为Ghost Blog添加访问/阅读计数

    var Promise = require('bluebird');
    var self = this;
    //计数器
    var urlCounter;
    //数据库配置
    var knex = require('knex')({
      client: 'sqlite3',
      connection: {
        filename: "./view_counter.db"
      }
    });
    //初始化操作，读取关机之前的数据.
    initDB();
    
    
    //计数器加一
    function countViewer(appServer){
    	appServer.use('/management/count',function(req,res,next){
    		var visiturl = req.query.slug;
    		if(visiturl!=undefined && visiturl!=null && visiturl!=''){
    			if(urlCounter[visiturl] == undefined){
    				urlCounter[visiturl] =1;
    			}else{
    				var count = urlCounter[visiturl];
    				urlCounter[visiturl] = ++count;
    				//console.log(visiturl + ':' + count);
    			}
    		}
    		res.status(200).end();
    	});
    	
    	appServer.use('/management/counter',function(req,res,next){
    		//var reqBody = req.body;
    		//console.log(reqBody);
    		var visitUrlStr = req.query.slug;
    		if(visitUrlStr== null || visitUrlStr==''){
    			res.status(200).end();
    		}else{
    			var result = [];
    			var visitUrls = visitUrlStr.split(',');
    			Promise.map(visitUrls,function(visitUrl){
    				var vCount = urlCounter[visitUrl];
    				if(vCount != undefined){
    					var row = {};
    					row.id = visitUrl;
    					row.value = vCount.toString();
    					result.push(row);
    				}
    			}).then(function(){
    				res.json(result);
    			});
    		}
    	});
    	
    	appServer.use('/management/counter/all',function(req,res,next){
    		res.send(urlCounter);
    	});
    }
    
    //根据url获取页面访问次数
    function getViewerCount(slug){
    	if(urlCounter[visiturl]==undefined){
    		return 0;
    	}else{
    		return urlCounter[visiturl];
    	}
    }
    
    //初始化db
    function initDB(){
    	knex.schema.createTableIfNotExists('viewer_counter',function(table){
    		table.string('url');
    		table.integer('visit_count');
    	}).then(function(result){
    		//初始化数据
    		loadLastData();
    		//计时器，负责入库
    		setTimeout(function(){
    			saveViewerCount();
    		},60000);
    	});
    }
    
    //初始化计数器
    function loadLastData(){
    	//获取上一次的数据
    	urlCounter = {};
    	knex.select('url','visit_count').table('viewer_counter').then(function(rows) {
    		rows.forEach(function(row){
    			debugger;
    			//console.log(row.url + ':' + row.visit_count);
    			urlCounter[row.url] = row.visit_count;
    		});
    	});
    }
    
    //保存入库
    function saveViewerCount(){
    	//console.log('saving....');
    	var keys = Object.keys(urlCounter);
    	knex.transaction(function(trx){
    		debugger;
    		knex('viewer_counter').transacting(trx).del()
    		.then(function(){
    			return Promise.map(keys,function(rowKey){
    				//console.log(rowKey + ':'+ urlCounter[rowKey]);
    				var info ={'url':rowKey,'visit_count':urlCounter[rowKey]};
    				return knex.insert(info).into('viewer_counter').transacting(trx);
    			});
    		}).then(trx.commit).catch(trx.rollback);
    	}).then(function(insert){
    		//console.log(insert.length + ' url saved.');
    		//等insert完成之后再开始下一次定时器
    		setTimeout(function(){
    			saveViewerCount();
    		},60000);
    	}).catch(function(error) {
    		console.error(error);
    				//等insert完成之后再开始下一次定时器
    		setTimeout(function(){
    			saveViewerCount();
    		},60000);
    	});
    }
    
    module.exports.countViewer=countViewer;
    module.exports.getViewerCount=getViewerCount;

	var viewerCounter = require('./viewer-counter');
    // Create our parent express app instance.
    parentApp = express();//这句话其实是Ghost原有的代码
    viewerCounter.countViewer(parentApp);

      <script type='text/javascript'>
    	function addVisitCount(){
    		$.ajax({
    			url:'/management/count?slug={{slug}}',
    			type:'get',
    			success:function(data){
    				console.log('success');
    			}
    		});
    	}
    	//停留3秒
    	setTimeout(function(){
    		addVisitCount();
    	},3000);
    </script>

    <script type='text/javascript'>
	    //获取文章的url计数
    var articleSlugs = [];
    var articleLinks = $('article .post-view-count');
    for(var i=0;i<articleLinks.length;i++){
    	articleSlugs.push($(articleLinks[i]).attr('id'));
    }
    var slug = encodeURI(articleSlugs.toString());
    $.ajax({
    	url:'/management/counter?slug='+slug,
    	type:'GET',
    	success:function(data){
    		if(data!='' && data.length >0){
    			$(data).each(function(idx,ele){
    				$('#' + ele.id).text(ele.value);
    			});
    		}
    	}
    });
    </script>

<footer class="post-meta">
    {{#if author.image}}<img class="author-thumb" src="{{author.image}}" alt="{{author.name}}" nopin="nopin" />{{/if}}
    {{author}}
    {{tags prefix=" on "}}
    <time class="glyphicon glyphicon-calendar post-date" datetime="{{date format="YYYY-MM-DD"}}">{{date format="YYYY-MM-DD"}}</time>
    <span id='{{slug}}' class="glyphicon glyphicon-eye-open post-view-count">0</span>
</footer>

    .post-view-count{
    	font-size:1.3rem;
    	padding-left:12px;
    	margin-left:8px;
    	display:inline-block;
    	white-space:nowrap;
    }