1 files changed, 147 insertions, 0 deletions
diff --git a/impl_core/src/test/java/io/opencensus/implcore/tags/propagation/TagContextSerializationTest.java b/impl_core/src/test/java/io/opencensus/implcore/tags/propagation/TagContextSerializationTest.java
new file mode 100644
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--- /dev/null
+++ b/impl_core/src/test/java/io/opencensus/implcore/tags/propagation/TagContextSerializationTest.java
@@ -0,0 +1,147 @@
+/*
+ * Copyright 2016-17, OpenCensus 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
+ *
+ *     http://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.opencensus.implcore.tags.propagation;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import com.google.common.base.Charsets;
+import com.google.common.collect.Collections2;
+import io.opencensus.implcore.internal.VarInt;
+import io.opencensus.implcore.tags.TagsComponentImplBase;
+import io.opencensus.tags.Tag;
+import io.opencensus.tags.TagContext;
+import io.opencensus.tags.TagContextBuilder;
+import io.opencensus.tags.TagKey;
+import io.opencensus.tags.TagValue;
+import io.opencensus.tags.Tagger;
+import io.opencensus.tags.TagsComponent;
+import io.opencensus.tags.propagation.TagContextBinarySerializer;
+import io.opencensus.tags.propagation.TagContextSerializationException;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/**
+ * Tests for serializing tags with {@link SerializationUtils} and {@link
+ * TagContextBinarySerializerImpl}.
+ */
+@RunWith(JUnit4.class)
+public class TagContextSerializationTest {
+
+  @Rule public final ExpectedException thrown = ExpectedException.none();
+
+  private static final TagKey K1 = TagKey.create("k1");
+  private static final TagKey K2 = TagKey.create("k2");
+  private static final TagKey K3 = TagKey.create("k3");
+  private static final TagKey K4 = TagKey.create("k4");
+
+  private static final TagValue V1 = TagValue.create("v1");
+  private static final TagValue V2 = TagValue.create("v2");
+  private static final TagValue V3 = TagValue.create("v3");
+  private static final TagValue V4 = TagValue.create("v4");
+
+  private static final Tag T1 = Tag.create(K1, V1);
+  private static final Tag T2 = Tag.create(K2, V2);
+  private static final Tag T3 = Tag.create(K3, V3);
+  private static final Tag T4 = Tag.create(K4, V4);
+
+  private final TagsComponent tagsComponent = new TagsComponentImplBase();
+  private final TagContextBinarySerializer serializer =
+      tagsComponent.getTagPropagationComponent().getBinarySerializer();
+  private final Tagger tagger = tagsComponent.getTagger();
+
+  @Test
+  public void testSerializeDefault() throws Exception {
+    testSerialize();
+  }
+
+  @Test
+  public void testSerializeWithOneTag() throws Exception {
+    testSerialize(T1);
+  }
+
+  @Test
+  public void testSerializeWithMultipleTags() throws Exception {
+    testSerialize(T1, T2, T3, T4);
+  }
+
+  @Test
+  public void testSerializeTooLargeTagContext() throws TagContextSerializationException {
+    TagContextBuilder builder = tagger.emptyBuilder();
+    for (int i = 0; i < SerializationUtils.TAGCONTEXT_SERIALIZED_SIZE_LIMIT / 8 - 1; i++) {
+      // Each tag will be with format {key : "0123", value : "0123"}, so the length of it is 8.
+      String str;
+      if (i < 10) {
+        str = "000" + i;
+      } else if (i < 100) {
+        str = "00" + i;
+      } else if (i < 1000) {
+        str = "0" + i;
+      } else {
+        str = String.valueOf(i);
+      }
+      builder.put(TagKey.create(str), TagValue.create(str));
+    }
+    // The last tag will be of size 9, so the total size of the TagContext (8193) will be one byte
+    // more than limit.
+    builder.put(TagKey.create("last"), TagValue.create("last1"));
+
+    TagContext tagContext = builder.build();
+    thrown.expect(TagContextSerializationException.class);
+    thrown.expectMessage("Size of TagContext exceeds the maximum serialized size ");
+    serializer.toByteArray(tagContext);
+  }
+
+  private void testSerialize(Tag... tags) throws IOException, TagContextSerializationException {
+    TagContextBuilder builder = tagger.emptyBuilder();
+    for (Tag tag : tags) {
+      builder.put(tag.getKey(), tag.getValue());
+    }
+
+    byte[] actual = serializer.toByteArray(builder.build());
+
+    Collection<List<Tag>> tagPermutation = Collections2.permutations(Arrays.asList(tags));
+    Set<String> possibleOutputs = new HashSet<String>();
+    for (List<Tag> list : tagPermutation) {
+      ByteArrayOutputStream expected = new ByteArrayOutputStream();
+      expected.write(SerializationUtils.VERSION_ID);
+      for (Tag tag : list) {
+        expected.write(SerializationUtils.TAG_FIELD_ID);
+        encodeString(tag.getKey().getName(), expected);
+        encodeString(tag.getValue().asString(), expected);
+      }
+      possibleOutputs.add(new String(expected.toByteArray(), Charsets.UTF_8));
+    }
+
+    assertThat(possibleOutputs).contains(new String(actual, Charsets.UTF_8));
+  }
+
+  private static void encodeString(String input, ByteArrayOutputStream byteArrayOutputStream)
+      throws IOException {
+    VarInt.putVarInt(input.length(), byteArrayOutputStream);
+    byteArrayOutputStream.write(input.getBytes(Charsets.UTF_8));
+  }
+}