Pipes objects to Seq

WriteSeq.cs

// How to debug your powershell scripts by piping the intermediate results to Seq
// 1. Compile this into WriteSeq.dll
// 2. > Import-Module .\WriteSeq.dll
// 3. > Get-ChildItems C:\ | ? { $_.Name -ilike { "*Program*" } | Write-Seq | Format-Table 

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Management.Automation;
using System.Net;
using System.Reflection;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Json;
using System.Text;
using System.Threading;

namespace WriteSeq
{
    [Cmdlet("Write", "Seq",ConfirmImpact = ConfirmImpact.Low)]    
    public class WriteSeq : PSCmdlet
    {
        private string _seqUrl = "http://localhost:5341";
        private readonly List<Event> _events = new List<Event>();
            
        [Parameter(ValueFromPipeline = true, DontShow = true)]
        public PSObject[] InputObject { get; set; }

        [Parameter(Mandatory = false)]
        public string ApiKey { get; set; }

        [Parameter(Mandatory = false, HelpMessage = "The url of the Seq server. By default it is http://localhost:5341")]
        public string SeqUrl
        {
            get { return _seqUrl; }
            set { _seqUrl = value.TrimEnd('/'); }
        }

        protected override void ProcessRecord()
        {
            foreach (var o in InputObject)
            {
                _events.Add(ToEvent(o));
                WriteObject(o);
            }
            
        }

        protected override void EndProcessing()
        {
            PostRawEvents(_events);
        }

        private Event ToEvent(PSObject o)
        {
            return new Event()
            {
                MessageTemplate = o.ToString(),
                Level = "Information",
                Properties = o.Properties
                    .ToDictionary(p => p.Name, p => (object) p.Value.ToString()) 
            };
        }

        private void PostRawEvents(IEnumerable<Event> e)
        {
            var events = new RawEvents()
            {
                Events = e.ToArray()
            };

            using (var stream = new MemoryStream())
            {
                // .NET 4
                //new DataContractJsonSerializer(typeof(RawEvents)).WriteObject(stream, events);

                // .NET 45
                new DataContractJsonSerializer(typeof(RawEvents), new DataContractJsonSerializerSettings { UseSimpleDictionaryFormat = true}).WriteObject(stream, events);
                var buffer = stream.GetBuffer();
                
                WriteDebug(Encoding.UTF8.GetString(buffer));

                var requestUriString = SeqUrl + "/api/events/raw";
                if (!string.IsNullOrWhiteSpace(ApiKey))
                {
                    requestUriString += "?apiKey=" + ApiKey;
                }
                
                var request = (HttpWebRequest) WebRequest.Create(requestUriString);
                request.ContentType = "application/json";
                request.Method = WebRequestMethods.Http.Post;
                request.ContentLength = buffer.Length;
                request.KeepAlive = false;
                request.Timeout = Timeout.Infinite;
                request.ProtocolVersion = HttpVersion.Version10;

                using (var requestStream = request.GetRequestStream())
                {
                    requestStream.Write(buffer, 0, buffer.Length);
                }

                var response = request.GetResponse();
                using (var responseStream = response.GetResponseStream())
                {
                    new StreamReader(responseStream).ReadToEnd();
                }

            };

        }
    }

    [DataContract]
    internal class RawEvents
    {
        [DataMember]
        public Event[] Events { get; set; }
    }

    [DataContract]
    internal class Event
    {
        [DataMember]
        public string Timestamp
        {
            get { return DateTimeOffset.Now.ToString("yyyy-MM-ddThh:mm:ss.fff%K"); }
            set { }
        }

        [DataMember]
        public string Level { get; set; }

        [DataMember]
        public string MessageTemplate { get; set; }

        [DataMember]
        public IDictionary<string, object> Properties { get; set; }
    }
}