IMO... UpdateAttribute has been around since the beginning of time, I can't see adding a failure relationship. At the same time I understand the want for such exceptions to be handled more gracefully rather than rolling back indefinitely. I'd vote in favor of considering Moser's option #2... and being able to implement an "if this then that" logic within your flow.
Also just thinking... for every UA failure you have to consider a good failure-management strategy, which MIGHT add a lot of noise to the flow. Something that might otherwise easily be identified in a downstream component and/or database/etc. My 2 cents ** Phil On Wed, Feb 7, 2024 at 5:18 PM Adam Taft <a...@adamtaft.com> wrote: > Or better, the failure relationship just doesn't even exist until the > property "Has Failure Relationship" is set to True. This involves updating > UpdateAttribute to have dynamic relationships (the failure relationships > appearing on true), which isn't hard to do in processor code. > > This has the advantage of being backwards compatible for existing users and > allows the failure relationship to exist for new configurations. Obviously > the processor would need an update to catch Expression Language exceptions > and then route conditionally to failure. > > Just thinking out loud. > /Adam > > > > On Wed, Feb 7, 2024 at 1:48 PM u...@moosheimer.com <u...@moosheimer.com> > wrote: > > > Hi Mike, > > > > How about the option of introducing a new property that decides whether > to > > route to the 'failure' relationship in the event of an error? > > If this property is set to false, then the 'failure' relationship is > > automatically set to 'terminate' (since nothing is routed there anyway). > > > > Then everyone can decide whether and where they want to use this new > > feature or not. > > All other options would still be possible with such a solution. > > > > -- Uwe > > > > > Am 07.02.2024 um 22:15 schrieb Michael Moser <moser...@gmail.com>: > > > > > > Hi Dan, > > > > > > This has been discussed in the past, as you found with those two Jira > > > tickets. Personally, I'm still not sure whether a new failure > > relationship > > > on UpdateAttribute in 2.0 is a good approach. I have heard from some > > > dataflow managers that would not want to go through their entire graph > > when > > > upgrading to 2.0 and update every UpdateAttribute configuration. > > > > > > I have heard some alternatives to a 'failure' relationship that I would > > > like to share as options. > > > > > > 1) Add a new property to UpdateAttribute that controls whether a > flowfile > > > that causes an expression language exception either yields and rolls > > back, > > > or silently fails to update the attribute and sends the flowfile to > > > success. I personally don't like this, because the use case for > "silent > > > failure" seems really like a rarely needed edge case. > > > > > > 2) Identify all expression language methods that can throw an exception > > and > > > document that fact in the Expression Language Guide (some methods > already > > > mention they can throw an "exception bulletin"). Then implement new > > > expression methods to check if an expression could fail, and use that > in > > > UpdateAttribute advanced rules. For example, if the format() and > > > formatInstant() methods can fail on a negative number, we create a new > > > method such as isValidMilliseconds(). This already exists for some > > cases, > > > such as isJson() which can do a quick check of some value before > calling > > > jsonPathDelete() on it. > > > > > > I'm curious to hear more thoughts on this. > > > > > > -- Mike > > > > > > > > > > > >> On Wed, Jan 31, 2024 at 11:02 AM Dan S <dsti...@gmail.com> wrote: > > >> > > >> My team is requesting a failure relationship for UpdateAttribute as > > seen in > > >> NIFI-5448 <https://issues.apache.org/jira/browse/NIFI-5448> and > > NIFI-6344 > > >> <https://issues.apache.org/jira/browse/NIFI-6344> as we are > > >> experiencing the same problem where a NIFI Expression Language is > > throwing > > >> an exception. In the PR for NIFI-5448 it was mentioned this feature > > would > > >> have to wait until NIFI 2.0.0. I wanted to know if there is any active > > work > > >> regarding this and whether eventually there will be a failure > > relationship > > >> added to UpdateAttribute? > > >> > > > > >
