Add banner support

app/assets/javascripts/modules/global-bar.js

@@ -0,0 +1,58 @@
+/*
+  Global bar
+
+  Manages count of how many times a global bar has been seen
+  using cookies.
+*/
+(function(Modules) {
+  "use strict";
+
+  Modules.GlobalBar = function() {
+    this.start = function($el) {
+      var GLOBAL_BAR_SEEN_COOKIE = "global_bar_seen",
+          count = viewCount();
+
+      $el.on('click', '.dismiss', hide);
+
+      if ($el.is(':visible')) {
+        incrementViewCount(count);
+        track('Viewed');
+      }
+
+      function hide(evt) {
+        $el.hide();
+        GOVUK.setCookie(GLOBAL_BAR_SEEN_COOKIE, 999, {days: 84});
+        track('Manually dismissed');
+        $('html').removeClass('show-global-bar');
+        evt.preventDefault();
+      }
+
+      function incrementViewCount(count) {
+        count = count + 1;
+        GOVUK.setCookie(GLOBAL_BAR_SEEN_COOKIE, count, {days: 84});
+
+        if (count == 2) {
+          track('Automatically dismissed');
+        }
+      }
+
+      function viewCount() {
+        var viewCountCookie = GOVUK.getCookie(GLOBAL_BAR_SEEN_COOKIE),
+            viewCount = parseInt(viewCountCookie, 10);
+
+        if (isNaN(viewCount)) {
+          viewCount = 0;
+        }
+
+        return viewCount;
+      }
+
+      function track(action) {
+        if (GOVUK.analytics && typeof GOVUK.analytics.trackEvent === "function") {
+          GOVUK.analytics.trackEvent('Global bar', action, {nonInteraction: 1});
+        }
+      }
+    };
+  };
+
+})(window.GOVUK.Modules);

app/assets/javascripts/start-modules.js

@@ -1,4 +1,5 @@
 // = require govuk/modules
+// = require modules/global-bar
 // = require modules/sticky-element-container
 // = require modules/toggle
 // = require modules/track-click

app/assets/javascripts/surveys.js

@@ -158,6 +158,7 @@
       if (userSurveys.canShowAnySurvey()) {
         var activeSurvey = userSurveys.getActiveSurvey(userSurveys.defaultSurvey, userSurveys.smallSurveys)
         if (activeSurvey !== undefined) {
+          $('#global-bar').hide(); // Hide global bar if one is showing
           userSurveys.displaySurvey(activeSurvey)
         }
       }

app/assets/stylesheets/helpers/_header.scss

@@ -341,3 +341,48 @@
     margin-right: .5em;
   }
 }
+
+
+.show-global-bar #global-header-bar {
+  display: none;
+}
+
+.global-bar {
+  background-color: #BFE3E0;
+  display: none;
+  margin-bottom: 15px;
+  padding: 15px 0;
+
+  .show-global-bar & {
+    display: block;
+  }
+
+  .global-bar-message-container {
+    @include core-19;
+    @extend %site-width-container;
+    position: relative;
+
+    @include media(tablet) {
+      .dismiss {
+        position: absolute;
+        right: 0;
+        top: 0;
+      }
+    }
+  }
+
+  .global-bar-message {
+    margin-bottom: 0;
+    margin-top: 0;
+
+    @include media(tablet) {
+      max-width: 66.67%;
+    }
+
+    .global-bar-title {
+      display: block;
+      font-weight: 700;
+      margin-right: 10px;
+    }
+  }
+}

app/views/notifications/_global_bar.html.erb

@@ -0,0 +1,29 @@
+<%
+  show_global_bar ||= false # Toggles the appearance of the global bar
+  title = "The title"
+  information = "Some information about something"
+  link_href = "https://www.gov.uk/"
+  link_text = %Q(More information<span class="visually-hidden"> about this</span>).html_safe
+-%>
+<% if show_global_bar %>
+  <% content_for :head do %>
+    <!--[if gt IE 7]><!-->
+    <script>!function(t){"use strict";function e(){return!/^\/register-to-vote|^\/done/.test(window.location.pathname)}function n(){var e=t.cookie.match("(?:^|[ ;])global_bar_seen=([0-9]+)");return e?parseInt(e.pop(),10)<3:!0}var o=t.documentElement;e()&&n()&&(o.className=o.className.concat(" show-global-bar"))}(document);</script>
+    <!--<![endif]-->
+  <% end %>
+  <!--[if gt IE 7]><!-->
+  <div id="global-bar" class="global-bar" data-module="global-bar" class="dont-print">
+    <div class="global-bar-message-container">
+    <p class="global-bar-message">
+      <span class="global-bar-title"><%= title %></span>
+      <%= information %>
+      <%= link_to(link_text, link_href, rel: "external noreferrer") %>
+    </p>
+    <a href="#hide-message"
+       class="dismiss"
+       role="button"
+       aria-controls="global-bar">Hide&nbsp;message</a>
+    </div>
+  </div>
+  <!--<![endif]-->
+<% end %>

app/views/root/_base.html.erb

@@ -30,6 +30,8 @@
 <% end %>
 
 <% content_for :content do %>
+  <%= render "notifications/global_bar" %>
+
   <div id="wrapper" class="group">
     <%= yield :wrapper_content %>
   </div>

doc/global-banner.md

@@ -0,0 +1,16 @@
+## Global banner
+
+A site-wide banner can be activated to convey important information on GOV.UK which is not deemed emergency level information.
+The file `app/views/notifications/_global_bar.html.erb` contains the necessary minified JS and markup to activate and render the banner.
+
+### Activating the global banner
+
+In `app/views/notifications/_global_bar.html.erb`
+
+1. Update the variables `title`, `information`, `link_href` and `link_text` with the relevant info.
+2. Update the `show_global_bar` variable to `true`
+3. Deploy static
+
+The usual rules apply with static template caching.
+
+![screenshot](/doc/global-banner.png?raw=true)

spec/javascripts/global-bar-class-toggle.spec.js

@@ -0,0 +1,133 @@
+describe("toggling a global bar HTML class based on cookie", function () {
+  var root = window;
+
+  /**
+   * The global bar needs to be activated early in page loading to prevent
+   * a flash of unstyled content, to do this we need to minify and inline
+   * the activation logic into the page head.
+   * This spec runs tests against both the full and minified sources of the
+   * activation JS because minification is not automated.
+   */
+  function globalBarSource(fakeWindow) {
+    var window = fakeWindow || root;
+
+    /* begin minify */
+
+    (function (document) {
+      "use strict"
+      var documentElement = document.documentElement;
+      if (urlPermitsShow() && viewCountPermitsShow()) {
+        documentElement.className = documentElement.className.concat(' show-global-bar');
+      }
+
+      function urlPermitsShow() {
+        return !/^\/register-to-vote|^\/done/.test(window.location.pathname);
+      }
+
+      function viewCountPermitsShow() {
+        var c = document.cookie.match('(?:^|[ ;])global_bar_seen=([0-9]+)');
+        if (!c) {
+          return true;
+        }
+
+        return parseInt(c.pop(), 10) < 3;
+      }
+    })(document);
+
+    /* end minify */
+  }
+
+
+  /**
+   * This is the minified version of the function above 'globalBarSource',
+   * when developing and testing updates and features,
+   * changes should be mirrored here manually.
+   * Only the code between the 'begin/end minify' comments should be copied.
+   */
+  function globalBarMinified(fakeWindow) {
+    var window = fakeWindow || root;
+
+    /* begin minify */
+    !function(t){"use strict";function e(){return!/^\/register-to-vote|^\/done/.test(window.location.pathname)}function n(){var e=t.cookie.match("(?:^|[ ;])global_bar_seen=([0-9]+)");return e?parseInt(e.pop(),10)<3:!0}var o=t.documentElement;e()&&n()&&(o.className=o.className.concat(" show-global-bar"))}(document);
+    /* end minify */
+  }
+
+  afterEach(function() {
+    $('html').removeClass('show-global-bar');
+    deleteAllCookies();
+
+    function deleteAllCookies() {
+      var cookies = document.cookie.split(";");
+
+      for (var i = 0; i < cookies.length; i++) {
+        var cookie = cookies[i];
+        var eqPos = cookie.indexOf("=");
+        var name = eqPos > -1 ? cookie.substr(0, eqPos) : cookie;
+        document.cookie = name + "=;expires=Thu, 01 Jan 1970 00:00:00 GMT";
+      }
+    }
+  });
+
+  describe('when running the full source', function() {
+    runTests(globalBarSource);
+  });
+
+  describe('when running the minified source', function() {
+    runTests(globalBarMinified);
+  });
+
+  function runTests(globalBarFn) {
+    it("shows when no cookie is set", function() {
+      expectGlobalBarToBeHidden();
+      globalBarFn();
+      expectGlobalBarToShow();
+    });
+
+    it("does not show when bar has been seen 3 times", function() {
+      GOVUK.setCookie('global_bar_seen', 3);
+      expectGlobalBarToBeHidden();
+      globalBarFn();
+      expectGlobalBarToBeHidden();
+    });
+
+    it("shows when the bar has been seen 2 times", function() {
+      GOVUK.setCookie('global_bar_seen', '2');
+      globalBarFn();
+      expectGlobalBarToShow();
+    });
+
+    it("shows when the bar has been seen 2 times and there are lots of cookies", function() {
+      GOVUK.setCookie('global_bar_thing', '10');
+      GOVUK.setCookie('seen_cookie_message', 'true');
+      GOVUK.setCookie('global_bar_seen', '2');
+      GOVUK.setCookie('is_global_bar_seen', '8');
+      GOVUK.setCookie('_ua', '1234873487');
+      globalBarFn();
+      expectGlobalBarToShow();
+    });
+
+    it("shows when the cookie value is not a parseable number", function() {
+      GOVUK.setCookie('global_bar_seen', 'foo_bar2');
+      globalBarFn();
+      expectGlobalBarToShow();
+    });
+
+    it("does not show on register to vote pages", function() {
+      globalBarFn({location: {pathname: '/register-to-vote'}});
+      expectGlobalBarToBeHidden();
+    });
+
+    it("does not show on done pages", function() {
+      globalBarFn({location: {pathname: '/done'}});
+      expectGlobalBarToBeHidden();
+    });
+  }
+
+  function expectGlobalBarToShow() {
+    expect($('html').is('.show-global-bar')).toBe(true);
+  }
+
+  function expectGlobalBarToBeHidden() {
+    expect($('html').is('.show-global-bar')).toBe(false);
+  }
+});