GroupGraph.cs

using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using SkiaSharp;
using Waher.Networking.XMPP;
using Waher.Script;
 
namespace Waher.Service.IoTBroker.Admin.Topology
{
    public class GroupGraph : CommandRegEx
    {
        public GroupGraph()
            : base(@"^groupgraph\s*.*$")
        {
        }
 
        public override string Name => "GroupGraph";
 
        public override async Task Execute(ChatState State, string[] Arguments, string OrgMessage, Match Details,
            ResponseCallbackHandler ResponseCallback)
        {
            string Script = OrgMessage.Substring(10).Trim();
            object Result;
            SKColor Color;
 
            if (string.IsNullOrEmpty(Script))
            {
                Result = null;
                Color = SKColors.Empty;
            }
            else
            {
                Expression Exp = new Expression(Script);
                Result = await Exp.EvaluateAsync(State.Session);
                Result = TopologyQuery.Simplify(Result, out Color);
            }
 
            StringBuilder sb = new StringBuilder();
            string Title = IoTGateway.Gateway.XmppClient.BareJID;
 
            sb.AppendLine("```dot");
            sb.AppendLine("digraph G {");
            sb.AppendLine("rankdir=LR");
 
            TopologyQuery.EmbedResult(sb, Title, Result, Color);
 
            foreach (RosterItem Item in IoTGateway.Gateway.XmppClient.Roster)
            {
                foreach (string Group in Item.Groups)
                {
                    sb.Append('"');
                    sb.Append(Title);
                    sb.Append("\" -> \"");
                    sb.Append(Item.BareJid);
                    sb.Append("\" [label=\"");
                    sb.Append(Group);
                    sb.AppendLine("\"];");
                }
            }
 
            sb.AppendLine("}");
            sb.AppendLine("```");
 
            await ResponseCallback(sb.ToString(), string.Empty);
        }
 
        public override HelpItem[] GetHelp()
        {
            return new HelpItem[]
            {
                new HelpItem("GroupGraph[ SCRIPT]", "Returns a GraphViz graph of the current broker and how it is connected to roster items with groups. Such a graph illustrates information flow authorized by group membership. Optional script can be provided, and its result embedded in the graph. Consolidating responses from multiple brokers generates a groups graph of all brokers.")
            };
        }
    }
}