topic Re: Using Thread.sleep in Scala in Data Engineering

Using Thread.sleep in Scala

Sunny — Fri, 17 Jun 2022 12:04:18 GMT

We need to hit REST web service every 5 mins until success message is received. The Scala object is inside a Jar file and gets invoked by Databricks task within a workflow.

Thread.sleep(5000)

is working fine but not sure if it is safe practice or is there any alternates.

Currently I have this implementation

while (true) {

// hit the rest web service

if(response == "success")

return;

Thread.sleep(300000)

}

Re: Using Thread.sleep in Scala

ron_defreitas — Wed, 29 Jun 2022 19:24:15 GMT

Nothing wrong with using Sleep per se, but this business logic lacks timeout logic.

If it never returns success, your job will run forever, consuming DBUs as well as cloud compute costs.

Using the scala concurrent duration classes, you can create a deadline, then write your code to incorporate that.

while (deadline.hasTimeLeft()) {

// your break logic

// sleep

}

Re: Using Thread.sleep in Scala

ron_defreitas — Wed, 29 Jun 2022 19:26:20 GMT

I'll add that you may wish to hit the endpoint more frequently if your web service can take it... it's wasteful to poll once every five minutes for a response that might return at 5 minutes and 1 second.

Re: Using Thread.sleep in Scala

angrypanda — Wed, 29 Jun 2022 20:09:00 GMT

Have you tried using Scala Futures?

Re: Using Thread.sleep in Scala

ron_defreitas — Wed, 29 Jun 2022 20:33:35 GMT

Sounds like this is an instance of needing a synchronous blocking call, so a future wouldn't help the OP

Re: Using Thread.sleep in Scala

Sunny — Thu, 30 Jun 2022 12:06:06 GMT

Thank you. For ex, if the job has a timeout set to 15 mins and the code has while(true), after 15 mins isn't the job killed automatically?

Re: Using Thread.sleep in Scala

Vartika — Wed, 24 Aug 2022 16:18:18 GMT

Hey there @Sundeep P

Hope all is well!

Just wanted to check in if you were able to resolve your issue and would you be happy to share the solution or mark an answer as best? Else please let us know if you need more help.

We'd love to hear from you.

Cheers!