Add Getter.Keys() with Jaeger Baggage support.

api/src/jmh/java/io/opentelemetry/api/trace/propagation/HttpTraceContextExtractBenchmark.java

@@ -40,6 +40,11 @@ public class HttpTraceContextExtractBenchmark {
   private final HttpTraceContext httpTraceContext = HttpTraceContext.getInstance();
   private final Getter<Map<String, String>> getter =
       new Getter<Map<String, String>>() {
+        @Override
+        public Iterable<String> keys(Map<String, String> carrier) {
+          return carrier.keySet();
+        }
+
         @Override
         public String get(Map<String, String> carrier, String key) {
           return carrier.get(key);

api/src/test/java/io/opentelemetry/api/baggage/propagation/W3CBaggagePropagatorFuzzTest.java

@@ -11,7 +11,9 @@
 import edu.berkeley.cs.jqf.fuzz.Fuzz;
 import edu.berkeley.cs.jqf.fuzz.JQF;
 import io.opentelemetry.context.Context;
+import io.opentelemetry.context.propagation.TextMapPropagator.Getter;
 import java.util.Map;
+import javax.annotation.Nullable;
 import org.junit.runner.RunWith;
 
 @RunWith(JQF.class)
@@ -22,7 +24,21 @@ public class W3CBaggagePropagatorFuzzTest {
   @Fuzz
   public void safeForRandomInputs(String baggage) {
     Context context =
-        baggagePropagator.extract(Context.root(), ImmutableMap.of("baggage", baggage), Map::get);
+        baggagePropagator.extract(
+            Context.root(),
+            ImmutableMap.of("baggage", baggage),
+            new Getter<Map<String, String>>() {
+              @Override
+              public Iterable<String> keys(Map<String, String> carrier) {
+                return carrier.keySet();
+              }
+
+              @Nullable
+              @Override
+              public String get(Map<String, String> carrier, String key) {
+                return carrier.get(key);
+              }
+            });
     assertThat(context).isNotNull();
   }
 }

api/src/test/java/io/opentelemetry/api/baggage/propagation/W3CBaggagePropagatorTest.java

@@ -12,12 +12,28 @@
 import io.opentelemetry.api.baggage.Baggage;
 import io.opentelemetry.api.baggage.EntryMetadata;
 import io.opentelemetry.context.Context;
+import io.opentelemetry.context.propagation.TextMapPropagator.Getter;
 import java.util.HashMap;
 import java.util.Map;
+import javax.annotation.Nullable;
 import org.junit.jupiter.api.Test;
 
 class W3CBaggagePropagatorTest {
 
+  private static final Getter<Map<String, String>> getter =
+      new Getter<Map<String, String>>() {
+        @Override
+        public Iterable<String> keys(Map<String, String> carrier) {
+          return carrier.keySet();
+        }
+
+        @Nullable
+        @Override
+        public String get(Map<String, String> carrier, String key) {
+          return carrier.get(key);
+        }
+      };
+
   @Test
   void fields() {
     assertThat(W3CBaggagePropagator.getInstance().fields()).containsExactly("baggage");
@@ -27,8 +43,7 @@ void fields() {
   void extract_noBaggageHeader() {
     W3CBaggagePropagator propagator = W3CBaggagePropagator.getInstance();
 
-    Context result =
-        propagator.extract(Context.root(), ImmutableMap.<String, String>of(), Map::get);
+    Context result = propagator.extract(Context.root(), ImmutableMap.<String, String>of(), getter);
 
     assertThat(result).isEqualTo(Context.root());
   }
@@ -37,8 +52,7 @@ void extract_noBaggageHeader() {
   void extract_emptyBaggageHeader() {
     W3CBaggagePropagator propagator = W3CBaggagePropagator.getInstance();
 
-    Context result =
-        propagator.extract(Context.root(), ImmutableMap.of("baggage", ""), ImmutableMap::get);
+    Context result = propagator.extract(Context.root(), ImmutableMap.of("baggage", ""), getter);
 
     assertThat(Baggage.fromContext(result)).isEqualTo(Baggage.empty());
   }
@@ -48,8 +62,7 @@ void extract_singleEntry() {
     W3CBaggagePropagator propagator = W3CBaggagePropagator.getInstance();
 
     Context result =
-        propagator.extract(
-            Context.root(), ImmutableMap.of("baggage", "key=value"), ImmutableMap::get);
+        propagator.extract(Context.root(), ImmutableMap.of("baggage", "key=value"), getter);
 
     Baggage expectedBaggage = Baggage.builder().put("key", "value").build();
     assertThat(Baggage.fromContext(result)).isEqualTo(expectedBaggage);
@@ -61,9 +74,7 @@ void extract_multiEntry() {
 
     Context result =
         propagator.extract(
-            Context.root(),
-            ImmutableMap.of("baggage", "key1=value1,key2=value2"),
-            ImmutableMap::get);
+            Context.root(), ImmutableMap.of("baggage", "key1=value1,key2=value2"), getter);
 
     Baggage expectedBaggage = Baggage.builder().put("key1", "value1").put("key2", "value2").build();
     assertThat(Baggage.fromContext(result)).isEqualTo(expectedBaggage);
@@ -75,7 +86,7 @@ void extract_duplicateKeys() {
 
     Context result =
         propagator.extract(
-            Context.root(), ImmutableMap.of("baggage", "key=value1,key=value2"), ImmutableMap::get);
+            Context.root(), ImmutableMap.of("baggage", "key=value1,key=value2"), getter);
 
     Baggage expectedBaggage = Baggage.builder().put("key", "value2").build();
     assertThat(Baggage.fromContext(result)).isEqualTo(expectedBaggage);
@@ -89,7 +100,7 @@ void extract_withMetadata() {
         propagator.extract(
             Context.root(),
             ImmutableMap.of("baggage", "key=value;metadata-key=value;othermetadata"),
-            ImmutableMap::get);
+            getter);
 
     Baggage expectedBaggage =
         Baggage.builder()
@@ -109,7 +120,7 @@ void extract_fullComplexities() {
                 "baggage",
                 "key1= value1; metadata-key = value; othermetadata, "
                     + "key2 =value2 , key3 =\tvalue3 ; "),
-            ImmutableMap::get);
+            getter);
 
     Baggage expectedBaggage =
         Baggage.builder()
@@ -135,7 +146,7 @@ void extract_invalidHeader() {
                 "baggage",
                 "key1= v;alsdf;-asdflkjasdf===asdlfkjadsf ,,a sdf9asdf-alue1; metadata-key = "
                     + "value; othermetadata, key2 =value2 , key3 =\tvalue3 ; "),
-            ImmutableMap::get);
+            getter);
 
     assertThat(Baggage.fromContext(result)).isEqualTo(Baggage.empty());
   }

api/src/test/java/io/opentelemetry/api/trace/propagation/HttpTraceContextFuzzTest.java

@@ -11,7 +11,9 @@
 import edu.berkeley.cs.jqf.fuzz.Fuzz;
 import edu.berkeley.cs.jqf.fuzz.JQF;
 import io.opentelemetry.context.Context;
+import io.opentelemetry.context.propagation.TextMapPropagator.Getter;
 import java.util.Map;
+import javax.annotation.Nullable;
 import org.junit.runner.RunWith;
 
 @RunWith(JQF.class)
@@ -25,7 +27,19 @@ public void safeForRandomInputs(String traceParentHeader, String traceStateHeade
         httpTraceContext.extract(
             Context.root(),
             ImmutableMap.of("traceparent", traceParentHeader, "tracestate", traceStateHeader),
-            Map::get);
+            new Getter<Map<String, String>>() {
+              @Override
+              public Iterable<String> keys(Map<String, String> carrier) {
+                return carrier.keySet();
+              }
+
+              @Nullable
+              @Override
+              public String get(Map<String, String> carrier, String key) {
+                return carrier.get(key);
+              }
+            });
+
     assertThat(context).isNotNull();
   }
 }

api/src/test/java/io/opentelemetry/api/trace/propagation/HttpTraceContextTest.java

@@ -23,6 +23,7 @@
 import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.Map;
+import javax.annotation.Nullable;
 import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link HttpTraceContext}. */
@@ -39,7 +40,19 @@ class HttpTraceContextTest {
   private static final String TRACEPARENT_HEADER_NOT_SAMPLED =
       "00-" + TRACE_ID_BASE16 + "-" + SPAN_ID_BASE16 + "-00";
   private static final Setter<Map<String, String>> setter = Map::put;
-  private static final Getter<Map<String, String>> getter = Map::get;
+  private static final Getter<Map<String, String>> getter =
+      new Getter<Map<String, String>>() {
+        @Override
+        public Iterable<String> keys(Map<String, String> carrier) {
+          return carrier.keySet();
+        }
+
+        @Nullable
+        @Override
+        public String get(Map<String, String> carrier, String key) {
+          return carrier.get(key);
+        }
+      };
   // Encoding preserves the order which is the reverse order of adding.
   private static final String TRACESTATE_NOT_DEFAULT_ENCODING = "bar=baz,foo=bar";
   private static final String TRACESTATE_NOT_DEFAULT_ENCODING_WITH_SPACES =
@@ -151,7 +164,7 @@ void extract_Nothing() {
     // Context remains untouched.
     assertThat(
             httpTraceContext.extract(
-                Context.current(), Collections.<String, String>emptyMap(), Map::get))
+                Context.current(), Collections.<String, String>emptyMap(), getter))
         .isSameAs(Context.current());
   }
 
@@ -169,9 +182,7 @@ void extract_SampledContext() {
   void extract_NullCarrier() {
     Map<String, String> carrier = new LinkedHashMap<>();
     carrier.put(TRACE_PARENT, TRACEPARENT_HEADER_SAMPLED);
-    assertThat(
-            getSpanContext(
-                httpTraceContext.extract(Context.current(), null, (c, k) -> carrier.get(k))))
+    assertThat(getSpanContext(httpTraceContext.extract(Context.current(), carrier, getter)))
         .isEqualTo(
             SpanContext.createFromRemoteParent(
                 TRACE_ID_BASE16, SPAN_ID_BASE16, SAMPLED_TRACE_OPTIONS, TRACE_STATE_DEFAULT));

context/src/main/java/io/opentelemetry/context/propagation/TextMapPropagator.java

@@ -115,6 +115,14 @@ interface Setter<C> {
    */
   interface Getter<C> {
 
+    /**
+     * Returns all the keys in the given carrier.
+     *
+     * @param carrier carrier of propagation fields, such as an http request.
+     * @since 0.10.0
+     */
+    Iterable<String> keys(C carrier);
+
     /**
      * Returns the first value of the given propagation {@code key} or returns {@code null}.
      *

context/src/test/java/io/opentelemetry/context/propagation/DefaultPropagatorsTest.java

@@ -155,6 +155,11 @@ private MapSetter() {}
   private static final class MapGetter implements TextMapPropagator.Getter<Map<String, String>> {
     private static final MapGetter INSTANCE = new MapGetter();
 
+    @Override
+    public Iterable<String> keys(Map<String, String> map) {
+      return map.keySet();
+    }
+
     @Override
     public String get(Map<String, String> map, String key) {
       return map.get(key);

extensions/trace-propagators/src/jmh/java/io/opentelemetry/extension/trace/propagation/PropagatorContextExtractBenchmark.java

@@ -94,6 +94,11 @@ public static class JaegerContextExtractBenchmark extends AbstractContextExtract
 
     private final TextMapPropagator.Getter<Map<String, String>> getter =
         new TextMapPropagator.Getter<Map<String, String>>() {
+          @Override
+          public Iterable<String> keys(Map<String, String> carrier) {
+            return carrier.keySet();
+          }
+
           @Override
           public String get(Map<String, String> carrier, String key) {
             return carrier.get(key);
@@ -137,6 +142,11 @@ public static class JaegerUrlEncodedContextExtractBenchmark
 
     private final TextMapPropagator.Getter<Map<String, String>> getter =
         new TextMapPropagator.Getter<Map<String, String>>() {
+          @Override
+          public Iterable<String> keys(Map<String, String> carrier) {
+            return carrier.keySet();
+          }
+
           @Override
           public String get(Map<String, String> carrier, String key) {
             return carrier.get(key);
@@ -180,6 +190,11 @@ public static class B3SingleHeaderContextExtractBenchmark
 
     private final TextMapPropagator.Getter<Map<String, String>> getter =
         new TextMapPropagator.Getter<Map<String, String>>() {
+          @Override
+          public Iterable<String> keys(Map<String, String> carrier) {
+            return carrier.keySet();
+          }
+
           @Override
           public String get(Map<String, String> carrier, String key) {
             return carrier.get(key);
@@ -226,6 +241,11 @@ private static Map<String, String> createHeaders(
 
     private final TextMapPropagator.Getter<Map<String, String>> getter =
         new TextMapPropagator.Getter<Map<String, String>>() {
+          @Override
+          public Iterable<String> keys(Map<String, String> carrier) {
+            return carrier.keySet();
+          }
+
           @Override
           public String get(Map<String, String> carrier, String key) {
             return carrier.get(key);