#数据模型

这篇文章是对我的  iris-globals-graphDB 应用的介绍。
在这篇文章中，我将演示如何在Python Flask Web 框架和PYVIS交互式网络可视化库的帮助下，将图形数据保存和抽取到InterSystems Globals中。

建议

• 阅读相关文档 使用 Globals
• 原生 SDK 介绍
• PYVIS 互动式网络可视化库

第一步 : 通过使用Python 原生SDK建立与IRIS Globals的链接

 #create and establish connection
  if not self.iris_connection:
         self.iris_connection = irisnative.createConnection("localhost", 1972, "USER", "superuser", "SYS")
                                     
  # Create an iris object
  self.iris_native = irisnative.createIris(self.iris_connection)
  return self.iris_native

第二步 : 使用 iris_native.set( ) 功能把数据保存到Globals 里     

#import nodes data from csv file
isdefined = self.iris_native.isDefined("^g1nodes")
if isdefined == 0:
    with open("/opt/irisapp/misc/g1nodes.csv", newline='') as csvfile:

 reader = csv.DictReader(csvfile)
 for row in reader:
    self.iris_native.set(row["name"], "^g1nodes", row["id"])

 #import edges data from csv file
 isdefined = self.iris_native.isDefined("^g1edges")
 if isdefined == 0:
    with open("/opt/irisapp/misc/g1edges.csv", newline='') as csvfile:
 reader = csv.DictReader(csvfile)
 counter = 0                
 for row in reader:
    counter = counter + 1
    #Save data to globals
    self.iris_native.set(row["source"]+'-'+row["target"], "^g1edges", counter)  

第三步: 使用iris_native.get() 功能把节点和边缘数据从Globals传递给PYVIS

 #Get nodes data for basic graph    
  def get_g1nodes(self):
        iris = self.get_iris_native()
        leverl1_subscript_iter = iris.iterator("^g1nodes")
        result = []
        # Iterate over all nodes forwards
        for level1_subscript, level1_value in leverl1_subscript_iter:
            #Get data from globals
            val = iris.get("^g1nodes",level1_subscript)
            element = {"id": level1_subscript, "label": val, "shape":"circle"}
            result.append(element)            
        return result

    #Get edges data for basic graph  
    def get_g1edges(self):
        iris = self.get_iris_native()
        leverl1_subscript_iter = iris.iterator("^g1edges")
        result = []
        # Iterate over all nodes forwards
        for level1_subscript, level1_value in leverl1_subscript_iter:
            #Get data from globals
            val = iris.get("^g1edges",level1_subscript)
            element = {"from": int(val.rpartition('-')[0]), "to": int(val.rpartition('-')[2])}
            result.append(element)            
        return result

Step4: Use PYVIS Javascript to generate graph data

<script type="text/javascript">
    // initialize global variables.
    var edges;
    var nodes;
    var network;
    var container;
    var options, data;
  
    // This method is responsible for drawing the graph, returns the drawn network
    function drawGraph() {
        var container = document.getElementById('mynetwork');
        let node = JSON.parse('{{ nodes | tojson }}');
        let edge = JSON.parse('{{ edges | tojson }}');
     
        // parsing and collecting nodes and edges from the python
        nodes = new vis.DataSet(node);
        edges = new vis.DataSet(edge);

        // adding nodes and edges to the graph
        data = {nodes: nodes, edges: edges};

        var options = {
            "configure": {
                "enabled": true,
                "filter": [
                "physics","nodes"
            ]
            },
            "nodes": {
                "color": {
                  "border": "rgba(233,180,56,1)",
                  "background": "rgba(252,175,41,1)",
                  "highlight": {
                    "border": "rgba(38,137,233,1)",
                    "background": "rgba(40,138,255,1)"
                  },
                  "hover": {
                    "border": "rgba(42,127,233,1)",
                    "background": "rgba(42,126,255,1)"
                 }
                },

                "font": {
                  "color": "rgba(255,255,255,1)"
                }
              },
            "edges": {
                "color": {
                    "inherit": true
                },
                "smooth": {
                    "enabled": false,
                    "type": "continuous"
                }
            },
            "interaction": {
                "dragNodes": true,
                "hideEdgesOnDrag": false,
                "hideNodesOnDrag": false,
                "navigationButtons": true,
                "hover": true
            },

            "physics": {
                "barnesHut": {
                    "avoidOverlap": 0,
                    "centralGravity": 0.3,
                    "damping": 0.09,
                    "gravitationalConstant": -80000,
                    "springConstant": 0.001,
                    "springLength": 250
                },

                "enabled": true,
                "stabilization": {
                    "enabled": true,
                    "fit": true,
                    "iterations": 1000,
                    "onlyDynamicEdges": false,
                    "updateInterval": 50
                }
            }
        }
        // if this network requires displaying the configure window,
        // put it in its div
        options.configure["container"] = document.getElementById("config");
        network = new vis.Network(container, data, options);
        return network;
    }
    drawGraph();
</script>

第五步: 从app.py 主文件调用上面的代码

#Mian route. (index)
@app.route("/")
def index():
    #Establish connection and import data to globals
    irisglobal = IRISGLOBAL()
    irisglobal.import_g1_nodes_edges()
    irisglobal.import_g2_nodes_edges()

    #getting nodes data from globals
    nodes = irisglobal.get_g1nodes()
    #getting edges data from globals
    edges = irisglobal.get_g1edges()

    #To display graph with configuration
    pyvis = True
    return render_template('index.html', nodes = nodes,edges=edges,pyvis=pyvis)    

下面是关于此项目的 介绍视频：