support long, double and boolean for tags from on Observation layer m…

…icrometer-metrics#234

micrometer-tracing/src/main/java/io/micrometer/tracing/TypedKeyValue.java

@@ -0,0 +1,80 @@
+/**
+ * Copyright 2022 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.micrometer.tracing;
+
+import io.micrometer.common.KeyValue;
+
+public abstract class TypedKeyValue<T> implements KeyValue {
+
+    protected final String key;
+
+    protected final T value;
+
+    TypedKeyValue(String key, T value) {
+        this.key = key;
+        this.value = value;
+    }
+
+    @Override
+    public String getKey() {
+        return key;
+    }
+
+    @Override
+    public String getValue() {
+        return String.valueOf(value);
+    }
+
+    public abstract void setAttribute(Span span);
+
+    public static TypedKeyValue<Long> of(String key, long value) {
+        return new TypedKeyValue<Long>(key, value) {
+            @Override
+            public void setAttribute(Span span) {
+                span.tag(getKey(), value);
+            }
+        };
+    }
+
+    public static TypedKeyValue<String> of(String key, String value) {
+        return new TypedKeyValue<String>(key, value) {
+            @Override
+            public void setAttribute(Span span) {
+                span.tag(getKey(), value);
+            }
+        };
+    }
+
+    public static TypedKeyValue<Double> of(String key, double value) {
+        return new TypedKeyValue<Double>(key, value) {
+            @Override
+            public void setAttribute(Span span) {
+                span.tag(getKey(), value);
+            }
+        };
+
+    }
+
+    public static TypedKeyValue<Boolean> of(String key, boolean value) {
+        return new TypedKeyValue<Boolean>(key, value) {
+            @Override
+            public void setAttribute(Span span) {
+                span.tag(getKey(), value);
+            }
+        };
+    }
+
+}

micrometer-tracing/src/main/java/io/micrometer/tracing/handler/TracingObservationHandler.java

@@ -23,10 +23,7 @@
 import io.micrometer.observation.Observation.Event;
 import io.micrometer.observation.ObservationHandler;
 import io.micrometer.observation.ObservationView;
-import io.micrometer.tracing.CurrentTraceContext;
-import io.micrometer.tracing.Span;
-import io.micrometer.tracing.TraceContext;
-import io.micrometer.tracing.Tracer;
+import io.micrometer.tracing.*;
 import io.micrometer.tracing.internal.SpanNameUtil;
 
 import java.util.Map;
@@ -48,11 +45,14 @@ public interface TracingObservationHandler<T extends Observation.Context> extend
      */
     default void tagSpan(T context, Span span) {
         for (KeyValue keyValue : context.getAllKeyValues()) {
-            if (!keyValue.getKey().equalsIgnoreCase("ERROR")) {
-                span.tag(keyValue.getKey(), keyValue.getValue());
+            if (keyValue.getKey().equalsIgnoreCase("ERROR")) {
+                span.error(new RuntimeException(keyValue.getValue()));
+            }
+            else if (keyValue instanceof TypedKeyValue) {
+                ((TypedKeyValue<?>) keyValue).setAttribute(span);
             }
             else {
-                span.error(new RuntimeException(keyValue.getValue()));
+                span.tag(keyValue.getKey(), keyValue.getValue());
             }
         }
     }