = function url(options) {
     var absolute = options && options.hash.absolute,
-        url = getMetaDataUrl(this, absolute);
+        outputUrl = getMetaDataUrl(this, absolute);
 
-    url = encodeURI(decodeURI(url));
+    outputUrl = encodeURI(decodeURI(outputUrl));
 
-    return new hbs.SafeString(url);
-}
-
-module.exports = url;
+    return new SafeString(outputUrl);
+};

core/server/helpers/utils.js

@@ -1,30 +0,0 @@
-var _       = require('lodash'),
-    utils;
-
-utils = {
-    assetTemplate: _.template('<%= source %>?v=<%= version %>'),
-    linkTemplate: _.template('<a href="<%= url %>"><%= text %></a>'),
-    scriptTemplate: _.template('<script src="<%= source %>?v=<%= version %>"></script>'),
-    inputTemplate: _.template('<input class="<%= className %>" type="<%= type %>" name="<%= name %>" <%= extras %> />'),
-    // @TODO this can probably be made more generic and used in more places
-    findKey: function findKey(key, object, data) {
-        if (object && _.has(object, key) && !_.isEmpty(object[key])) {
-            return object[key];
-        }
-
-        if (data && _.has(data, key) && !_.isEmpty(data[key])) {
-            return data[key];
-        }
-
-        return null;
-    },
-    parseVisibility: function parseVisibility(options) {
-        if (!options.hash.visibility) {
-            return ['public'];
-        }
-
-        return _.map(options.hash.visibility.split(','), _.trim);
-    }
-};
-
-module.exports = utils;

core/server/middleware/error-handler.js

@@ -4,9 +4,18 @@ var _ = require('lodash'),
     errors = require('../errors'),
     i18n = require('../i18n'),
     templates = require('../controllers/frontend/templates'),
+    escapeExpression = hbs.Utils.escapeExpression,
     _private = {},
     errorHandler = {};
 
+_private.createHbsEngine = function createHbsEngine() {
+    var engine = hbs.create();
+    // @TODO get rid of this after #8126
+    engine.registerHelper('asset', require('../helpers/asset'));
+
+    return engine.express4();
+};
+
 /**
  * This function splits the stack into pieces, that are then rendered using the following handlebars code:
  * ```
@@ -111,7 +120,7 @@ _private.HTMLErrorRenderer = function HTMLErrorRender(err, req, res, /*jshint un
     // It can be that something went wrong with the theme or otherwise loading handlebars
     // This ensures that no matter what res.render will work here
     if (_.isEmpty(req.app.engines)) {
-        req.app.engine('hbs', hbs.express3());
+        req.app.engine('hbs', _private.createHbsEngine());
     }
 
     res.render(templates.error(err.statusCode), templateData, function renderResponse(err, html) {
@@ -124,9 +133,9 @@ _private.HTMLErrorRenderer = function HTMLErrorRender(err, req, res, /*jshint un
         return res.status(500).send(
             '<h1>' + i18n.t('errors.errors.oopsErrorTemplateHasError') + '</h1>' +
             '<p>' + i18n.t('errors.errors.encounteredError') + '</p>' +
-            '<pre>' + hbs.handlebars.Utils.escapeExpression(err.message || err) + '</pre>' +
+            '<pre>' + escapeExpression(err.message || err) + '</pre>' +
             '<br ><p>' + i18n.t('errors.errors.whilstTryingToRender') + '</p>' +
-            err.statusCode + ' ' + '<pre>' + hbs.handlebars.Utils.escapeExpression(err.message || err) + '</pre>'
+            err.statusCode + ' ' + '<pre>' + escapeExpression(err.message || err) + '</pre>'
         );
     });
 };

core/server/themes/active.js

@@ -20,8 +20,7 @@ var _ = require('lodash'),
     join = require('path').join,
     themeConfig = require('./config'),
     config = require('../config'),
-    // @TODO: remove this require
-    hbs = require('express-hbs'),
+    engine = require('./engine'),
     // Current instance of ActiveTheme
     currentActiveTheme;
 
@@ -62,17 +61,13 @@ class ActiveTheme {
     }
 
     get partialsPath() {
-        return join(this.path, 'partials');
+        return this._partials.length > 0 ? join(this.path, 'partials') : null;
     }
 
     get mounted() {
         return this._mounted;
     }
 
-    hasPartials() {
-        return this._partials.length > 0;
-    }
-
     hasTemplate(templateName) {
         return this._templates.indexOf(templateName) > -1;
     }
@@ -82,17 +77,6 @@ class ActiveTheme {
     }
 
     mount(blogApp) {
-        let hbsOptions = {
-            partialsDir: [config.get('paths').helperTemplates],
-            onCompile: function onCompile(exhbs, source) {
-                return exhbs.handlebars.compile(source, {preventIndent: true});
-            }
-        };
-
-        if (this.hasPartials()) {
-            hbsOptions.partialsDir.push(this.partialsPath);
-        }
-
         // reset the asset hash
         // @TODO: set this on the theme instead of globally, or use proper file-based hash
         config.set('assetHash', null);
@@ -100,7 +84,7 @@ class ActiveTheme {
         blogApp.cache = {};
         // Set the views and engine
         blogApp.set('views', this.path);
-        blogApp.engine('hbs', hbs.express3(hbsOptions));
+        blogApp.engine('hbs', engine.configure(this.partialsPath));
 
         this._mounted = true;
     }

core/server/themes/engine.js

@@ -0,0 +1,27 @@
+var hbs = require('express-hbs'),
+    config = require('../config'),
+    instance = hbs.create();
+
+// @TODO think about a config option for this e.g. theme.devmode?
+if (config.get('env') !== 'production') {
+    instance.handlebars.logger.level = 0;
+}
+
+instance.escapeExpression = instance.handlebars.Utils.escapeExpression;
+
+instance.configure = function configure(partialsPath) {
+    var hbsOptions = {
+        partialsDir: [config.get('paths').helperTemplates],
+        onCompile: function onCompile(exhbs, source) {
+            return exhbs.handlebars.compile(source, {preventIndent: true});
+        }
+    };
+
+    if (partialsPath) {
+        hbsOptions.partialsDir.push(partialsPath);
+    }
+
+    return instance.express4(hbsOptions);
+};
+
+module.exports = instance;

core/server/themes/middleware.js

@@ -1,5 +1,5 @@
 var _  = require('lodash'),
-    hbs = require('express-hbs'),
+    hbs = require('./engine'),
     utils = require('../utils'),
     errors = require('../errors'),
     i18n = require('../i18n'),

core/server/utils/labs.js

@@ -1,7 +1,7 @@
 var settingsCache = require('../settings/cache'),
     _ = require('lodash'),
     Promise = require('bluebird'),
-    hbs = require('express-hbs'),
+    SafeString = require('../themes/engine').SafeString,
     errors = require('../errors'),
     logging = require('../logging'),
     i18n = require('../i18n'),
@@ -32,7 +32,7 @@ labs.enabledHelper = function enabledHelper(options, callback) {
 
     logging.error(new errors.GhostError(errDetails));
 
-    errString = new hbs.handlebars.SafeString(
+    errString = new SafeString(
         '<script>console.error("' + _.values(errDetails).join(' ') + '");</script>'
     );
 

core/server/utils/visibility.js

@@ -7,7 +7,7 @@ var _ = require('lodash');
  * @param {Function} [fn]
  * @returns {Array|Object} filtered items
  */
-module.exports = function visibilityFilter(items, visibility, explicit, fn) {
+module.exports.filter = function visibilityFilter(items, visibility, explicit, fn) {
     var memo = _.isArray(items) ? [] : {};
 
     if (_.includes(visibility, 'all')) {
@@ -27,3 +27,11 @@ module.exports = function visibilityFilter(items, visibility, explicit, fn) {
         return memo;
     }, memo);
 };
+
+module.exports.parser = function visibilityParser(options) {
+    if (!options.hash.visibility) {
+        return ['public'];
+    }
+
+    return _.map(options.hash.visibility.split(','), _.trim);
+};

core/test/unit/apps_spec.js

@@ -4,7 +4,7 @@ var should = require('should'),
     EventEmitter = require('events').EventEmitter,
     _ = require('lodash'),
     Promise = require('bluebird'),
-    helpers = require('../../server/helpers'),
+    helpers = require('../../server/helpers/register'),
     filters = require('../../server/filters'),
     i18n = require('../../server/i18n'),
 
@@ -218,7 +218,7 @@ describe('Apps', function () {
         });
 
         it('allows helper registration with permission', function () {
-            var registerSpy = sandbox.spy(helpers, 'registerThemeHelper'),
+            var registerSpy = sandbox.stub(helpers, 'registerThemeHelper'),
                 appProxy = new AppProxy({
                     name: 'TestApp',
                     permissions: {
@@ -234,7 +234,7 @@ describe('Apps', function () {
         });
 
         it('does not allow helper registration without permission', function () {
-            var registerSpy = sandbox.spy(helpers, 'registerThemeHelper'),
+            var registerSpy = sandbox.stub(helpers, 'registerThemeHelper'),
                 appProxy = new AppProxy({
                     name: 'TestApp',
                     permissions: {
@@ -255,7 +255,7 @@ describe('Apps', function () {
         });
 
         it('does allow INTERNAL app to register helper without permission', function () {
-            var registerSpy = sandbox.spy(helpers, 'registerThemeHelper'),
+            var registerSpy = sandbox.stub(helpers, 'registerThemeHelper'),
                 appProxy = new AppProxy({
                     name: 'TestApp',
                     permissions: {},

core/test/unit/server_helpers/date_spec.js

@@ -29,7 +29,7 @@ describe('{{date}} helper', function () {
             var rendered = helpers.date.call({published_at: d}, context);
 
             should.exist(rendered);
-            rendered.should.equal(moment(d).tz(timezones).format(format));
+            String(rendered).should.equal(moment(d).tz(timezones).format(format));
         });
     });
 
@@ -57,7 +57,7 @@ describe('{{date}} helper', function () {
             var rendered = helpers.date.call({published_at: d}, context);
 
             should.exist(rendered);
-            rendered.should.equal(moment(d).tz(timezones).from(timeNow));
+            String(rendered).should.equal(moment(d).tz(timezones).from(timeNow));
         });
     });
 });

core/test/unit/server_helpers/foreach_spec.js

@@ -3,7 +3,8 @@ var should = require('should'), // jshint ignore:line
     _ = require('lodash'),
 
 // Stuff we are testing
-    helpers = require('../../../server/helpers'),
+    helpers = require.main.require('core/server/helpers'),
+    handlebars = require.main.require('core/server/themes/engine').handlebars,
 
     sandbox = sinon.sandbox.create();
 
@@ -250,8 +251,7 @@ describe('{{#foreach}} helper', function () {
     });
 
     describe('(compile)', function () {
-        var handlebars = require('express-hbs').handlebars,
-            objectHash = {
+        var objectHash = {
                 posts: {
                     first: {title: 'first'},
                     second: {title: 'second'},

core/test/unit/server_helpers/ghost_foot_spec.js

@@ -3,7 +3,8 @@ var should = require('should'), // jshint ignore:line
 
 // Stuff we are testing
     helpers = require('../../../server/helpers'),
-    settingsCache = require('../../../server/settings/cache'),
+    proxy = require('../../../server/helpers/proxy'),
+    settingsCache = proxy.settingsCache,
 
     sandbox = sinon.sandbox.create();
 

core/test/unit/server_helpers/ghost_head_spec.js

@@ -5,9 +5,10 @@ var should = require('should'), // jshint ignore:line
     moment = require('moment'),
     configUtils = require('../../utils/configUtils'),
     helpers = require('../../../server/helpers'),
-    api = require('../../../server/api'),
-    labs = require('../../../server/utils/labs'),
-    settingsCache = require('../../../server/settings/cache'),
+    proxy = require('../../../server/helpers/proxy'),
+    settingsCache = proxy.settingsCache,
+    api = proxy.api,
+    labs = proxy.labs,
 
     sandbox = sinon.sandbox.create();
 

core/test/unit/server_helpers/navigation_spec.js

@@ -1,5 +1,5 @@
 var should = require('should'),
-    hbs = require('express-hbs'),
+    hbs = require('../../../server/themes/engine'),
 
     configUtils = require('../../utils/configUtils'),
     path = require('path'),

core/test/unit/server_helpers/pagination_spec.js

@@ -1,5 +1,5 @@
 var should = require('should'), // jshint ignore:line
-    hbs = require('express-hbs'),
+    hbs = require('../../../server/themes/engine'),
     configUtils = require('../../utils/configUtils'),
     path = require('path'),
 

core/test/unit/server_helpers_index_spec.js

@@ -1,7 +1,7 @@
 // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
 var should = require('should'), // jshint ignore:line
     _ = require('lodash'),
-    hbs = require('express-hbs'),
+    hbs = require.main.require('core/server/themes/engine'),
 
     // Stuff we are testing
     helpers = require.main.require('core/server/helpers');
@@ -22,7 +22,7 @@ describe('Helpers', function () {
         });
 
         // This will work when we finish refactoring
-        it.skip('should have exactly the right helpers', function () {
+        it('should have exactly the right helpers', function () {
             var foundHelpers, missingHelpers, unexpectedHelpers;
 
             foundHelpers = _.keys(hbs.handlebars.helpers);

core/test/unit/server_helpers_template_spec.js

@@ -1,8 +1,8 @@
 var should = require('should'),
-    hbs = require('express-hbs'),
+    hbs = require.main.require('core/server/themes/engine'),
 
     // Stuff we are testing
-    template = require('../../server/helpers/template');
+    template = require.main.require('core/server/helpers/template');
 
 describe('Helpers Template', function () {
     it('can execute a template', function () {

core/test/unit/themes/active_spec.js

@@ -1,10 +1,10 @@
 var should = require('should'), // jshint ignore:line
     sinon = require('sinon'),
-    hbs = require('express-hbs'),
 
     config = require('../../../server/config'),
     // is only exposed via themes.getActive()
     activeTheme = require('../../../server/themes/active'),
+    engine = require('../../../server/themes/engine'),
 
     sandbox = sinon.sandbox.create();
 
@@ -15,11 +15,11 @@ describe('Themes', function () {
 
     describe('Active', function () {
         describe('Mount', function () {
-            var hbsStub, configStub,
+            var engineStub, configStub,
                 fakeBlogApp, fakeLoadedTheme, fakeCheckedTheme;
 
             beforeEach(function () {
-                hbsStub = sandbox.stub(hbs, 'express3');
+                engineStub = sandbox.stub(engine, 'configure');
                 configStub = sandbox.stub(config, 'set');
 
                 fakeBlogApp = {
@@ -58,11 +58,9 @@ describe('Themes', function () {
                 fakeBlogApp.set.calledOnce.should.be.true();
                 fakeBlogApp.set.calledWith('views', 'my/fake/theme/path').should.be.true();
 
-                // Check handlebars was initialised correctly
-                hbsStub.calledOnce.should.be.true();
-                hbsStub.firstCall.args[0].should.be.an.Object().and.have.property('partialsDir');
-                hbsStub.firstCall.args[0].partialsDir.should.be.an.Array().with.lengthOf(2);
-                hbsStub.firstCall.args[0].partialsDir[1].should.eql('my/fake/theme/path/partials');
+                // Check handlebars was configured correctly
+                engineStub.calledOnce.should.be.true();
+                engineStub.calledWith('my/fake/theme/path/partials').should.be.true();
 
                 // Check the theme is now mounted
                 activeTheme.get().mounted.should.be.true();
@@ -91,10 +89,9 @@ describe('Themes', function () {
                 fakeBlogApp.set.calledOnce.should.be.true();
                 fakeBlogApp.set.calledWith('views', 'my/fake/theme/path').should.be.true();
 
-                // Check handlebars was initialised correctly
-                hbsStub.calledOnce.should.be.true();
-                hbsStub.firstCall.args[0].should.be.an.Object().and.have.property('partialsDir');
-                hbsStub.firstCall.args[0].partialsDir.should.have.lengthOf(1);
+                // Check handlebars was configured correctly
+                engineStub.calledOnce.should.be.true();
+                engineStub.calledWith().should.be.true();
 
                 // Check the theme is now mounted
                 activeTheme.get().mounted.should.be.true();

core/test/unit/themes/middleware_spec.js

@@ -1,6 +1,6 @@
 var should = require('should'), // jshint ignore:line
     sinon = require('sinon'),
-    hbs = require('express-hbs'),
+    hbs = require('../../../server/themes/engine'),
 
     themes = require('../../../server/themes'),
     // is only exposed via themes.getActive()