syntax = "proto3";

package opentelemetry.collector.exporter.exporterhelper.internal.queue;

option go_package = "go.opentelemetry.io/collector/exporter/exporterhelper/internal/queue";

// PersistentMetadata holds all persistent metadata for the queue.
// The items and bytes sizes are recorded explicitly,
// the requests size can be calculated as (write_index - read_index + len(currently_dispatched_items)).
message PersistentMetadata{
  // Current total items size of the queue.
  sfixed64 items_size = 1;

  // Current total bytes size of the queue.
  sfixed64 bytes_size = 2;

  // Index of the next item to be read from the queue.
  fixed64 read_index = 3;

  // Index where the next item will be written to the queue.
  fixed64 write_index = 4;

  // List of item indices currently being processed by consumers.
  repeated fixed64 currently_dispatched_items = 5;
}