Merge pull request #1978 from maple3142/master

Feature: firestore visitor counter

_config.yml

@@ -432,14 +432,14 @@ gitment:
 #           Evernote,Friendfeed,Vkontakte,Odnoklassniki,Mailru
 needmoreshare2:
   enable: false
-  postbottom: 
+  postbottom:
     enable: false
     options:
       iconStyle: box
       boxForm: horizontal
       position: bottomCenter
       networks: Weibo,Wechat,Douban,QQZone,Twitter,Facebook
-  float: 
+  float:
     enable: false
     options:
       iconStyle: box
@@ -522,6 +522,15 @@ leancloud_visitors:
   app_id: #<app_id>
   app_key: #<app_key>
 
+# Another tool to show number of visitors to each article.
+# visit https://console.firebase.google.com/u/0/ to get apiKey and projectId
+# visit https://firebase.google.com/docs/firestore/ to get more information about firestore
+firestore:
+  enable: false
+  collection: articles #required, a string collection name to access firestore database
+  apiKey: #required
+  projectId: #required
+
 # Show PV/UV of the website/page with busuanzi.
 # Get more information on http://ibruce.info/2015/04/04/busuanzi/
 busuanzi_count:

layout/_layout.swig

@@ -81,6 +81,7 @@
   {% include '_third-party/comments/index.swig' %}
   {% include '_third-party/search/index.swig' %}
   {% include '_third-party/analytics/lean-analytics.swig' %}
+  {% include '_third-party/analytics/firestore.swig' %}
   {% include '_third-party/seo/baidu-push.swig' %}
   {% include '_third-party/needsharebutton.swig' %}
   {% include '_third-party/rating.swig' %}

layout/_third-party/analytics/firestore.swig

@@ -0,0 +1,54 @@
+{% if theme.firestore.enable %}
+<script src="https://www.gstatic.com/firebasejs/4.6.0/firebase.js"></script>
+<script src="https://www.gstatic.com/firebasejs/4.6.0/firebase-firestore.js"></script>
+<script>
+	(function(){
+		var title='{{ page.title }}'
+		if(title){
+
+			firebase.initializeApp({
+				apiKey: '{{ theme.firestore.apiKey }}',
+				projectId: '{{ theme.firestore.projectId }}'
+			})
+
+
+			var db = firebase.firestore()
+			var articles=db.collection('{{ theme.firestore.collection }}')
+			var doc=articles.doc(title)
+
+			doc.get().then(function(d){
+				var count
+				if(!d.exists){ //has no data, initialize count
+					doc.set({
+						count: 1
+					})
+					count=1
+				}
+				else{ //has data
+					count=d.data().count
+					if(!(window.localStorage&&window.localStorage.getItem(title))){ //if first view this article
+						doc.set({ //increase count
+							count: count+1
+						})
+            count++
+					}
+				}
+        if(window.localStorage){ //mark as visited
+          localStorage.setItem(title,true)
+        }
+
+        //append to meta
+				$('.post-meta').append(
+          $('<span>').addClass('post-visitors-count').append(
+            $('<span>').addClass('post-meta-divider').text('|')
+          ).append(
+            $('<span>').addClass('post-meta-item-icon').append(
+              $('<i>').addClass('fa fa-users')
+            )
+          ).append($('<span>').text('{{ __("post.visitors")}} '+count))
+        )
+			})
+		}
+	})()
+</script>
+{% endif %}