Implement error.type attribute in HTTP semconv

instrumentation-api-semconv/src/main/java/io/opentelemetry/instrumentation/api/instrumenter/http/HttpClientAttributesExtractor.java

@@ -90,6 +90,7 @@ public static <REQUEST, RESPONSE> HttpClientAttributesExtractorBuilder<REQUEST,
   HttpClientAttributesExtractor(HttpClientAttributesExtractorBuilder<REQUEST, RESPONSE> builder) {
     super(
         builder.httpAttributesGetter,
+        HttpStatusCodeConverter.CLIENT,
         builder.capturedRequestHeaders,
         builder.capturedResponseHeaders,
         builder.knownMethods);

instrumentation-api-semconv/src/main/java/io/opentelemetry/instrumentation/api/instrumenter/http/HttpCommonAttributesExtractor.java

@@ -14,6 +14,7 @@
 import io.opentelemetry.api.common.AttributesBuilder;
 import io.opentelemetry.context.Context;
 import io.opentelemetry.instrumentation.api.instrumenter.AttributesExtractor;
+import io.opentelemetry.instrumentation.api.instrumenter.http.internal.HttpAttributes;
 import io.opentelemetry.instrumentation.api.internal.SemconvStability;
 import io.opentelemetry.semconv.SemanticAttributes;
 import java.util.HashSet;
@@ -31,16 +32,19 @@ abstract class HttpCommonAttributesExtractor<
     implements AttributesExtractor<REQUEST, RESPONSE> {
 
   final GETTER getter;
+  private final HttpStatusCodeConverter statusCodeConverter;
   private final List<String> capturedRequestHeaders;
   private final List<String> capturedResponseHeaders;
   private final Set<String> knownMethods;
 
   HttpCommonAttributesExtractor(
       GETTER getter,
+      HttpStatusCodeConverter statusCodeConverter,
       List<String> capturedRequestHeaders,
       List<String> capturedResponseHeaders,
       Set<String> knownMethods) {
     this.getter = getter;
+    this.statusCodeConverter = statusCodeConverter;
     this.capturedRequestHeaders = lowercase(capturedRequestHeaders);
     this.capturedResponseHeaders = lowercase(capturedResponseHeaders);
     this.knownMethods = new HashSet<>(knownMethods);
@@ -88,8 +92,9 @@ public void onEnd(
       internalSet(attributes, SemanticAttributes.HTTP_REQUEST_CONTENT_LENGTH, requestBodySize);
     }
 
+    Integer statusCode = null;
     if (response != null) {
-      Integer statusCode = getter.getHttpResponseStatusCode(request, response, error);
+      statusCode = getter.getHttpResponseStatusCode(request, response, error);
       if (statusCode != null && statusCode > 0) {
         if (SemconvStability.emitStableHttpSemconv()) {
           internalSet(attributes, SemanticAttributes.HTTP_RESPONSE_STATUS_CODE, (long) statusCode);
@@ -114,6 +119,25 @@ public void onEnd(
         }
       }
     }
+
+    if (SemconvStability.emitStableHttpSemconv()) {
+      String errorType = null;
+      if (statusCode != null && statusCode > 0) {
+        if (statusCodeConverter.isError(statusCode)) {
+          errorType = statusCode.toString();
+        }
+      } else {
+        errorType = getter.getErrorType(request, response, error);
+        // fall back to exception class name & _OTHER
+        if (errorType == null && error != null) {
+          errorType = error.getClass().getName();
+        }
+        if (errorType == null) {
+          errorType = _OTHER;
+        }
+      }
+      internalSet(attributes, HttpAttributes.ERROR_TYPE, errorType);
+    }
   }
 
   @Nullable

instrumentation-api-semconv/src/main/java/io/opentelemetry/instrumentation/api/instrumenter/http/HttpCommonAttributesGetter.java

@@ -53,4 +53,25 @@ public interface HttpCommonAttributesGetter<REQUEST, RESPONSE> {
    * returned instead.
    */
   List<String> getHttpResponseHeader(REQUEST request, RESPONSE response, String name);
+
+  /**
+   * Returns a description of a class of error the operation ended with.
+   *
+   * <p>This method is only called if the request failed before response status code was sent or
+   * received.
+   *
+   * <p>If this method is not implemented, or if it returns {@code null}, the exception class name
+   * (if any was caught) or the value {@code _OTHER} will be used as error type.
+   *
+   * <p>The cardinality of the error type should be low. The instrumentations implementing this
+   * method are recommended to document the custom values they support.
+   *
+   * <p>Examples: {@code Bad Request}, {@code java.net.UnknownHostException}, {@code request
+   * cancelled}, {@code _OTHER}.
+   */
+  @Nullable
+  default String getErrorType(
+      REQUEST request, @Nullable RESPONSE response, @Nullable Throwable throwable) {
+    return null;
+  }
 }

instrumentation-api-semconv/src/main/java/io/opentelemetry/instrumentation/api/instrumenter/http/HttpMetricsAdvice.java

@@ -13,6 +13,7 @@
 import io.opentelemetry.extension.incubator.metrics.ExtendedDoubleHistogramBuilder;
 import io.opentelemetry.extension.incubator.metrics.ExtendedLongHistogramBuilder;
 import io.opentelemetry.extension.incubator.metrics.ExtendedLongUpDownCounterBuilder;
+import io.opentelemetry.instrumentation.api.instrumenter.http.internal.HttpAttributes;
 import io.opentelemetry.semconv.SemanticAttributes;
 
 final class HttpMetricsAdvice {
@@ -26,6 +27,7 @@ static void applyStableClientDurationAdvice(DoubleHistogramBuilder builder) {
             asList(
                 SemanticAttributes.HTTP_REQUEST_METHOD,
                 SemanticAttributes.HTTP_RESPONSE_STATUS_CODE,
+                HttpAttributes.ERROR_TYPE,
                 SemanticAttributes.NETWORK_PROTOCOL_NAME,
                 SemanticAttributes.NETWORK_PROTOCOL_VERSION,
                 SemanticAttributes.SERVER_ADDRESS,
@@ -60,6 +62,7 @@ static void applyClientRequestSizeAdvice(LongHistogramBuilder builder) {
                 // stable attributes
                 SemanticAttributes.HTTP_REQUEST_METHOD,
                 SemanticAttributes.HTTP_RESPONSE_STATUS_CODE,
+                HttpAttributes.ERROR_TYPE,
                 SemanticAttributes.NETWORK_PROTOCOL_NAME,
                 SemanticAttributes.NETWORK_PROTOCOL_VERSION,
                 SemanticAttributes.SERVER_ADDRESS,
@@ -84,6 +87,7 @@ static void applyStableServerDurationAdvice(DoubleHistogramBuilder builder) {
                 SemanticAttributes.HTTP_ROUTE,
                 SemanticAttributes.HTTP_REQUEST_METHOD,
                 SemanticAttributes.HTTP_RESPONSE_STATUS_CODE,
+                HttpAttributes.ERROR_TYPE,
                 SemanticAttributes.NETWORK_PROTOCOL_NAME,
                 SemanticAttributes.NETWORK_PROTOCOL_VERSION,
                 SemanticAttributes.URL_SCHEME));
@@ -119,6 +123,7 @@ static void applyServerRequestSizeAdvice(LongHistogramBuilder builder) {
                 SemanticAttributes.HTTP_ROUTE,
                 SemanticAttributes.HTTP_REQUEST_METHOD,
                 SemanticAttributes.HTTP_RESPONSE_STATUS_CODE,
+                HttpAttributes.ERROR_TYPE,
                 SemanticAttributes.NETWORK_PROTOCOL_NAME,
                 SemanticAttributes.NETWORK_PROTOCOL_VERSION,
                 SemanticAttributes.URL_SCHEME,

instrumentation-api-semconv/src/main/java/io/opentelemetry/instrumentation/api/instrumenter/http/HttpServerAttributesExtractor.java

@@ -93,6 +93,7 @@ public static <REQUEST, RESPONSE> HttpServerAttributesExtractorBuilder<REQUEST,
   HttpServerAttributesExtractor(HttpServerAttributesExtractorBuilder<REQUEST, RESPONSE> builder) {
     super(
         builder.httpAttributesGetter,
+        HttpStatusCodeConverter.SERVER,
         builder.capturedRequestHeaders,
         builder.capturedResponseHeaders,
         builder.knownMethods);

instrumentation-api-semconv/src/main/java/io/opentelemetry/instrumentation/api/instrumenter/http/HttpSpanStatusExtractor.java

@@ -26,7 +26,7 @@ public final class HttpSpanStatusExtractor<REQUEST, RESPONSE>
    */
   public static <REQUEST, RESPONSE> SpanStatusExtractor<REQUEST, RESPONSE> create(
       HttpClientAttributesGetter<? super REQUEST, ? super RESPONSE> getter) {
-    return new HttpSpanStatusExtractor<>(getter, HttpStatusConverter.CLIENT);
+    return new HttpSpanStatusExtractor<>(getter, HttpStatusCodeConverter.CLIENT);
   }
 
   /**
@@ -36,17 +36,17 @@ public static <REQUEST, RESPONSE> SpanStatusExtractor<REQUEST, RESPONSE> create(
    */
   public static <REQUEST, RESPONSE> SpanStatusExtractor<REQUEST, RESPONSE> create(
       HttpServerAttributesGetter<? super REQUEST, ? super RESPONSE> getter) {
-    return new HttpSpanStatusExtractor<>(getter, HttpStatusConverter.SERVER);
+    return new HttpSpanStatusExtractor<>(getter, HttpStatusCodeConverter.SERVER);
   }
 
   private final HttpCommonAttributesGetter<? super REQUEST, ? super RESPONSE> getter;
-  private final HttpStatusConverter statusConverter;
+  private final HttpStatusCodeConverter statusCodeConverter;
 
   private HttpSpanStatusExtractor(
       HttpCommonAttributesGetter<? super REQUEST, ? super RESPONSE> getter,
-      HttpStatusConverter statusConverter) {
+      HttpStatusCodeConverter statusCodeConverter) {
     this.getter = getter;
-    this.statusConverter = statusConverter;
+    this.statusCodeConverter = statusCodeConverter;
   }
 
   @Override
@@ -59,9 +59,8 @@ public void extract(
     if (response != null) {
       Integer statusCode = getter.getHttpResponseStatusCode(request, response, error);
       if (statusCode != null) {
-        StatusCode statusCodeObj = statusConverter.statusFromHttpStatus(statusCode);
-        if (statusCodeObj == StatusCode.ERROR) {
-          spanStatusBuilder.setStatus(statusCodeObj);
+        if (statusCodeConverter.isError(statusCode)) {
+          spanStatusBuilder.setStatus(StatusCode.ERROR);
           return;
         }
       }

instrumentation-api-semconv/src/main/java/io/opentelemetry/instrumentation/api/instrumenter/http/HttpStatusCodeConverter.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.instrumentation.api.instrumenter.http;
+
+// https://github.com/open-telemetry/semantic-conventions/blob/v1.21.0/docs/http/http-spans.md#status
+enum HttpStatusCodeConverter {
+  SERVER {
+    @Override
+    boolean isError(int responseStatusCode) {
+      return responseStatusCode >= 500
+          ||
+          // invalid status code, does not exists
+          responseStatusCode < 100;
+    }
+  },
+  CLIENT {
+    @Override
+    boolean isError(int responseStatusCode) {
+      return responseStatusCode >= 400
+          ||
+          // invalid status code, does not exists
+          responseStatusCode < 100;
+    }
+  };
+
+  abstract boolean isError(int responseStatusCode);
+}

instrumentation-api-semconv/src/main/java/io/opentelemetry/instrumentation/api/instrumenter/http/internal/HttpAttributes.java

@@ -0,0 +1,24 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.instrumentation.api.instrumenter.http.internal;
+
+import static io.opentelemetry.api.common.AttributeKey.stringKey;
+
+import io.opentelemetry.api.common.AttributeKey;
+
+/**
+ * This class is internal and is hence not for public use. Its APIs are unstable and can change at
+ * any time.
+ */
+public final class HttpAttributes {
+
+  // FIXME: remove this class and replace its usages with SemanticAttributes once schema 1.22 is
+  // released
+
+  public static final AttributeKey<String> ERROR_TYPE = stringKey("error.type");
+
+  private HttpAttributes() {}
+}