I *think* the issue is that NiFi is using the exception for logical flow
and that it falls into the logging so to speak, as a side effect.

From: Fabian Reiber <[email protected]> <[email protected]>
Reply: [email protected] <[email protected]> <[email protected]>
Date: January 4, 2023 at 11:01:05
To: [email protected] <[email protected]> <[email protected]>
Subject:  Re: Unintelligible exception log for HTTP-200 response

Thanks Otto for your response.

Indeed this is the exception which is thrown. We activated the debug
br/>logging and saw that there is no flow file to transfer: <

2023-01-04 15:48:53,701 DEBUG [NiFi Web Server-6778]
brr/>o.a.nifi.web.api.DataTransferResource finished transferring flow
files, br/>numOfFFlowFiles=0

After this log, and few other debug logs, the raised exception is logged.

I am not sure what it means as well. Why must NiFi throw an exception,
br/>if no data is available to transfer?? According to my understanding, it
br/>is not an exception, if no data exists to transffer.

Do someone knows more about the behaviour there? :-)

Kind regards
Fabian

Am 04.01.23 um 14:16 schrieb Otto Fowler:
> ```
> try {
> int numOfFlowFiles =
> serverProtocol.getPort().transferFlowFiles(peer, serverProtocol);
> logger.debug("finished transferring flow files,
> numOfFlowFiles={}", numOfFlowFiles);
> if (numOfFlowFiles < 1) {
> // There was no flow file to transfer. Throw
> this exception to stop responding with SEE OTHER.
> throw new
> WebApplicationException(Response.Status.OK);
> }
> } catch (NotAuthorizedException | BadRequestException |
> RequestExpiredException e) {
> // Handshake is done outside of write() method, so
> these exception wouldn't be thrown.
> throw new IOException("Failed to process the
> request.", e);
> }
> ```
>
> I’m not sure about what this means, other than what it says, that there
is
> nothing to transfer
>
> From: Fabian Reiber <[email protected]> <[email protected]>
> Reply: [email protected] <[email protected]> <
[email protected]>
> Date: January 3, 2023 at 10:24:54
> To: [email protected] <[email protected]> <[email protected]>
> Subject: Unintelligible exception log for HTTP-200 response
>
> Hi people,
>
> We have a setup with 2 NiFi instances (here we name it "nifi-instance-1"
> br/>and ""nifi-instance-2") in version 1.16.3 running in podman
containers
> br/>respectively in pods. In the log file of nifi-app.log we discover the
> br/>following: <
>
> 2023-01-03 12:00:00,195 INFO [NiFi Web Server-46]
> br//>org.apache.nifi.web.server.RequestLog 10.0.2.100 - nifi-instance-2
> [03/Jan/2023:12:00:00 +0000] "POST
>
br/>/nifi-api/data-trannsfer/output-ports/721c54f7-0185-1000-8cc8-d1a327e7a98f/transactions

>
> HTTP/1.1" 201 155 "-" "Apache-HttpClient/4.5.13 (Java/11.0.12)"
> br/>2023-01-03 12:00:00,221 WARN [[NiFi Web Server-235]
> o.a.n.w.a.c.WebApplicationExceptionMapper
> br/>javax.ws.rs.WebAppplicationException: HTTP 200 OK. Returning 200
> br/>response. javax.wss.rs.WebApplicationException: HTTP 200 OK at
>
br/>org.apache.nifi.web..api.DataTransferResource$1.write(DataTransferResource.java:670)

> brr/>at
>
br/>org.glassfish.jersey.message.internal.StreamingOutputProvidder.writeTo(StreamingOutputProvider.java:55)

>
> ...
> at
>
br/>org.eclipse.jetty.util.thread.QueuuedThreadPool.runJob(QueuedThreadPool.java:883)

>
> at
>
br/>org.eclipse.jetty.util.thread.QueuuedThreadPool$Runner.run(QueuedThreadPool.java:1034)

>
> at java.base/java.lang.Thread.run(Unknown Source)
>
>
> The full traceback is attached. The instances are running on the same
> br/>machine and working properly. ""nifi-instance-1" has an output port
> br/>configured as ""Remote connections (site-to-site)". "nifi-instance-2"
> has br/>a Remote Process Group and is configuured to connect to br/>""
> nifi-instance-1.de" via HTTPs to fetch the flow files. The connection
> br/>between them and the sharing of floow files work as expected. Except
> this br/>log message we don't underrstand.
>
> The authorizations.xml of "nifi-instance-1" has this configuration,
> br/>among other things, to allow the other instance to send/reeceive
data:
>
> <policy identifier="cbeec38a-0178-1000-77da-25e37ce5344e"
>
br/>resource="/data-transfer/output-ports/721c54f7-0185-1000-8cc8-d1a327e7a98f"

> br/>action="W">
> <group identifier="1f68ef93-0176-1000-c949-f005799da72d"/>
> </policy>
> <policy identifier="2fe2ee5f-0174-1000-e61b-45137c67eac1"
> br/>resource="/site-to-site" action="R">
> <group identifier="1f68ef93-0176-1000-c949-f005799da72d"/>
> </policy>
>
> The users.xml contains among other things this:
>
> <group identifier="1f68ef93-0176-1000-c949-f005799da72d"
> br/>name="nifi-instance-2">
> <user identifier="1f6ba22e-0176-1000-7b45-ec3ea6d38fe5"/>
> </group>
> <users>
> <user identifier="1f6ba22e-0176-1000-7b45-ec3ea6d38fe5" br/>identity="
> nifi-instance-2.de"/>
> </users>
>
> "nifi-instance-2" has also the configuration for the /site-to-site
> br/>resource to allow it for ""nifi-instance-1". But it should not be
> br/>necessary for the occurrence of this log. <
>
> As I said, the data exchange between them is working fine. We found this
> br/>issue: https://issues.apache.org/jira/browse/NIFFI-9752 and already
> br/>deleted and recreated the output port, but without ssuccess.
>
> The last output in the stack trace hypothesizes that there is something
> br/>wrong with the permissions!!? But we are not sure. Do we miss
anything?
>
> Do you have any idea what the reason could be for this log? We guess, we
> br/>can suppress the log in our logback config. But we wantt to figure
out
> br/>what the reason is :-) <
>
> Kind regards
> Fabian
>
> -- br/>FFabian Reiber, M.Sc. (Projekt- u. Entwicklungsteam)
> Phone: +49 40 808077-689 Fax: +49 40 808077-556 Mail: [email protected]
>
> DFN-CERT Services GmbH, https://www.dfn-cert.de/, Phone +49 40 808077-555
> Sitz / Register: Hamburg, AG Hamburg, HRB 88805, Ust-IdNr.: DE 232129737
> Nagelsweg 41, 20097 Hamburg, Germany. CEO: Dr. Klaus-Peter Kossakowski
>

-- br/>FFabian Reiber, M.Sc. (Projekt- u. Entwicklungsteam)
Phone: +49 40 808077-689 Fax: +49 40 808077-556 Mail: [email protected]

DFN-CERT Services GmbH, https://www.dfn-cert.de/, Phone +49 40 808077-555
Sitz / Register: Hamburg, AG Hamburg, HRB 88805, Ust-IdNr.: DE 232129737
Nagelsweg 41, 20097 Hamburg, Germany. CEO: Dr. Klaus-Peter Kossakowski

Reply via email to