// DescribeGroupsRequest requests metadata for group IDs.
DescribeGroupsRequest => key 15, max version 5, flexible v5+, group coordinator
  // Groups is an array of group IDs to request metadata for.
  Groups: [string]
  // IncludeAuthorizedOperations, introduced in Kafka 2.3.0, specifies
  // whether to include a bitfield of AclOperations this client can perform
  // on the groups. See KIP-430 for more details.
  IncludeAuthorizedOperations: bool // v3+

// DescribeGroupsResponse is returned from a DescribeGroupsRequest.
DescribeGroupsResponse =>
  ThrottleMillis(2) // v1+
  // Groups is an array of group metadata.
  Groups: [=>]
    // ErrorCode is the error code for an individual group in a request.
    //
    // GROUP_AUTHORIZATION_FAILED is returned if the client is not authorized
    // to describe a group.
    //
    // INVALID_GROUP_ID is returned if the requested group ID is invalid.
    //
    // COORDINATOR_NOT_AVAILABLE is returned if the coordinator for this
    // group is not yet active.
    //
    // COORDINATOR_LOAD_IN_PROGRESS is returned if the group is loading.
    //
    // NOT_COORDINATOR is returned if the requested broker is not the
    // coordinator for this group.
    ErrorCode: int16
    // Group is the id of this group.
    Group: string
    // State is the state this group is in.
    State: string
    // ProtocolType is the "type" of protocol being used for this group.
    ProtocolType: string
    // Protocol is the agreed upon protocol for all members in this group.
    Protocol: string
    // Members contains members in this group.
    Members: [=>]
      // MemberID is the member ID of a member in this group.
      MemberID: string
      // InstanceID is the instance ID of this member in the group (KIP-345).
      InstanceID: nullable-string // v4+
      // ClientID is the client ID used by this member.
      ClientID: string
      // ClientHost is the host this client is running on.
      ClientHost: string
      // ProtocolMetadata is the metadata this member included when joining
      // the group. If using normal (Java-like) consumers, this will be of
      // type GroupMemberMetadata.
      ProtocolMetadata: bytes
      // MemberAssignment is the assignment for this member in the group.
      // If using normal (Java-like) consumers, this will be of type
      // GroupMemberAssignment.
      MemberAssignment: bytes
    // AuthorizedOperations is a bitfield containing which operations the
    // the client is allowed to perform on this group.
    // This is only returned if requested.
    AuthorizedOperations: int32(-2147483648) // v3+