[Resources.AWS] Add host.image.id for EC2

src/OpenTelemetry.Resources.AWS/AWSEC2Detector.cs

@@ -72,6 +72,7 @@ internal List<KeyValuePair<string, object>> ExtractResourceAttributes(AWSEC2Iden
                 .AddAttributeCloudAccountID(identity?.AccountId)
                 .AddAttributeCloudAvailabilityZone(identity?.AvailabilityZone)
                 .AddAttributeHostID(identity?.InstanceId)
+                .AddAttributeHostImageId(identity?.ImageId)
                 .AddAttributeHostType(identity?.InstanceType)
                 .AddAttributeCloudRegion(identity?.Region)
                 .Build();

src/OpenTelemetry.Resources.AWS/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+* Added `host.image.id` resource attribute to `AWSEC2Detector`, populated from
+  the EC2 instance identity document's `imageId` (AMI ID).
+  ([#5110](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/5110))
+
 ## 1.18.0
 
 Released 2026-Aug-21

src/OpenTelemetry.Resources.AWS/Models/AWSEC2IdentityDocumentModel.cs

@@ -5,6 +5,8 @@
 
 namespace OpenTelemetry.Resources.AWS.Models;
 
+// See https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/instance-identity-documents.html
+
 internal class AWSEC2IdentityDocumentModel
 {
     [JsonPropertyName("accountId")]
@@ -21,4 +23,7 @@ internal class AWSEC2IdentityDocumentModel
 
     [JsonPropertyName("instanceType")]
     public string? InstanceType { get; set; }
+
+    [JsonPropertyName("imageId")]
+    public string? ImageId { get; set; }
 }

src/OpenTelemetry.Resources.AWS/README.md

@@ -54,7 +54,7 @@ The resource detectors will record the following metadata based on where
 your application is running:
 
 - **AWSEC2Detector**: cloud provider, cloud platform, account id,
-cloud availability zone, host id, host type, aws region, host name.
+cloud availability zone, host id, host type, host image id, aws region, host name.
 - **AWSEBSDetector**: cloud provider, cloud platform, service name,
 service namespace, instance id, service version.
 - **AWSECSDetector**: cloud provider, cloud platform, cloud resource id,

src/Shared/AWS/AWSSemanticConventions.Base.cs

@@ -544,6 +544,14 @@ private abstract class AWSSemanticConventionsBase
         /// </remarks>
         public virtual string AttributeHostType => string.Empty;
 
+        /// <summary>
+        /// VM image ID or host OS image ID. For Cloud, this value is from the provider.
+        /// </summary>
+        /// <remarks>
+        /// HostAttributes.AttributeHostImageId
+        /// </remarks>
+        public virtual string AttributeHostImageId => string.Empty;
+
         /// <summary>
         /// Name of the host. On Unix systems, it may contain what the hostname command returns, or the fully qualified hostname, or another name specified by the user.
         /// </summary>

src/Shared/AWS/AWSSemanticConventions.Legacy.cs

@@ -83,6 +83,7 @@ private abstract class AWSSemanticConventionsLegacy : AWSSemanticConventionsBase
         public override string AttributeHostID => "host.id";
         public override string AttributeHostType => "host.type";
         public override string AttributeHostName => "host.name";
+        public override string AttributeHostImageId => "host.image.id";
 
         // HTTP Attributes
         [Obsolete("Replaced by <c>http.response.status_code</c>.")]

src/Shared/AWS/AWSSemanticConventions.cs

@@ -341,6 +341,10 @@ public AttributeBuilderImpl AddAttributeHostType(object? value, bool addIfEmpty
         public AttributeBuilderImpl AddAttributeHostName(object? value, bool addIfEmpty = false) =>
             this.awsSemanticConventions.Add(this, x => x.AttributeHostName, value, addIfEmpty);
 
+        /// <inheritdoc cref="AWSSemanticConventionsBase.AttributeHostImageId"/>
+        public AttributeBuilderImpl AddAttributeHostImageId(object? value, bool addIfEmpty = false) =>
+            this.awsSemanticConventions.Add(this, x => x.AttributeHostImageId, value, addIfEmpty);
+
         #endregion
 
         #region Http

test/OpenTelemetry.Resources.AWS.Tests/AWSEC2DetectorTests.cs

@@ -87,6 +87,7 @@ public void TestExtractResourceAttributes(SemanticConventionVersion semanticConv
         Assert.Equal("Test availability zone", resourceAttributes[ExpectedSemanticConventions.AttributeCloudAvailabilityZone]);
         Assert.Equal("Test instance id", resourceAttributes[ExpectedSemanticConventions.AttributeHostID]);
         Assert.Equal("Test instance type", resourceAttributes[ExpectedSemanticConventions.AttributeHostType]);
+        Assert.Equal("Test image id", resourceAttributes[ExpectedSemanticConventions.AttributeHostImageId]);
         Assert.Equal("Test aws region", resourceAttributes[ExpectedSemanticConventions.AttributeCloudRegion]);
         Assert.Equal("Test host name", resourceAttributes[ExpectedSemanticConventions.AttributeHostName]);
     }
@@ -103,6 +104,7 @@ public void TestDeserializeResponse()
         Assert.Equal("us-east-1a", ec2IdentityDocumentModel.AvailabilityZone);
         Assert.Equal("i-12345678901234567", ec2IdentityDocumentModel.InstanceId);
         Assert.Equal("t2.micro", ec2IdentityDocumentModel.InstanceType);
+        Assert.Equal("ami-12345678901234567", ec2IdentityDocumentModel.ImageId);
         Assert.Equal("us-east-1", ec2IdentityDocumentModel.Region);
     }
 
@@ -114,6 +116,7 @@ private static class ExpectedSemanticConventions
         public const string AttributeCloudAvailabilityZone = "cloud.availability_zone";
         public const string AttributeCloudRegion = "cloud.region";
         public const string AttributeHostID = "host.id";
+        public const string AttributeHostImageId = "host.image.id";
         public const string AttributeHostType = "host.type";
         public const string AttributeHostName = "host.name";
     }

test/OpenTelemetry.Resources.AWS.Tests/SampleAWSEC2IdentityDocumentModel.cs

@@ -14,5 +14,6 @@ public SampleAWSEC2IdentityDocumentModel()
         this.Region = "Test aws region";
         this.InstanceId = "Test instance id";
         this.InstanceType = "Test instance type";
+        this.ImageId = "Test image id";
     }
 }