Hi, I’m trying to write an eventing function that calls a REST endpoint in an exponential backoff manner. Is there a way to do this please?
The Eventing documentation is here - Eventing Service: Fundamentals | Couchbase Docs
The Eventing Examples documentation is here - Examples: Using the Eventing Service | Couchbase Docs
There is advice on making REST calls here - javascript rest call - Google Search
And retrying with exponential backoff in javascript here - rest call exponential backoff javascript - Google Search
thank you, saw all of them, is there no way to define or use async in the eventing service?
The first link looks promising.
https://docs.couchbase.com › server › current › eventing
Timers are asynchronous compute, which offers Eventing Functions the ability to execute in reference to wall-clock events, refer to the detailed Timers …
Thanks again, looks like I can’t use async functions at top-level. I’ll figure a way around this, but I’m running into a different issue now. I’m making a REST call, but it’s failing. I’m seeing no logs for it though to further understand the issue. How do I log curl requests within the eventing script please?
By the way, setTimeout is not being recognized and throwing a reference error. Is there an alternative way of leveraging this method within the Eventing script?
logging: Language Constructs | Couchbase Docs
So your function will need to capture the message and log it as shown. There is a “Log” link in the UI to display the logged messages. When creating the function, under Settings, there is a System Log Level.
setTimeout is not being recognized
Yes. The sample in the documentation says:
setTimeout(function(){}, 300); // Not allowed - asynchronous flow.
and
Limited asynchrony is added back through time observers (or Timers).
Here is the sample for creating a timer function.
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Here is a great blog talking about how to create a “dead letter queue” … I would not always spin up timers for the cURL… I would try the curl 2-3 time 10 seconds apart and if it fails spin up a CouchBase Eventing Timer to retry the cURL ever XYZ minutes.
Sorry for the delay in responding here - swamped with work.
I managed to get this done via timers themselves managed via traditional looping constructs 
Sadly the JS runtime in Eventing is very restricted and isn’t allowing some async constructs.
Marked @mreiche 's describing timers as asynchronous compute actually triggered me to think of them as a potential solution
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