webMethods Knowlegebase : com.google.protobuf.InvalidProtocolBufferException: Protocol message contained an invalid tag (zero) (1790435)

Problem

User has IS test package with a doctype with a structured field name having periods (BatchTransfer.doc.config). The doctype is synched to UM with property: Encoding type=Protocol buffers.

When publishing a doc event with only the root elements works. But if you populate the BatchTransfer.doc.config element and publish, you get an infinite loop in the IS server log:

Example:

2018-05-03 08:57:43 CEST [ISS.0153.0089C] Trigger test:tempTrigger failed decoding: com.wm.app.b2b.server.dispatcher.exceptions.MessagingCoderException: java.io.IOException: com.google.protobuf.InvalidProtocolBufferException: Protocol message contained an invalid tag (zero).

2018-05-03 08:57:43 CEST [ISS.0153.0046I] Trigger test:tempTrigger has recovered the message(s).

2018-05-03 08:57:43 CEST [ISS.0153.0089C] Trigger test:tempTrigger failed decoding: com.wm.app.b2b.server.dispatcher.exceptions.MessagingCoderException: java.io.IOException: com.google.protobuf.InvalidProtocolBufferException: Protocol message contained an invalid tag (zero).

2018-05-03 08:57:43 CEST [ISS.0153.0046I] Trigger test:tempTrigger has recovered the message(s).

2018-05-03 08:57:43 CEST [ISS.0153.0089C] Trigger test:tempTrigger failed decoding: com.wm.app.b2b.server.dispatcher.exceptions.MessagingCoderException: java.io.IOException: com.google.protobuf.InvalidProtocolBufferException: Protocol message contained an invalid tag (zero).

2018-05-03 08:57:43 CEST [ISS.0153.0046I] Trigger test:tempTrigger has recovered the message(s).

The client will keep trying to consume the same message, fail, and then try again. In UM, you see 1 Published, and a rapidly rising number for Consumed until you purge the channel.