Constant for a done job state.

Constant for a failed job state.

Constant for a new job state.

Creates Byplay’s table and other stuff in the database (if it doesn’t already exist).

Creates several threads for infinitely calling work-once in them with the specified polling interval. Returns a WorkerProtocol instance which can be started when needed.

dbspec specifies the database connection parameters and has the same format as in funcool/clojure.jdbc.

Config keys:

• :queues - vector of queues to poll (order matters), default is nil which means that worker can take a job from any queue
• :threads-num - number of worker threads, default is 1
• :polling-interval - in msec, default is 5000
• :on-fail - a function with signature (on-fail worker exception job-row-map) executed on exception inside a job, by default it prints a message into stderr
• :on-ack - a function (on-ack worker ack) will be executed in child threads with the result of every work-once call. By default does nothing and is mostly useful for testing. If on-fail is specified then in case of a failed job on-ack will be executed after on-fail. You can (.interrupt (Thread/currentThread)) in on-ack to stop working in the particular child thread.

Converts the queue name from a Clojure keyword into a string for SQL. The keyword must not have a namespace.

Converts the queue name from a string into a Clojure keyword.

Removes all Byplay data from the database (if there’s any).

Puts the job into the queue specified in the job’s metadata at ::queue. If no queue is specified then job will be scheduled to :default queue.

Puts the job into the specified queue. If nil queue is specified then job will be scheduled to :default queue.

Low-level API. Processes a single job from one of the queues. The order of the queues matters. If no queues are specified than a job from any queue will be taken.

Returns an ack:

• nil - if job was not found
• job row map - if job is done, e.g. {:id 123 :state job-state-done :job "app.jobs/some-job" :args "(1 2)" :queue :some-queue}
• [exception, job row map] - if job has failed

Job exception is not rethrown but the job is marked failed instead of done.

Do not call this function inside an already created transaction because work-once will create a new transaction itself. Otherwise, your outer transaction will be prematurely committed because nested transactions are not supported by PostgreSQL.