rally_runtime/system

System database: observability and background jobs.

Opens a separate SQLite database (system.db) for message logging and the job queue. The connection is stored globally so any WS handler process can log messages. Uses synchronous=OFF because losing a few recent log entries on crash is acceptable for the throughput gain.

Types

JobHandler

</>

pub type JobHandler =
  fn(String, BitArray) -> Result(Nil, String)

Values

enqueue

</>

pub fn enqueue(
  name name: String,
  payload payload: BitArray,
  run_at run_at: Int,
) -> Nil

Enqueue a job to run at a specific time.

enqueue_in

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pub fn enqueue_in(
  name name: String,
  payload payload: BitArray,
  delay_seconds delay_seconds: Int,
) -> Nil

Enqueue a job to run after a delay.

enqueue_now

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pub fn enqueue_now(
  name name: String,
  payload payload: BitArray,
) -> Nil

Enqueue a job to run immediately.

start

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pub fn start(path: String) -> Nil

Call during app startup. Opens the system DB and stores the connection globally so any process (WS handlers) can access it.

start_with_jobs

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pub fn start_with_jobs(
  path path: String,
  handler handler: fn(String, BitArray) -> Result(Nil, String),
) -> Nil

Start the system DB with a background job runner.