edition = "2023";
package grpc;

option go_package = "github.com/pbinitiative/zenbpm/internal/grpc/proto";

service ZenBpm {
  rpc JobStream(stream JobStreamRequest) returns (stream JobStreamResponse);
}

message JobStreamRequest{
  oneof request{
    StreamSubscriptionRequest subscription = 1;
    JobCompleteRequest complete = 2;
    JobFailRequest fail = 3;
  }
}

message StreamSubscriptionRequest{
  enum Type {
    TYPE_UNDEFINED = 0; 
    TYPE_SUBSCRIBE = 1; // subscribe client to provided job_type
    TYPE_UNSUBSCRIBE = 2; // unsubscribe client from provided job_type
  }
  string job_type = 1;
  Type type = 2;
  // int32 lock_duration = 3; // the duration in ms that the job will be locked for completion only by client_id
  // int32 max_active_jobs = 4; // maximum active jobs of provided job_type for current stream and client_id, uniqueness across streams is not guaranteed as new streams can reach different node in the cluster.
}

message JobCompleteRequest{
  int64 key = 1; // job key
  bytes variables = 2; // json variables 
}

message JobFailRequest{
  int64 key = 1;
  string message = 2;
  string error_code = 3;
  bytes variables = 4;
}

message JobStreamResponse {
  ErrorResult error = 1;
  WaitingJob job = 2;
}

message WaitingJob {
  int64 key = 1;
  int64 instance_key = 2;
  bytes variables = 3;
  string type = 4;
  string element_id = 5;
  int64 created_at = 6;
}

message ErrorResult {
  uint32 code = 1;
  string message = 2;
}