Include process information in metadata stanza when emiting events to…

… apm-server (#2272)

* Include process information in metadata stanza when emiting events to apm-server

* fix missing space

* ensure process is available on mock apm server too

* move ProcessInformation to API and implement a ToString()

* add max length validation to process.title

src/Elastic.Apm/Api/ProcessInformation.cs

@@ -0,0 +1,30 @@
+// Licensed to Elasticsearch B.V under
+// one or more agreements.
+// Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
+// See the LICENSE file in the project root for more information
+
+using System.Diagnostics;
+using Elastic.Apm.Api.Constraints;
+using Elastic.Apm.Helpers;
+
+namespace Elastic.Apm.Api;
+
+internal class ProcessInformation
+{
+	public int Pid { get; set; }
+
+	[MaxLength]
+	public string Title { get; set; }
+
+	public static ProcessInformation Create()
+	{
+		var p = Process.GetCurrentProcess();
+		return new ProcessInformation { Pid = p.Id, Title = p.ProcessName };
+	}
+
+	public override string ToString() => new ToStringBuilder(nameof(Service))
+	{
+		{ nameof(Pid), Pid },
+		{ nameof(Title), Title }
+	}.ToString();
+}

src/Elastic.Apm/Model/Metadata.cs

@@ -18,6 +18,8 @@ internal class Metadata
 		// ReSharper disable once UnusedAutoPropertyAccessor.Global - used by Json.Net
 		public Service Service { get; set; }
 
+		public ProcessInformation Process { get; set; }
+
 		// ReSharper disable once UnusedAutoPropertyAccessor.Global
 		public Api.System System { get; set; }
 

src/Elastic.Apm/Report/PayloadSenderV2.cs

@@ -88,7 +88,8 @@ public PayloadSenderV2(
 			_cloudMetadataProviderCollection = new CloudMetadataProviderCollection(configuration.CloudProvider, _logger, environmentVariables);
 			_apmServerInfo = apmServerInfo ?? new ApmServerInfo();
 			_serverInfoCallback = serverInfoCallback;
-			_metadata = new Metadata { Service = service, System = System };
+			var process = ProcessInformation.Create();
+			_metadata = new Metadata { Service = service, System = System, Process = process };
 			foreach (var globalLabelKeyValue in configuration.GlobalLabels)
 				_metadata.Labels.Add(globalLabelKeyValue.Key, globalLabelKeyValue.Value);
 			_cachedActivationMethod = _metadata.Service?.Agent.ActivationMethod;

test/Elastic.Apm.Tests.MockApmServer/MetadataDto.cs

@@ -6,6 +6,7 @@
 using Elastic.Apm.Api;
 using Elastic.Apm.Config;
 using Elastic.Apm.Helpers;
+using Elastic.Apm.Model;
 
 // ReSharper disable MemberCanBePrivate.Global
 // ReSharper disable UnusedAutoPropertyAccessor.Global
@@ -17,6 +18,7 @@ namespace Elastic.Apm.Tests.MockApmServer
 	internal class MetadataDto : IDto
 	{
 		public Service Service { get; set; }
+		public ProcessInformation Process { get; set; }
 		public Api.System System { get; set; }
 		public Api.Cloud Cloud { get; set; }
 		public Dictionary<string, string> Labels { get; set; }
@@ -25,6 +27,7 @@ public override string ToString() =>
 			new ToStringBuilder(nameof(MetadataDto))
 			{
 				{ nameof(Service), Service },
+				{ nameof(Process), Process },
 				{ nameof(System), System },
 				{ nameof(Labels), AbstractConfigurationReader.ToLogString(Labels) },
 				{ nameof(Cloud), Cloud },