Configuration

Config section key: tasks — loaded from tasks: in application.yaml or via LEX_TASKS__* environment variables.

tasks:
  enabled: true
  env: production
  backend:
    type: redis
    redis_url: "${REDIS_URL}"
    queue_name: orders
  worker:
    worker_count: 8
    poll_interval: 0.05
    default_timeout: 300
    enforce_timeout: true
  scheduler:
    enabled: true
    timezone: UTC
  rate_limit:
    enabled: true
    rate: 1000
    per: 1.0
  retry:
    max_retries: 5
    min_delay: 1.0
    max_delay: 300.0
  backends:
    - name: urgent
      primary: true
      type: redis
      redis_url: "${REDIS_URL}"
    - name: batch
      type: rabbitmq
      amqp_url: "${AMQP_URL}"

TaskConfig

Key	Type	Default	Env Var	Description
`name`	`str`	`"tasks"`	`LEX_TASKS__NAME`	Configuration name
`enabled`	`bool`	`True`	`LEX_TASKS__ENABLED`	Whether tasks module is enabled
`env`	`str \| None`	`None`	`LEX_TASKS__ENV`	Environment label (development/staging/production)
`backend`	`TaskBackendConfig`	`{}`	(prefix)	Task queue backend config
`worker`	`TaskWorkerConfig`	`{}`	(prefix)	Worker settings
`scheduler`	`TaskSchedulerConfig`	`{}`	(prefix)	Scheduler settings
`retry`	`RetryConfig`	`{}`	(prefix)	Retry policy
`rate_limit`	`TaskRateLimitConfig`	`{}`	(prefix)	Rate limiting
`timeout`	`TaskTimeoutConfig`	`{}`	(prefix)	Timeout settings
`extra`	`dict[str, Any]`	`{}`	`LEX_TASKS__EXTRA__*`	Extra arbitrary config
`backends`	`list[NamedTaskConfig]`	`[]`	(list)	Named multi-backend queues

TaskBackendConfig

Key	Type	Default	Env Var	Description
`type`	`str`	`"memory"`	`LEX_TASKS__BACKEND__TYPE`	Backend type: `memory`, `redis`, `rabbitmq`, `postgres`
`redis_url`	`SecretStr`	`"redis://localhost:6379"`	`LEX_TASKS__BACKEND__REDIS_URL`	Redis connection URL
`amqp_url`	`SecretStr`	`"amqp://localhost:5672/"`	`LEX_TASKS__BACKEND__AMQP_URL`	AMQP connection URL
`postgres_dsn`	`SecretStr \| None`	`None`	`LEX_TASKS__BACKEND__POSTGRES_DSN`	Postgres DSN (for `type: postgres`)
`queue_name`	`str`	`"tasks"`	`LEX_TASKS__BACKEND__QUEUE_NAME`	Queue name

TaskWorkerConfig

Key	Type	Default	Env Var	Description
`worker_count`	`int`	`1`	`LEX_TASKS__WORKER__WORKER_COUNT`	Number of worker instances
`max_concurrent_tasks`	`int`	`10`	`LEX_TASKS__WORKER__MAX_CONCURRENT_TASKS`	Max concurrent tasks per worker
`poll_interval`	`float`	`0.1`	`LEX_TASKS__WORKER__POLL_INTERVAL`	Queue poll interval (seconds)
`shutdown_timeout`	`float`	`30.0`	`LEX_TASKS__WORKER__SHUTDOWN_TIMEOUT`	Graceful shutdown timeout (seconds)
`default_timeout`	`float`	`300.0`	`LEX_TASKS__WORKER__DEFAULT_TIMEOUT`	Default task timeout (seconds)
`max_timeout`	`float`	`3600.0`	`LEX_TASKS__WORKER__MAX_TIMEOUT`	Maximum allowed timeout (seconds)
`enforce_timeout`	`bool`	`True`	`LEX_TASKS__WORKER__ENFORCE_TIMEOUT`	Enforce timeouts on all tasks

TaskSchedulerConfig

Key	Type	Default	Env Var	Description
`enabled`	`bool`	`True`	`LEX_TASKS__SCHEDULER__ENABLED`	Enable job scheduling
`check_interval`	`float`	`1.0`	`LEX_TASKS__SCHEDULER__CHECK_INTERVAL`	Schedule check interval (seconds)
`timezone`	`str`	`"UTC"`	`LEX_TASKS__SCHEDULER__TIMEZONE`	Timezone for cron expressions

TaskRateLimitConfig

Key	Type	Default	Env Var	Description
`enabled`	`bool`	`False`	`LEX_TASKS__RATE_LIMIT__ENABLED`	Enable rate limiting
`rate`	`int`	`100`	`LEX_TASKS__RATE_LIMIT__RATE`	Tasks allowed per time period
`per`	`float`	`1.0`	`LEX_TASKS__RATE_LIMIT__PER`	Time period (seconds)
`burst`	`int \| None`	`None`	`LEX_TASKS__RATE_LIMIT__BURST`	Max burst size

TaskTimeoutConfig

Key	Type	Default	Env Var	Description
`default_timeout`	`float`	`300.0`	`LEX_TASKS__TIMEOUT__DEFAULT_TIMEOUT`	Default task timeout
`max_timeout`	`float`	`3600.0`	`LEX_TASKS__TIMEOUT__MAX_TIMEOUT`	Maximum allowed timeout
`enforce_timeout`	`bool`	`True`	`LEX_TASKS__TIMEOUT__ENFORCE_TIMEOUT`	Enforce timeouts

NamedTaskConfig

Used in TaskConfig.backends for multi-backend queues.

Key	Type	Default	Description
`name`	`str`	(required)	Unique backend name for `Named()` DI resolution
`primary`	`bool`	`False`	Also register under unnamed `TaskQueueProtocol`
`type`	`str`	`"memory"`	Backend type: `memory`, `redis`, `rabbitmq`, `postgres`
`redis_url`	`SecretStr \| None`	`None`	Redis URL (when `type: redis`)
`amqp_url`	`SecretStr \| None`	`None`	AMQP URL (when `type: rabbitmq`)
`postgres_dsn`	`SecretStr \| None`	`None`	Postgres DSN (when `type: postgres`)
`queue_name`	`str`	`"tasks"`	Queue name for this backend

Environment Variable Overrides

Nested keys use __ as delimiter:

# Set Redis backend URL
export LEX_TASKS__BACKEND__REDIS_URL="redis://prod-cluster:6379"

# Set worker count
export LEX_TASKS__WORKER__WORKER_COUNT=16

# Disable scheduler
export LEX_TASKS__SCHEDULER__ENABLED=false

# Set production environment
export LEX_TASKS__ENV=production