safely.thread-pool — com.brunobonacci/safely 0.7.0-alpha3

async-execute-with-pool clj

(async-execute-with-pool pool thunk)

It returns a promise which will deliver tuple of 3 values where the first value is a the result of the execution of the thunk. The second value is nil when the execution is successful or :error if the thunk throws an exception, and :queue-full when the thread pool can't accent any more tasks.

cancel clj

(cancel task & {:keys [force] :or {force false}})

Attempts to cancel execution of this task. This attempt will fail if the task has already completed, has already been cancelled, or could not be cancelled for some other reason. If successful, and this task has not started when cancel is called, this task should never run. If the task has already started, then the :force true parameter determines whether the thread executing this task should be interrupted in an attempt to stop the task.

Returns false if the task could not be cancelled, typically because it has already completed normally; true if the cancellation was requested and nil if the task was not cancellable.

execute-with-pool clj

(execute-with-pool pool
                   timeout
                   thunk
                   &
                   {:keys [cancel-on-timeout] :or {cancel-on-timeout :always}})

It returns a promise which will deliver tuple of 3 values where the first value is a the result of the execution of the thunk. The second value is nil when the execution is successful or :error if the thunk throws an exception,:queue-full when the thread pool can't accent any more tasks, and :timeout when a timeout was reached.

fixed-thread-pool clj

(fixed-thread-pool name size & {:keys [queue-size] :as opts})

running-task-count clj

(running-task-count tp)

Returns the approximate count of in flight tasks

thread clj macro

(thread & body)

(thread name & body)

(thread {:keys [name daemon priority auto-start]} & body)

It creates a thread and run the give thunk in the new thread. It returns a promise of a result, it's similar to a future, but you can control the thread name, priority etc. If auto-start is true then the thread is started after its creation; if false then instead of returning a promise with the result it return a function with no arguments which when called it starts the thread and return the promise. All exception are caught and returned as result.

examples:

;; create and starts a thread named `runner`
(thread "runner"
    (println "Hi from runner!"))
;;=> nil

;; create and starts a thread named `runner` and get the result
@(thread {:name "runner"}
    (reduce + (range 1000)))
;;=> 499500

;; create and starts a thread named `runner`
(def t
  (thread {:name "runner" :auto-start false}
      (reduce + (range 1000))))
;; call the function to start the thread, deref for the result
@(t)
;;=> 499500

;; exceptions are returned as result
@(thread "bad-runner"
    (/ 1 0))
;; it captures and returns the exception
;;=> java.lang.ArithmeticException("Divide by zero")

thread* clj

(thread* {:keys [name daemon priority auto-start]
          :or {name "safely-custom-thread" daemon false auto-start true}}
         thunk)

It creates a thread and run the give thunk in the new thread. It returns a promise of a result, it's similar to a future, but you can control the thread name, priority etc. If auto-start is true then the thread is started after its creation; if false then instead of returning a promise with the result it return a function with no arguments which when called it starts the thread and return the promise. All exception are caught and returned as result.

examples:

;; create and starts a thread named `runner`
(thread* {:name "runner"}
  (fn []
    (println "Hi from runner!")))
;;=> nil

;; create and starts a thread named `runner` and get the result
@(thread* {:name "runner"}
  (fn []
    (reduce + (range 1000))))
;;=> 499500

;; create and starts a thread named `runner`
(def t
  (thread* {:name "runner" :auto-start false}
    (fn []
      (reduce + (range 1000)))))
;; call the function to start the thread, deref for the result
@(t)
;;=> 499500

;; exceptions are returned as result
@(thread* {:name "bad-runner"}
  (fn []
    (/ 1 0)))
;; it capture and returns the exception
;;=> java.lang.ArithmeticException("Divide by zero")

thread-factory clj

(thread-factory prefix daemon uncaught-exception-handler)

Creates a thread factory which creates threads with the given prefix and a incremental counter. The threads can be created as daemon.

thread-pool clj

(thread-pool {:keys [name core-size max-size keep-alive-time queue-size]
              :or {name "safely.unnamed"
                   core-size 5
                   max-size 10
                   keep-alive-time 60000
                   queue-size 50}})

Creates a thread pool.

timeout-wait clj

(timeout-wait value timeout cancel-strategy)

It waits on a async value up to a given timeout. If the timeout is elapsed and the value is not available yet, then then the task is cancelled according to the cancel-strategy. accepted values: :never, :if-not-running or :always