jooby-opentelemetry: repeated request header causes 400 (TypeMismatch…

jooby/src/main/java/io/jooby/internal/HeadersValue.java

@@ -30,7 +30,7 @@ protected Map<String, Value> hash() {
   @Override
   public Map<String, String> toMap() {
     Map<String, String> map = new TreeMap<>(String.CASE_INSENSITIVE_ORDER);
-    toMultimap().forEach((k, v) -> map.put(k, v.get(0)));
+    toMultimap().forEach((k, v) -> map.put(k, v.getFirst()));
     return map;
   }
 

modules/jooby-opentelemetry/src/main/java/io/jooby/internal/opentelemetry/DefaultOtelContextExtractor.java

@@ -7,6 +7,8 @@
 
 import static io.opentelemetry.context.Context.current;
 
+import java.util.Iterator;
+
 import org.jspecify.annotations.NonNull;
 
 import io.jooby.opentelemetry.OtelContextExtractor;
@@ -52,8 +54,14 @@ public Iterable<String> keys(io.jooby.Context ctx) {
 
     @Override
     public String get(io.jooby.Context ctx, String key) {
+      var value = ctx.header(key).toList();
       // Safely extract the header value, returning null if it doesn't exist
-      return ctx.header(key).valueOrNull();
+      return value.isEmpty() ? null : value.getFirst();
+    }
+
+    @Override
+    public Iterator<String> getAll(io.jooby.Context ctx, String key) {
+      return ctx.header(key).toList().iterator();
     }
   }
 }

modules/jooby-opentelemetry/src/test/java/io/jooby/internal/opentelemetry/DefaultOtelContextExtractorTest.java

@@ -14,6 +14,7 @@
 import static org.mockito.Mockito.verifyNoInteractions;
 import static org.mockito.Mockito.when;
 
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
@@ -108,8 +109,8 @@ void joobyRequestGetterShouldReturnHeaderKeys() {
   void joobyRequestGetterShouldReturnHeaderValueOrNull() {
     // Arrange
     Value mockHeaderValue = mock(Value.class);
-    when(mockHeaderValue.valueOrNull())
-        .thenReturn("00-0af7651916cd43dd8448eb211c80319c-b7ad6b7169203331-01");
+    when(mockHeaderValue.toList())
+        .thenReturn(List.of("00-0af7651916cd43dd8448eb211c80319c-b7ad6b7169203331-01"));
     when(joobyCtx.header("traceparent")).thenReturn(mockHeaderValue);
 
     // Act

modules/jooby-opentelemetry/src/test/java/io/jooby/internal/opentelemetry/DefaultOtelContextHeadersExtractorTest.java

@@ -0,0 +1,86 @@
+/*
+ * Jooby https://jooby.io
+ * Apache License Version 2.0 https://jooby.io/LICENSE.txt
+ * Copyright 2014 Edgar Espina
+ */
+package io.jooby.internal.opentelemetry;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import java.util.List;
+import java.util.Map;
+
+import org.junit.jupiter.api.Test;
+
+import io.jooby.Context;
+import io.jooby.value.Value;
+import io.jooby.value.ValueFactory;
+
+class DefaultOtelContextHeadersExtractorTest {
+
+  @Test
+  void shouldExtractKeys() {
+    var ctx = mock(io.jooby.Context.class);
+    when(ctx.headerMap())
+        .thenReturn(
+            Map.of("traceparent", "00-0af7651916cd43dd8448eb211c80319c-b7ad6b7169203331-01"));
+    var headers = DefaultOtelContextExtractor.Headers.INSTANCE;
+    headers.keys(ctx);
+  }
+
+  @Test
+  void shouldExtractHeaderValue() {
+    var ctx = mock(io.jooby.Context.class);
+    var headerValue = mock(io.jooby.value.Value.class);
+    when(headerValue.toList())
+        .thenReturn(java.util.List.of("00-0af7651916cd43dd8448eb211c80319c-b7ad6b7169203331-01"));
+    when(ctx.header("traceparent")).thenReturn(headerValue);
+    var headers = DefaultOtelContextExtractor.Headers.INSTANCE;
+    headers.get(ctx, "traceparent");
+  }
+
+  @Test
+  void shouldExtractHeaderRealSingleValue() {
+    var ctx = mock(io.jooby.Context.class);
+    var firstValue = "00-0af7651916cd43dd8448eb211c80319c-b7ad6b7169203331-01";
+    var headerValue = Value.value(new ValueFactory(), "traceparent", firstValue);
+    when(ctx.header("traceparent")).thenReturn(headerValue);
+    var headers = DefaultOtelContextExtractor.Headers.INSTANCE;
+    assertEquals(firstValue, headers.get(ctx, "traceparent"));
+  }
+
+  @Test
+  void shouldExtractHeaderRealListValue() {
+    var ctx = mock(io.jooby.Context.class);
+    var firstValue = "00-0af7651916cd43dd8448eb211c80319c-b7ad6b7169203331-01";
+    var secondValue = "00-0af7651916cd43dd8448eb211c80319c-b7ad6b7169203331-02";
+    var headerValue =
+        Value.array(new ValueFactory(), "traceparent", List.of(firstValue, secondValue));
+    when(ctx.header("traceparent")).thenReturn(headerValue);
+    var headers = DefaultOtelContextExtractor.Headers.INSTANCE;
+    assertEquals(firstValue, headers.get(ctx, "traceparent"));
+  }
+
+  @Test
+  void shouldExtractHeaderRealEmptyValue() {
+    var ctx = mock(io.jooby.Context.class);
+    var headerValue = Value.missing(new ValueFactory(), "traceparent");
+    when(ctx.header("traceparent")).thenReturn(headerValue);
+    var headers = DefaultOtelContextExtractor.Headers.INSTANCE;
+    assertEquals(null, headers.get(ctx, "traceparent"));
+  }
+
+  @Test
+  void shouldExtractHeaderAllValue() {
+    var ctx = mock(Context.class);
+    var headerValue = mock(Value.class);
+    var values = List.of("00-0af7651916cd43dd8448eb211c80319c-b7ad6b7169203331-01");
+    when(headerValue.toList()).thenReturn(values);
+    when(ctx.header("traceparent")).thenReturn(headerValue);
+    var headers = DefaultOtelContextExtractor.Headers.INSTANCE;
+    assertThat(headers.getAll(ctx, "traceparent")).toIterable().containsExactlyElementsOf(values);
+  }
+}