io.zipkin

Class BinaryAnnotation

java.lang.Object

io.zipkin.BinaryAnnotation

public final class BinaryAnnotation
extends Object

Binary annotations are tags applied to a Span to give it context. For example, a binary annotation of "http.uri" could the path to a resource in a RPC call.

Binary annotations of type BinaryAnnotation.Type.STRING are always queryable, though more a historical implementation detail than a structural concern.

Binary annotations can repeat, and vary on the host. Similar to Annotation, the host indicates who logged the event. This allows you to tell the difference between the client and server side of the same key. For example, the key "http.uri" might be different on the client and server side due to rewriting, like "/api/v1/myresource" vs "/myresource. Via the host field, you can see the different points of view, which often help in debugging.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	BinaryAnnotation.Builder
static class	BinaryAnnotation.Type A subset of thrift base types, except BYTES.

Field Summary

Fields

Modifier and Type	Field and Description
Endpoint	endpoint The host that recorded value, allowing query by service name or address.
String	key Name used to lookup spans, such as "http.uri" or "finagle.version".
BinaryAnnotation.Type	type The thrift type of value, most often STRING.
byte[]	value Serialized thrift bytes, in TBinaryProtocol format.

Method Summary

Modifier and Type	Method and Description
static BinaryAnnotation	address(String key, Endpoint endpoint) Special-cased form supporting Constants.CLIENT_ADDR and Constants.SERVER_ADDR.
static BinaryAnnotation	create(String key, byte[] value, BinaryAnnotation.Type type, Endpoint endpoint)
static BinaryAnnotation	create(String key, String value, Endpoint endpoint) String values are the only queryable type of binary annotation.
boolean	equals(Object o)
int	hashCode()
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

key

public final String key

Name used to lookup spans, such as "http.uri" or "finagle.version".

value

public final byte[] value

Serialized thrift bytes, in TBinaryProtocol format.

For legacy reasons, byte order is big-endian. See THRIFT-3217.

type

public final BinaryAnnotation.Type type

The thrift type of value, most often STRING.

Note: type shouldn't vary for the same key.

endpoint

@Nullable
public final Endpoint endpoint

The host that recorded value, allowing query by service name or address.

There are two exceptions: when key is Constants.CLIENT_ADDR or Constants.SERVER_ADDR, this is the source or destination of an RPC. This exception allows zipkin to display network context of uninstrumented services, such as browsers or databases.

Method Detail

address

public static BinaryAnnotation address(String key,
                                       Endpoint endpoint)

Special-cased form supporting Constants.CLIENT_ADDR and Constants.SERVER_ADDR.

Parameters:

key - Constants.CLIENT_ADDR or Constants.SERVER_ADDR

endpoint - associated endpoint.

create

public static BinaryAnnotation create(String key,
                                      String value,
                                      @Nullable
                                      Endpoint endpoint)

String values are the only queryable type of binary annotation.

create

public static BinaryAnnotation create(String key,
                                      byte[] value,
                                      BinaryAnnotation.Type type,
                                      @Nullable
                                      Endpoint endpoint)

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object