The default read-only implementation of BinaryAnnotation.
This Proxy trait allows you to extend the BinaryAnnotation trait with additional state or behavior and implement the read-only methods from BinaryAnnotation using an underlying instance.
Field information in declaration order.
Checks that all required fields are non-null.
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 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.