Copy makes a copy of the metadata.

Delete key from metadata.

FromContext returns metadata from the given context returned metadata shoud not be modified or race condition happens Deprecated: use FromIncomingContext or FromOutgoingContext.

FromIncomingContext returns metadata from incoming ctx returned metadata shoud not be modified or race condition happens.

FromOutgoingContext returns metadata from outgoing ctx returned metadata shoud not be modified or race condition happens.

Get returns a single value from metadata in the context.

MergeContext merges metadata to existing metadata, overwriting if specified.

NewContext creates a new context with the given metadata Deprecated: use NewIncomingContext or NewOutgoingContext.

NewIncomingContext creates a new context with incoming metadata attached.

NewOutgoingContext creates a new context with outcoming metadata attached.

Set add key with val to metadata.

SetIncomingContext modify incoming context with given metadata.

SetOutgoingContext modify outgoing context with given metadata.

Metadata is our way of representing request headers internally.