[Resources.Container] Add Kubernetes support

opentelemetry-dotnet-contrib.sln

@@ -238,6 +238,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Shared", "Shared", "{1FCC8E
 	ProjectSection(SolutionItems) = preProject
 		src\Shared\ActivityInstrumentationHelper.cs = src\Shared\ActivityInstrumentationHelper.cs
 		src\Shared\AssemblyVersionExtensions.cs = src\Shared\AssemblyVersionExtensions.cs
+		src\Shared\AsyncHelper.cs = src\Shared\AsyncHelper.cs
 		src\Shared\DiagnosticSourceListener.cs = src\Shared\DiagnosticSourceListener.cs
 		src\Shared\DiagnosticSourceSubscriber.cs = src\Shared\DiagnosticSourceSubscriber.cs
 		src\Shared\ExceptionExtensions.cs = src\Shared\ExceptionExtensions.cs
@@ -252,6 +253,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Shared", "Shared", "{1FCC8E
 		src\Shared\PropertyFetcher.AOT.cs = src\Shared\PropertyFetcher.AOT.cs
 		src\Shared\PropertyFetcher.cs = src\Shared\PropertyFetcher.cs
 		src\Shared\RedactionHelper.cs = src\Shared\RedactionHelper.cs
+		src\Shared\ResourceDetectorUtils.cs = src\Shared\ResourceDetectorUtils.cs
 		src\Shared\ResourceSemanticConventions.cs = src\Shared\ResourceSemanticConventions.cs
 		src\Shared\SemanticConventions.cs = src\Shared\SemanticConventions.cs
 		src\Shared\ServerCertificateValidationHandler.cs = src\Shared\ServerCertificateValidationHandler.cs

src/OpenTelemetry.Resources.AWS/AWSEKSDetector.cs

@@ -62,7 +62,7 @@ internal static List<KeyValuePair<string, object>> ExtractResourceAttributes(str
     {
         try
         {
-            var stringBuilder = new StringBuilder();
+            var stringBuilder = new StringBuilder("Bearer ");
 
             using (var streamReader = ResourceDetectorUtils.GetStreamReader(path))
             {
@@ -72,8 +72,6 @@ internal static List<KeyValuePair<string, object>> ExtractResourceAttributes(str
                 }
             }
 
-            stringBuilder.Insert(0, "Bearer ");
-
             return stringBuilder.ToString();
         }
         catch (Exception ex)

src/OpenTelemetry.Resources.AWS/OpenTelemetry.Resources.AWS.csproj

@@ -27,9 +27,11 @@
   </ItemGroup>
 
   <ItemGroup>
+    <Compile Include="$(RepoRoot)\src\Shared\AsyncHelper.cs" Link="Includes\AsyncHelper.cs" />
     <Compile Include="$(RepoRoot)\src\Shared\ExceptionExtensions.cs" Link="Includes\ExceptionExtensions.cs" />
     <Compile Include="$(RepoRoot)\src\Shared\Guard.cs" Link="Includes\Guard.cs" />
     <Compile Include="$(RepoRoot)\src\Shared\IServerCertificateValidationEventSource.cs" Link="Includes\IServerCertificateValidationEventSource.cs" />
+    <Compile Include="$(RepoRoot)\src\Shared\ResourceDetectorUtils.cs" Link="Includes\ResourceDetectorUtils.cs" />
     <Compile Include="$(RepoRoot)\src\Shared\ServerCertificateValidationHandler.cs" Link="Includes\ServerCertificateValidationHandler.cs" />
     <Compile Include="$(RepoRoot)\src\Shared\ServerCertificateValidationProvider.cs" Link="Includes\ServerCertificateValidationProvider.cs" />
   </ItemGroup>

src/OpenTelemetry.Resources.Container/CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+* Add Kubernetes support.
+  ([#1699](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/1699))
+
 ## 1.0.0-beta.9
 
 Released 2024-Jun-18

src/OpenTelemetry.Resources.Container/ContainerDetector.cs

@@ -14,21 +14,25 @@ internal sealed class ContainerDetector : IResourceDetector
     private const string Filepath = "/proc/self/cgroup";
     private const string FilepathV2 = "/proc/self/mountinfo";
     private const string Hostname = "hostname";
+    private const string K8sCertificatePath = "/var/run/secrets/kubernetes.io/serviceaccount/ca.crt";
+
+    private readonly IK8sMetadataFetcher k8sMetadataFetcher;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="ContainerDetector"/> class.
+    /// </summary>
+    public ContainerDetector()
+        : this(new K8sMetadataFetcher())
+    {
+    }
 
     /// <summary>
-    /// CGroup Parse Versions.
+    /// Initializes a new instance of the <see cref="ContainerDetector"/> class for testing.
     /// </summary>
-    internal enum ParseMode
+    /// <param name="k8sMetadataFetcher">The <see cref="IK8sMetadataFetcher"/>.</param>
+    internal ContainerDetector(IK8sMetadataFetcher k8sMetadataFetcher)
     {
-        /// <summary>
-        /// Represents CGroupV1.
-        /// </summary>
-        V1,
-
-        /// <summary>
-        /// Represents CGroupV2.
-        /// </summary>
-        V2,
+        this.k8sMetadataFetcher = k8sMetadataFetcher;
     }
 
     /// <summary>
@@ -37,33 +41,74 @@ internal enum ParseMode
     /// <returns>Resource with key-value pairs of resource attributes.</returns>
     public Resource Detect()
     {
-        var cGroupBuild = this.BuildResource(Filepath, ParseMode.V1);
-        if (cGroupBuild == Resource.Empty)
+        var containerId = this.ExtractK8sContainerId();
+        if (!string.IsNullOrEmpty(containerId))
+        {
+            return BuildResource(containerId);
+        }
+
+        containerId = this.ExtractContainerId(Filepath, ParseMode.V1);
+        if (!string.IsNullOrEmpty(containerId))
+        {
+            return BuildResource(containerId);
+        }
+
+        containerId = this.ExtractContainerId(FilepathV2, ParseMode.V2);
+        if (!string.IsNullOrEmpty(containerId))
         {
-            cGroupBuild = this.BuildResource(FilepathV2, ParseMode.V2);
+            return BuildResource(containerId);
         }
 
-        return cGroupBuild;
+        return Resource.Empty;
+
+        static Resource BuildResource(string containerId)
+        {
+            return new Resource(new List<KeyValuePair<string, object>>(1) { new(ContainerSemanticConventions.AttributeContainerId, containerId!) });
+        }
     }
 
     /// <summary>
-    /// Builds the resource attributes from Container Id in file path.
+    /// Extracts Container Id from path using the cgroupv1 format.
     /// </summary>
-    /// <param name="path">File path where container id exists.</param>
-    /// <param name="cgroupVersion">CGroup Version of file to parse from.</param>
-    /// <returns>Returns Resource with list of key-value pairs of container resource attributes if container id exists else empty resource.</returns>
-    internal Resource BuildResource(string path, ParseMode cgroupVersion)
+    /// <param name="path">cgroup path.</param>
+    /// <param name="parseMode">CGroup Version of file to parse from.</param>
+    /// <returns>Container Id, <see langword="null" /> if not found or exception being thrown.</returns>
+    internal string? ExtractContainerId(string path, ParseMode parseMode)
     {
-        var containerId = this.ExtractContainerId(path, cgroupVersion);
-
-        if (string.IsNullOrEmpty(containerId))
+        try
         {
-            return Resource.Empty;
+            if (!File.Exists(path))
+            {
+                return null;
+            }
+
+            foreach (string line in File.ReadLines(path))
+            {
+                string? containerId = null;
+                if (!string.IsNullOrEmpty(line))
+                {
+                    if (parseMode == ParseMode.V1)
+                    {
+                        containerId = GetIdFromLineV1(line);
+                    }
+                    else if (parseMode == ParseMode.V2 && line.Contains(Hostname, StringComparison.Ordinal))
+                    {
+                        containerId = GetIdFromLineV2(line);
+                    }
+                }
+
+                if (!string.IsNullOrEmpty(containerId))
+                {
+                    return containerId;
+                }
+            }
         }
-        else
+        catch (Exception ex)
         {
-            return new Resource(new List<KeyValuePair<string, object>>(1) { new(ContainerSemanticConventions.AttributeContainerId, containerId!) });
+            ContainerResourceEventSource.Log.ExtractResourceAttributesException($"{nameof(ContainerDetector)} : Failed to extract Container id from path", ex);
         }
+
+        return null;
     }
 
     /// <summary>
@@ -119,7 +164,6 @@ internal Resource BuildResource(string path, ParseMode cgroupVersion)
     private static string RemovePrefixAndSuffixIfNeeded(string input, int startIndex, int endIndex)
     {
         startIndex = (startIndex == -1) ? 0 : startIndex + 1;
-
         if (endIndex == -1)
         {
             endIndex = input.Length;
@@ -128,45 +172,47 @@ private static string RemovePrefixAndSuffixIfNeeded(string input, int startIndex
         return input.Substring(startIndex, endIndex - startIndex);
     }
 
-    /// <summary>
-    /// Extracts Container Id from path using the cgroupv1 format.
-    /// </summary>
-    /// <param name="path">cgroup path.</param>
-    /// <param name="cgroupVersion">CGroup Version of file to parse from.</param>
-    /// <returns>Container Id, Null if not found or exception being thrown.</returns>
-    private string? ExtractContainerId(string path, ParseMode cgroupVersion)
+    private string? ExtractK8sContainerId()
     {
         try
         {
-            if (!File.Exists(path))
+            var baseUrl = this.k8sMetadataFetcher.GetServiceBaseUrl();
+            var containerName = this.k8sMetadataFetcher.GetContainerName();
+            if (string.IsNullOrEmpty(baseUrl) || string.IsNullOrEmpty(containerName))
             {
                 return null;
             }
 
-            foreach (string line in File.ReadLines(path))
+            var @namespace = this.k8sMetadataFetcher.GetNamespace();
+            var hostname = this.k8sMetadataFetcher.GetPodName() ?? this.k8sMetadataFetcher.GetHostname();
+            var url = $"{baseUrl}/api/v1/namespaces/{@namespace}/pods/{hostname}";
+            var credentials = this.k8sMetadataFetcher.GetApiCredential();
+            if (string.IsNullOrEmpty(credentials))
             {
-                string? containerId = null;
-                if (!string.IsNullOrEmpty(line))
-                {
-                    if (cgroupVersion == ParseMode.V1)
-                    {
-                        containerId = GetIdFromLineV1(line);
-                    }
-                    else if (cgroupVersion == ParseMode.V2 && line.Contains(Hostname, StringComparison.Ordinal))
-                    {
-                        containerId = GetIdFromLineV2(line);
-                    }
-                }
+                return null;
+            }
 
-                if (!string.IsNullOrEmpty(containerId))
-                {
-                    return containerId;
-                }
+            using var httpClientHandler = ServerCertificateValidationHandler.Create(K8sCertificatePath, ContainerResourceEventSource.Log);
+            var response = AsyncHelper.RunSync(() => ResourceDetectorUtils.SendOutRequestAsync(url, HttpMethod.Get, new KeyValuePair<string, string>("Authorization", credentials), httpClientHandler));
+            var pod = ResourceDetectorUtils.DeserializeFromString(response, SourceGenerationContext.Default.K8sPod);
+            if (pod?.Status?.ContainerStatuses == null)
+            {
+                return null;
             }
+
+            var container = pod.Status.ContainerStatuses.SingleOrDefault(p => p.Name == containerName);
+            if (string.IsNullOrEmpty(container?.Id))
+            {
+                return null;
+            }
+
+            // Container's ID is in <type>://<container_id> format.
+            var index = container.Id.LastIndexOf('/');
+            return container.Id.Substring(index + 1);
         }
         catch (Exception ex)
         {
-            ContainerExtensionsEventSource.Log.ExtractResourceAttributesException($"{nameof(ContainerDetector)} : Failed to extract Container id from path", ex);
+            ContainerResourceEventSource.Log.ExtractResourceAttributesException($"{nameof(ContainerDetector)}: Failed to extract container id", ex);
         }
 
         return null;

src/OpenTelemetry.Resources.Container/ContainerResourceEventSource.cs

@@ -0,0 +1,58 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+using System.Diagnostics.Tracing;
+using OpenTelemetry.Internal;
+
+namespace OpenTelemetry.Resources.Container;
+
+[EventSource(Name = "OpenTelemetry-Resources-Container")]
+internal class ContainerResourceEventSource : EventSource, IServerCertificateValidationEventSource
+{
+    public static ContainerResourceEventSource Log = new();
+
+    private const int EventIdFailedToExtractResourceAttributes = 1;
+    private const int EventIdFailedToValidateCertificate = 2;
+    private const int EventIdFailedToCreateHttpHandler = 3;
+    private const int EventIdFailedCertificateFileNotExists = 4;
+    private const int EventIdFailedToLoadCertificateInStorage = 5;
+
+    [NonEvent]
+    public void ExtractResourceAttributesException(string format, Exception ex)
+    {
+        if (this.IsEnabled(EventLevel.Error, (EventKeywords)(-1)))
+        {
+            this.FailedToExtractResourceAttributes(format, ex.ToInvariantString());
+        }
+    }
+
+    [Event(EventIdFailedToExtractResourceAttributes, Message = "Failed to extract resource attributes in '{0}'.", Level = EventLevel.Error)]
+    public void FailedToExtractResourceAttributes(string format, string exception)
+    {
+        this.WriteEvent(EventIdFailedToExtractResourceAttributes, format, exception);
+    }
+
+    [Event(EventIdFailedToValidateCertificate, Message = "Failed to validate certificate. Details: '{0}'", Level = EventLevel.Warning)]
+    public void FailedToValidateCertificate(string error)
+    {
+        this.WriteEvent(EventIdFailedToValidateCertificate, error);
+    }
+
+    [Event(EventIdFailedToCreateHttpHandler, Message = "Failed to create HTTP handler. Exception: '{0}'", Level = EventLevel.Warning)]
+    public void FailedToCreateHttpHandler(Exception exception)
+    {
+        this.WriteEvent(EventIdFailedToCreateHttpHandler, exception.ToInvariantString());
+    }
+
+    [Event(EventIdFailedCertificateFileNotExists, Message = "Certificate file does not exist. File: '{0}'", Level = EventLevel.Warning)]
+    public void CertificateFileDoesNotExist(string filename)
+    {
+        this.WriteEvent(EventIdFailedCertificateFileNotExists, filename);
+    }
+
+    [Event(EventIdFailedToLoadCertificateInStorage, Message = "Failed to load certificate in trusted storage. File: '{0}'", Level = EventLevel.Warning)]
+    public void FailedToLoadCertificateInTrustedStorage(string filename)
+    {
+        this.WriteEvent(EventIdFailedToLoadCertificateInStorage, filename);
+    }
+}

src/OpenTelemetry.Resources.Container/IK8sMetadataFetcher.cs

@@ -0,0 +1,19 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+namespace OpenTelemetry.Resources.Container;
+
+internal interface IK8sMetadataFetcher
+{
+    string? GetApiCredential();
+
+    string? GetContainerName();
+
+    string? GetHostname();
+
+    string? GetPodName();
+
+    string? GetNamespace();
+
+    string? GetServiceBaseUrl();
+}