Add copy versioned url

Closes gh-281

Author: rwinch

src/css/breadcrumbs.css

@@ -27,7 +27,8 @@
   }
 }
 
-a + .breadcrumbs {
+a + .breadcrumbs,
+button + .breadcrumbs {
   padding-left: 0.05rem;
 }
 
@@ -52,3 +53,27 @@ a + .breadcrumbs {
 .breadcrumbs li:last-of-type::after {
   content: none;
 }
+
+#copy-url {
+  content: "";
+  background-image: url(../img/url.svg);
+  background-repeat: no-repeat;
+  background-size: contain;
+  width: 20px;
+  height: 20px;
+  margin-right: 5px;
+  vertical-align: middle;
+  display: inline-block;
+}
+
+#copy-url.copied {
+  background-image: url(../img/octicons-16.svg#view-copy);
+}
+
+#copy-url::after {
+  content: none;
+}
+
+#copy-url:hover {
+  cursor: pointer;
+}

src/helpers/versioned_url.js

@@ -0,0 +1,12 @@
+'use strict'
+
+module.exports = (siteUrl, versionSegment, url) => {
+  if (!url) {
+    // occurs with stock pages like 404.html
+    return url
+  } else if (url.startsWith(`/${versionSegment}/`)) {
+    return `${siteUrl}${url}`
+  } else {
+    return `${siteUrl}/${versionSegment}${url}`
+  }
+}

src/img/url.svg

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2021 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the 'License');
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an 'AS IS' BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+;(function () {
+  'use strict'
+
+  var copyUrl = document.getElementById('copy-url')
+  if (!copyUrl) return
+
+  copyUrl.addEventListener('click', function (event) {
+    var versionedUrl = document.querySelector('meta[name="versioned-url"]')?.content
+    window.navigator.clipboard.writeText(versionedUrl)
+    this.classList.add('copied')
+    setTimeout(() => {
+      this.classList.remove('copied')
+    }, 1500)
+  })
+})()

src/js/08-copy-versioned-url.js

@@ -2,6 +2,7 @@
   <nav class="breadcrumbs" aria-label="breadcrumbs">
     {{#if page.breadcrumbs}}
     <ul>
+      <li id="copy-url" title="Copy versioned URL"></li>
       {{#with page.componentVersion}}
       {{#if (and ./title (ne ./title @root.page.breadcrumbs.0.content))}}
       <li><a href="{{{relativize ./url}}}">{{{./title}}}</a></li>

src/partials/breadcrumbs.hbs

@@ -2,5 +2,6 @@
     <meta name="antora-ui-version" content="@@antora-ui-version"> {{!-- replaced by the gulp build --}}
     <meta name="version" content="{{{page.version}}}">
     <meta name="generation" content="{{{page.componentVersion.versionSegment}}}">
+    <meta name="versioned-url" content="{{{versioned_url site.url page.componentVersion.versionSegment page.url}}}">
     <meta name="component" content="{{{page.component.name}}}">
     <meta name="latest-version" content="{{~#if (and page.latest (eq page.url page.latest.url))}}true{{~else}}false{{~/if}}">

src/partials/head-meta.hbs

@@ -0,0 +1,24 @@
+/* eslint-env mocha */
+'use strict'
+
+const { expect } = require('./harness')
+const versionedUrl = require('../src/helpers/versioned_url.js')
+
+describe('versioned_url', () => {
+  const siteUrl = 'https://docs.spring.io/spring-security/reference'
+  const versionSegment = '7.0'
+  const url = '/index.html'
+  it('when url does not contain version segment', () => {
+    const result = versionedUrl(siteUrl, versionSegment, url)
+    expect(result).is.eql('https://docs.spring.io/spring-security/reference/7.0/index.html')
+  })
+  it('when url does contain version segment', () => {
+    const result = versionedUrl(siteUrl, versionSegment, `/${versionSegment}${url}`)
+    expect(result).is.eql('https://docs.spring.io/spring-security/reference/7.0/index.html')
+  })
+  it('when url undefined', () => {
+    // happens on 404.html
+    const result = versionedUrl(siteUrl, versionSegment, undefined)
+    expect(result).is.eql(undefined)
+  })
+})