gRPC metadata headers

YDB uses the following gRPC metadata headers:

• gRPC headers which a client sends to YDB:

  • x-ydb-database - database
  • x-ydb-auth-ticket - auth token from a credentials provider
  • x-ydb-sdk-build-info - YDB SDK build info
  • x-ydb-trace-id - user-defined request ID. If not defined by client YDB SDK generates automatically using UUID format
  • x-ydb-application-name - optional user-defined application name
  • x-ydb-client-capabilities - supported client SDK capabilities (session-balancer and other)
  • x-ydb-client-pid - client application process ID
  • traceparent - OpenTelemetry trace ID (specification)

• gRPC headers which YDB sends to client with responses:

  • x-ydb-server-hints - notifications from YDB (such as session-close and other)
  • x-ydb-consumed-units - consumed units on the current request