AWS Simple Workflow Service (SWF): Gotchas

After spending a whole day debugging task lists routing and coordination; I realized that the reason I kept getting errors was:

  • task/activity registration parameters (e.g. defaultTaskList) are immutable.

Once I realized this, the fix was extremely simple — change activities version to force the new types.

In part, this issue could be alleviated by enabling log4j; you need to create src/main/resources.log4.prorperties:

# Set root logger level to DEBUG and its only appender to A1.
log4j.rootLogger=INFO, A1

# A1 is set to be a ConsoleAppender.

# A1 uses PatternLayout.
log4j.appender.A1.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n








keywords (search bread crumbs):

amazon work flow


After spending several days debugging task routing; I finally stumbled upon this post — which made me realize that the reason that I wasn’t able to get the task routing working was the immutability of activity registration parameters.

Would it be possible to add an exception if there is an attempt to overwrite the immutable registration parameters? I have submitted this issue to the aws-sdk github.

I think mentioning immutability in the SWF docs would be quite beneficial as well.

p.s. I greatly enjoy using SWF; am surprised that it is not as widely used (or promoted) yet 
(am working on converting my colleagues)

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About Neil Rubens

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