Database

lilota executes tasks in a managed way. All information processed by lilota is stored in various database tables in order to make it transparent to the user what is happening in the system.

Tables

Node (lilota_node)

This table stores information about the scheduler responsible for scheduling tasks in the system, as well as the workers responsible for executing them.

Column	Description
id	Unique identifier of the node (UUID).
name	Optional human-readable name of the node.
type	Type of node (scheduler or worker).
status	Current lifecycle status of the node (e.g., starting, running, stopped, dead).
created_at	Timestamp when the node record was created.
last_seen_at	Timestamp of the most recent heartbeat received from the node. Used to detect stale or dead nodes.

NodeLeader (lilota_node_leader)

This table stores information about the worker that currently acts as the leader.

Column	Description
id	Primary key for the leader record (typically a single-row table).
node_id	Identifier of the node currently acting as the cluster leader.
lease_expires_at	Timestamp indicating when the leader lease expires if not renewed.

Task (lilota_task)

This table stores information about the tasks executed by the system.

Column	Description
id	Unique identifier of the task (UUID).
name	Name of the registered task function to execute.
pid	Process identifier associated with the task execution.
status	Current status of the task (created, scheduled, running, completed, failed, cancelled).
run_at	Timestamp indicating when the task becomes eligible for execution.
attempts	Number of execution attempts made for this task.
max_attempts	Maximum allowed retry attempts before the task is marked as failed.
timeout	Maximum execution duration allowed for the task before it should be considered timed out.
expires_at	Optional timestamp (UTC) after which the task is considered expired and should no longer be executed.
progress_percentage	Current progress of the task expressed as a percentage (0–100).
start_date_time	Timestamp when the task started execution.
end_date_time	Timestamp when the task finished execution (successfully or with failure).
input	JSON payload containing the input parameters for the task.
output	JSON payload containing the result produced by the task.
error	JSON object describing an error if the task execution failed.
locked_by	Identifier of the worker node currently holding the execution lock for the task.
locked_at	Timestamp when the task was locked by a worker for execution.

LogEntry (lilota_log)

lilota supports logging and stores all log messages in this table.

Column	Description
id	Unique identifier of the log entry.
created_at	Timestamp when the log message was created.
level	Logging level (e.g., DEBUG, INFO, WARNING, ERROR).
logger	Name of the logger that produced the message.
message	Log message text.
process	Identifier of the process that produced the log entry.
thread	Identifier of the thread that produced the log entry.
node_id	Optional reference to the node associated with the log entry.
task_id	Optional reference to the task associated with the log entry.