Question:
I was using Titan 1.0 with gremlin server to create and delete a vertex. I want to implement this logic in my .net project. I wonder if there is any pre-build plugin for Titan and gremlin server in asp.net?
Currently, I'm directly using a command prompt to create and delete the required vertices and edges. how can I implement it in my .net MVC project?
Solution:
I've created one class in my project for interacting with Gremlin server using REST API. you can make small changes to make it work for you.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Web;
using Newtonsoft.Json;
using RestSharp;
using urNotice.Common.Infrastructure.Common.Config;
using urNotice.Common.Infrastructure.Common.Constants;
using urNotice.Common.Infrastructure.Common.Enum;
using urNotice.Common.Infrastructure.commonMethods;
using urNotice.Common.Infrastructure.Model.urNoticeModel.DynamoDb;
using urNotice.Services.NoSqlDb.DynamoDb;
namespace urNotice.Services.GraphDb
{
public class GremlinServerGraphEdgeDb : IGraphEdgeDb
{
private delegate Dictionary<string, string> AddEdgeAsyncDelegate(string userName, string graphName, Dictionary<string, string> properties);
public Dictionary<string, string> AddEdge(string userName, string graphName, Dictionary<string, string> properties)
{
string url = TitanGraphConfig.Server;
var response = CreateEdge(graphName, properties, url);
// add edge to dynamodb.
var edgeDetail = new OrbitPageEdgeDetail
{
url = url,
edgeId = response[TitanGraphConstants.Id],
graphName = graphName,
properties = properties
};
IDynamoDb dynamoDbModel = new DynamoDb();
dynamoDbModel.UpsertOrbitPageEdgeDetail(edgeDetail, userName, properties[EdgePropertyEnum._inV.ToString()], properties[EdgePropertyEnum._outV.ToString()]);
//Adding edgeDetail for faster query.
//dynamoDbModel.UpsertOrbitPageEdgeForQueryDetail(edgeDetail, userName, properties[EdgePropertyEnum._inV.ToString()], properties[EdgePropertyEnum._outV.ToString()]);
return response;
}
public Dictionary<string, string> DeleteEdge(string inV, string outV, string label)
{
string url = TitanGraphConfig.Server;
IDynamoDb dynamoDbModel = new DynamoDb();
string uniqueKey = OrbitPageUtil.GenerateUniqueKeyForEdgeQuery(inV, label, outV);
var edgeInfo = dynamoDbModel.GetOrbitPageCompanyUserWorkgraphyTable(
DynamoDbHashKeyDataType.EdgeDetail.ToString(),
uniqueKey,
null);
if (edgeInfo == null)
return null;
var response = DeleteEdgeNative(TitanGraphConfig.Graph, edgeInfo.CompareId, url);
dynamoDbModel.DeleteOrbitPageCompanyUserWorkgraphyTable(edgeInfo);
//Deleting Edge detail creating for only query purpose.
//string uniqueKey = OrbitPageUtil.GenerateUniqueKeyForEdgeQuery(inV, label, outV);
//edgeInfo = dynamoDbModel.GetOrbitPageCompanyUserWorkgraphyTable(
// DynamoDbHashKeyDataType.EdgeDetail.ToString(),
// uniqueKey,
// null);
//if(edgeInfo!=null)
// dynamoDbModel.DeleteOrbitPageCompanyUserWorkgraphyTable(edgeInfo);
return response;
}
public Dictionary<string, string> AddEdgeAsync(string userName, string graphName, Dictionary<string, string> properties)
{
var addEdgeAsyncDelegate = new GremlinServerGraphEdgeDb.AddEdgeAsyncDelegate(AddEdge);
addEdgeAsyncDelegate.BeginInvoke(userName, graphName, properties, null, null);
return null;
}
private Dictionary<String, String> CreateEdge(string graphName, Dictionary<string, string> properties, string url)
{
var uri = new StringBuilder(url + "/?gremlin=");
//http://localhost:8182/?gremlin=g.V(8320).next().addEdge("Using",g.V(12416).next(),"Desc","Item used by Person","time",12345)
string graphProperties = string.Empty;
//_outV must be the first parameter
graphProperties += "'" + properties[EdgePropertyEnum._label.ToString()] + "', g.V(" + properties[EdgePropertyEnum._inV.ToString()] + ").next() ,";
foreach (KeyValuePair<string, string> property in properties)
{
if (property.Key == EdgePropertyEnum._inV.ToString() || property.Key == EdgePropertyEnum._outV.ToString() || property.Key == EdgePropertyEnum._label.ToString())
{
//do nothing.. May be in future we will write logic here.
}
else
{
if (property.Key == EdgePropertyEnum.PostedDateLong.ToString() || property.Key == EdgePropertyEnum.SalaryAmount.ToString())
graphProperties += "'" + property.Key + "', " + property.Value + " ,";
else
graphProperties += "'" + property.Key + "', '" + property.Value + "' ,";
}
}
if (!string.IsNullOrEmpty(graphProperties))
{
graphProperties = graphProperties.Substring(0, graphProperties.Length - 2);
}
uri.Append("g.V(" + properties[EdgePropertyEnum._outV.ToString()] + ").next().addEdge(" + graphProperties + ");");
var client = new RestClient(uri.ToString());
var request = new RestRequest();
request.Method = Method.GET;
request.AddHeader("Accept", "application/json");
request.Parameters.Clear();
request.AddParameter("application/json", "", ParameterType.RequestBody);
var res = client.Execute(request);
var content = res.Content; // raw content as string
dynamic jsonResponse = JsonConvert.DeserializeObject(content);
var response = new Dictionary<String, String>();
response["status"] = "200";
response["CreateEdgeStatus"] = "200";
response[TitanGraphConstants.Id] = jsonResponse.result.data[0].id;
response[TitanGraphConstants.RexsterUri] = url;
return response;
}
private Dictionary<String, String> DeleteEdgeNative(string graphName, string edgeId, string url)
{
var uri = new StringBuilder(url + "/?gremlin=");
//var uri = new StringBuilder(url + "/graphs/" + graphName + "/edges/" + edgeId);
//http://localhost:8182/?gremlin=g.E('odxqo-6f4-2hat-9kw').drop()
uri.Append("g.E('" + edgeId + "').drop();");
var client = new RestClient(uri.ToString());
var request = new RestRequest();
request.Method = Method.GET;
request.AddHeader("Accept", "application/json");
request.Parameters.Clear();
request.AddParameter("application/json", "", ParameterType.RequestBody);
var res = client.Execute(request);
var content = res.Content; // raw content as string
dynamic jsonResponse = JsonConvert.DeserializeObject(content);
var response = new Dictionary<String, String>();
response["status"] = "200";
response["DeleteEdgeStatus"] = "200";
//response[TitanGraphConstants.Id] = jsonResponse.result.data[0].id;
//response[TitanGraphConstants.RexsterUri] = url;
return response;
}
}
}
