[SOLVED] PredictionIO training engine fails with error

PredictionIO training engine fails with error - WorkflowConfig is empty. Quitting

I'm trying to deploy an engine. I'm following the docs. So I:

create the app,
download the engine,
update the app name in engine.json,
build it: pio build --verbose,
then train: pio train --verbose.

Everything works, building completes successfully. However, training always fails with error:

[ERROR] [CreateWorkflow$] WorkflowConfig is empty. Quitting

I tried downloading another engine but the error is the same. There is nothing on the Internet about the WorkflowConfig. Does anyone have a clue what might be wrong?

I'm attaching pio.log contents below.

2015-07-07 07:20:06,128 INFO  io.prediction.tools.console.Console$ [main] - Using existing engine manifest JSON at /home/vagrant/PredictionIO/mubuzz-similar-articles/manifest.json
2015-07-07 07:20:06,875 INFO  org.elasticsearch.plugins [main] - [Jude the Entropic Man] loaded [], sites []
2015-07-07 07:20:07,706 INFO  io.prediction.tools.Runner$ [main] - Submission command: /home/vagrant/PredictionIO/vendors/spark-1.3.1/bin/spark-submit --class io.prediction.workflow.CreateWorkflow --jars file:/home/vagrant/PredictionIO/mubuzz-similar-articles/target/scala-2.10/template-scala-parallel-similarproduct_2.10-0.1-SNAPSHOT.jar,file:/home/vagrant/PredictionIO/mubuzz-similar-articles/target/scala-2.10/template-scala-parallel-similarproduct-assembly-0.1-SNAPSHOT-deps.jar --files file:/home/vagrant/PredictionIO/conf/log4j.properties,file:/home/vagrant/PredictionIO/vendors/hbase-1.0.0/conf/hbase-site.xml --driver-class-path /home/vagrant/PredictionIO/conf:/home/vagrant/PredictionIO/vendors/hbase-1.0.0/conf file:/home/vagrant/PredictionIO/lib/pio-assembly-0.9.3.jar --engine-id sZTyLTTx277Kv58cgSQub4igE60DDagR --engine-version e7c5e07b70df531e8f7a92d278a16278c56d0581 --engine-variant file:/home/vagrant/PredictionIO/mubuzz-similar-articles/engine.json --verbosity 0 --verbose --json-extractor Both --env PIO_STORAGE_SOURCES_HBASE_TYPE=hbase,PIO_ENV_LOADED=1,PIO_STORAGE_REPOSITORIES_METADATA_NAME=pio_meta,PIO_FS_BASEDIR=/home/vagrant/.pio_store,PIO_STORAGE_SOURCES_HBASE_HOME=/home/vagrant/PredictionIO/vendors/hbase-1.0.0,PIO_HOME=/home/vagrant/PredictionIO,PIO_FS_ENGINESDIR=/home/vagrant/.pio_store/engines,PIO_STORAGE_SOURCES_LOCALFS_PATH=/home/vagrant/.pio_store/models,PIO_STORAGE_SOURCES_ELASTICSEARCH_TYPE=elasticsearch,PIO_STORAGE_REPOSITORIES_METADATA_SOURCE=ELASTICSEARCH,PIO_STORAGE_REPOSITORIES_MODELDATA_SOURCE=LOCALFS,PIO_STORAGE_REPOSITORIES_EVENTDATA_NAME=pio_event,PIO_STORAGE_SOURCES_ELASTICSEARCH_HOME=/home/vagrant/PredictionIO/vendors/elasticsearch-1.4.4,PIO_FS_TMPDIR=/home/vagrant/.pio_store/tmp,PIO_STORAGE_REPOSITORIES_MODELDATA_NAME=pio_model,PIO_STORAGE_REPOSITORIES_EVENTDATA_SOURCE=HBASE,PIO_CONF_DIR=/home/vagrant/PredictionIO/conf,PIO_STORAGE_SOURCES_LOCALFS_TYPE=localfs --verbose
2015-07-07 07:20:08,903 ERROR io.prediction.workflow.CreateWorkflow$ [main] - WorkflowConfig is empty. Quitting

Solution

This is a known issue, and fixed in the next release. See the JIRA ticket, here: https://predictionio.atlassian.net/browse/PDIO-636

You just need to omit --verbose for now.