Merge remote-tracking branch 'aosp/upstream-master' into merge am: dd3cabeacc

am: 6fbc3cf5a1

Change-Id: I11b0ec1cf561d2a14da78e444b1594f167787fe6

4 files changed, 191 insertions, 0 deletions

diff --git a/api/src/main/java/io/opencensus/tags/propagation/TagContextBinarySerializer.java b/api/src/main/java/io/opencensus/tags/propagation/TagContextBinarySerializer.java
new file mode 100644
index 00000000..39eb8cee
--- /dev/null
+++ b/api/src/main/java/io/opencensus/tags/propagation/TagContextBinarySerializer.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2017, 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.tags.propagation;
+
+import io.opencensus.tags.TagContext;
+
+/**
+ * Object for serializing and deserializing {@link TagContext}s with the binary format.
+ *
+ * <p>See <a
+ * href="https://github.com/census-instrumentation/opencensus-specs/blob/master/encodings/BinaryEncoding.md#tag-context">opencensus-specs</a>
+ * for the specification of the cross-language binary serialization format.
+ *
+ * @since 0.8
+ */
+public abstract class TagContextBinarySerializer {
+
+  /**
+   * Serializes the {@code TagContext} into the on-the-wire representation.
+   *
+   * <p>This method should be the inverse of {@link #fromByteArray}.
+   *
+   * @param tags the {@code TagContext} to serialize.
+   * @return the on-the-wire representation of a {@code TagContext}.
+   * @throws TagContextSerializationException if the result would be larger than the maximum allowed
+   *     serialized size.
+   * @since 0.8
+   */
+  public abstract byte[] toByteArray(TagContext tags) throws TagContextSerializationException;
+
+  /**
+   * Creates a {@code TagContext} from the given on-the-wire encoded representation.
+   *
+   * <p>This method should be the inverse of {@link #toByteArray}.
+   *
+   * @param bytes on-the-wire representation of a {@code TagContext}.
+   * @return a {@code TagContext} deserialized from {@code bytes}.
+   * @throws TagContextDeserializationException if there is a parse error, the input contains
+   *     invalid tags, or the input is larger than the maximum allowed serialized size.
+   * @since 0.8
+   */
+  public abstract TagContext fromByteArray(byte[] bytes) throws TagContextDeserializationException;
+}
diff --git a/api/src/main/java/io/opencensus/tags/propagation/TagContextDeserializationException.java b/api/src/main/java/io/opencensus/tags/propagation/TagContextDeserializationException.java
new file mode 100644
index 00000000..11dcb59f
--- /dev/null
+++ b/api/src/main/java/io/opencensus/tags/propagation/TagContextDeserializationException.java
@@ -0,0 +1,49 @@
+/*
+ * Copyright 2017, 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.tags.propagation;
+
+import io.opencensus.tags.TagContext;
+
+/**
+ * Exception thrown when a {@link TagContext} cannot be parsed.
+ *
+ * @since 0.8
+ */
+public final class TagContextDeserializationException extends Exception {
+  private static final long serialVersionUID = 0L;
+
+  /**
+   * Constructs a new {@code TagContextParseException} with the given message.
+   *
+   * @param message a message describing the error.
+   * @since 0.8
+   */
+  public TagContextDeserializationException(String message) {
+    super(message);
+  }
+
+  /**
+   * Constructs a new {@code TagContextParseException} with the given message and cause.
+   *
+   * @param message a message describing the error.
+   * @param cause the cause of the error.
+   * @since 0.8
+   */
+  public TagContextDeserializationException(String message, Throwable cause) {
+    super(message, cause);
+  }
+}
diff --git a/api/src/main/java/io/opencensus/tags/propagation/TagContextSerializationException.java b/api/src/main/java/io/opencensus/tags/propagation/TagContextSerializationException.java
new file mode 100644
index 00000000..bb3c9b74
--- /dev/null
+++ b/api/src/main/java/io/opencensus/tags/propagation/TagContextSerializationException.java
@@ -0,0 +1,49 @@
+/*
+ * Copyright 2017, 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.tags.propagation;
+
+import io.opencensus.tags.TagContext;
+
+/**
+ * Exception thrown when a {@link TagContext} cannot be serialized.
+ *
+ * @since 0.8
+ */
+public final class TagContextSerializationException extends Exception {
+  private static final long serialVersionUID = 0L;
+
+  /**
+   * Constructs a new {@code TagContextSerializationException} with the given message.
+   *
+   * @param message a message describing the error.
+   * @since 0.8
+   */
+  public TagContextSerializationException(String message) {
+    super(message);
+  }
+
+  /**
+   * Constructs a new {@code TagContextSerializationException} with the given message and cause.
+   *
+   * @param message a message describing the error.
+   * @param cause the cause of the error.
+   * @since 0.8
+   */
+  public TagContextSerializationException(String message, Throwable cause) {
+    super(message, cause);
+  }
+}
diff --git a/api/src/main/java/io/opencensus/tags/propagation/TagPropagationComponent.java b/api/src/main/java/io/opencensus/tags/propagation/TagPropagationComponent.java
new file mode 100644
index 00000000..6ececa79
--- /dev/null
+++ b/api/src/main/java/io/opencensus/tags/propagation/TagPropagationComponent.java
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2017, 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.tags.propagation;
+
+import io.opencensus.tags.TagContext;
+
+/**
+ * Object containing all supported {@link TagContext} propagation formats.
+ *
+ * @since 0.8
+ */
+// TODO(sebright): Add an HTTP serializer.
+public abstract class TagPropagationComponent {
+
+  /**
+   * Returns the {@link TagContextBinarySerializer} for this implementation.
+   *
+   * @return the {@code TagContextBinarySerializer} for this implementation.
+   * @since 0.8
+   */
+  public abstract TagContextBinarySerializer getBinarySerializer();
+}