Cayley图数据库的可视化(Visualize)
引入
在文章Cayley图数据库的简介及使用中,我们已经了解了Cayley图数据库的安装、数据导入以及进行查询等。
Cayley图数据库是Google开发的开源图数据库,虽然功能还没有Neo4J来得那么强大,但也有很多新的功能等待着我们去探索。本文将继续上篇文章的旅程,给读者介绍如何在Cayley图数据库中实现查询结果的可视化。
下面,让我们一起来探究Cayley的奥秘吧~
查询结果可视化
Cayley图数据库的查询语句的参考网址为:https://github.com/cayleygraph/cayley/blob/master/docs/GizmoAPI.md 。 若想实现查询结果的可视化,则需要使用Tag()函数,返回的结果样式应当如下:
[ { "source": "node1", "target": "node2" }, { "source": "node1", "target": "node3" }, ]
即返回的结果中对节点会打上Tag,source为来源,颜色为蓝色,target为目的地,颜色为橙色。
我们使用的数据仍来自文章Cayley图数据库的简介及使用 。 首先导入数据:
./cayley load -c cayley_example.yml -i data/China_Movie.nq
接着启动查询语句的web界面:
./cayley http -i ./data/China_Movie.nq -d memstore --host=:64210
在浏览器中输入网址:http://localhost:64210 ,选择Visualize,
输入命令:
g.V('<沈腾>').Tag("source").Out('<ACT_IN>').Tag("target").All();
就能能到关系图的可视化结果了,如下:
接着我们来查看某个实体的所有属性及属性值,输入的命令如下:
var eq = "<流浪地球>"; var attrs = g.V(eq).OutPredicates().ToArray(); values = new Array(); for (i in attrs) { var value = g.V(eq).Out(attrs[i]).ToValue(); values[i] = value; } var s = new Array(); for (i in attrs) { var key_val_json = new Object(); key_val_json["id"] = values[i]; key_val_json["source"] = eq; key_val_json["target"]= attrs[i]+":"+values[i]; s[i] = key_val_json; } for (i =0; i< s.length; i++) { g.Emit(s[i]); }
出来的图如下:
这样我们就实现了Cayley图数据库的可视化,但是效果一般,而且不支持对边赋值,因此无法在边上显示关系。
利用D3.js实现可视化展示
利用D3.js,我们可以把查询到的结果,自己来画关系图。笔者主要参考的项目的Github地址为: https://github.com/ownthink/KG-View/blob/master/index.html 。我们只需要将查询到的结果复制粘贴到该HTML文件中即可。还是以《流浪地球》的所有属性及属性值为例,查询的命令如下:
var eq = "<流浪地球>"; var attrs = g.V(eq).OutPredicates().ToArray(); values = new Array(); for (i in attrs) { var value = g.V(eq).Out(attrs[i]).ToValue(); values[i] = value; } var s = new Array(); for (i in attrs) { var key_val_json = new Object(); key_val_json["source"] = eq; key_val_json["rela"] = attrs[i]; key_val_json["target"] = values[i]; key_val_json["type"] = "resolved"; s[i] = key_val_json; } for (i =0; i< s.length; i++) { g.Emit(s[i]); }
返回的结果如下:
{ "result": [ { "rela": "<ISA>", "source": "<流浪地球>", "target": "<Movie>", "type": "resolved" }, { "rela": "<rank>", "source": "<流浪地球>", "target": "2", "type": "resolved" }, { "rela": "<src>", "source": "<流浪地球>", "target": "/item/%E6%B5%81%E6%B5%AA%E5%9C%B0%E7%90%83", "type": "resolved" }, { "rela": "<box_office>", "source": "<流浪地球>", "target": "40.83亿", "type": "resolved" }, { "rela": "<avg_price>", "source": "<流浪地球>", "target": "46", "type": "resolved" }, { "rela": "<avg_people>", "source": "<流浪地球>", "target": "50", "type": "resolved" }, { "rela": "<begin_date>", "source": "<流浪地球>", "target": "2019.02.05", "type": "resolved" } ] }
将result的结果数组复制粘贴至index.html文件,内容如下:
<!DOCTYPE html> <meta charset="utf-8"> <style>.link { fill: none; stroke: #666; stroke-width: 1.5px;}#licensing { fill: green;}.link.licensing { stroke: green;}.link.resolved { stroke-dasharray: 0,2 1;}circle { fill: #ccc; stroke: #333; stroke-width: 1.5px;}text { font: 12px Microsoft YaHei; pointer-events: none; text-shadow: 0 1px 0 #fff, 1px 0 0 #fff, 0 -1px 0 #fff, -1px 0 0 #fff;}.linetext { font-size: 12px Microsoft YaHei;}</style> <body> <script src="https://d3js.org/d3.v3.min.js"></script> <script> var links = [ { "rela": "<ISA>", "source": "<流浪地球>", "target": "<Movie>", "type": "resolved" }, { "rela": "<rank>", "source": "<流浪地球>", "target": "2", "type": "resolved" }, { "rela": "<src>", "source": "<流浪地球>", "target": "/item/%E6%B5%81%E6%B5%AA%E5%9C%B0%E7%90%83", "type": "resolved" }, { "rela": "<box_office>", "source": "<流浪地球>", "target": "40.83亿", "type": "resolved" }, { "rela": "<avg_price>", "source": "<流浪地球>", "target": "46", "type": "resolved" }, { "rela": "<avg_people>", "source": "<流浪地球>", "target": "50", "type": "resolved" }, { "rela": "<begin_date>", "source": "<流浪地球>", "target": "2019.02.05", "type": "resolved" } ]; var nodes = {}; links.forEach(function(link) { link.source = nodes[link.source] || (nodes[link.source] = {name: link.source}); link.target = nodes[link.target] || (nodes[link.target] = {name: link.target}); }); var width = 1920, height = 1080; var force = d3.layout.force() .nodes(d3.values(nodes)) .links(links) .size([width, height]) .linkDistance(180) .charge(-1500) .on("tick", tick) .start(); var svg = d3.select("body").append("svg") .attr("width", width) .attr("height", height); var marker= svg.append("marker") .attr("id", "resolved") .attr("markerUnits","userSpaceOnUse") .attr("viewBox", "0 -5 10 10") .attr("refX",32) .attr("refY", -1) .attr("markerWidth", 12) .attr("markerHeight", 12) .attr("orient", "auto") .attr("stroke-width",2) .append("path") .attr("d", "M0,-5L10,0L0,5") .attr('fill','#000000'); var edges_line = svg.selectAll(".edgepath") .data(force.links()) .enter() .append("path") .attr({ 'd': function(d) {return 'M '+d.source.x+' '+d.source.y+' L '+ d.target.x +' '+d.target.y}, 'class':'edgepath', 'id':function(d,i) {return 'edgepath'+i;}}) .style("stroke",function(d){ var lineColor; lineColor="#B43232"; return lineColor; }) .style("pointer-events", "none") .style("stroke-width",0.5) .attr("marker-end", "url(#resolved)" ); var edges_text = svg.append("g").selectAll(".edgelabel") .data(force.links()) .enter() .append("text") .style("pointer-events", "none") .attr({ 'class':'edgelabel', 'id':function(d,i){return 'edgepath'+i;}, 'dx':80, 'dy':0 }); edges_text.append('textPath') .attr('xlink:href',function(d,i) {return '#edgepath'+i}) .style("pointer-events", "none") .text(function(d){return d.rela;}); var circle = svg.append("g").selectAll("circle") .data(force.nodes()) .enter().append("circle") .style("fill",function(node){ var color; var link=links[node.index]; color="#F9EBF9"; return color; }) .style('stroke',function(node){ var color; var link=links[node.index]; color="#A254A2"; return color; }) .attr("r", 28) .on("click",function(node) { edges_line.style("stroke-width",function(line){ console.log(line); if(line.source.name==node.name || line.target.name==node.name){ return 4; }else{ return 0.5; } }); }) .call(force.drag); var text = svg.append("g").selectAll("text") .data(force.nodes()) .enter() .append("text") .attr("dy", ".35em") .attr("text-anchor", "middle") .style('fill',function(node){ var color; var link=links[node.index]; color="#A254A2"; return color; }).attr('x',function(d){ var re_en = /[a-zA-Z]+/g; if(d.name.match(re_en)){ d3.select(this).append('tspan') .attr('x',0) .attr('y',2) .text(function(){return d.name;}); } else if(d.name.length<=4){ d3.select(this).append('tspan') .attr('x',0) .attr('y',2) .text(function(){return d.name;}); }else{ var top=d.name.substring(0,4); var bot=d.name.substring(4,d.name.length); d3.select(this).text(function(){return '';}); d3.select(this).append('tspan') .attr('x',0) .attr('y',-7) .text(function(){return top;}); d3.select(this).append('tspan') .attr('x',0) .attr('y',10) .text(function(){return bot;}); } }); function tick() { circle.attr("transform", transform1); text.attr("transform", transform2); edges_line.attr('d', function(d) { var path='M '+d.source.x+' '+d.source.y+' L '+ d.target.x +' '+d.target.y; return path; }); edges_text.attr('transform',function(d,i){ if (d.target.x<d.source.x){ bbox = this.getBBox(); rx = bbox.x+bbox.width/2; ry = bbox.y+bbox.height/2; return 'rotate(180 '+rx+' '+ry+')'; } else { return 'rotate(0)'; } }); } function linkArc(d) { return 'M '+d.source.x+' '+d.source.y+' L '+ d.target.x +' '+d.target.y } function transform1(d) { return "translate(" + d.x + "," + d.y + ")"; } function transform2(d) { return "translate(" + (d.x) + "," + d.y + ")"; } </script>
在浏览器中打开,效果如下:
这个绘图的效果会比Cayley自带的效果好一些,但功能还是有限。
总结
网上关于Cayley的相关资料比较少,基本只有官方文档和社区作为参考。本文所讲述的内容如有不足之处,还请读者多多指教~另外,关于Cayley的可视化,如读者有更好地办法实现,也欢迎告知笔者~
注意:不妨了解下笔者的微信公众号: Python爬虫与算法(微信号为:easy_web_scrape), 欢迎大家关注~