backup mongodb using BareOS' bpipe plugin

mongo_bpipe.sh

#!/bin/sh

# Save this file on the on FD
# /usr/lib/bareos/plugins/mongo_bpipe.sh

#DBNAMES=""
#DBUSERNAME=""
#DBPASSWORD=""
#DBAUTHDB=""

OPT="--quiet"
if [ "$DBUSERNAME" ]; then
  OPT="$OPT --username=$DBUSERNAME --password=$DBPASSWORD"
  if [ "$DBAUTHDB" ]; then
    OPT="$OPT --authenticationDatabase=$DBAUTHDB"
  fi
fi

if [ -z "$DBNAMES" ]; then
  DBNAMES=$(echo "show dbs" | mongo $OPT | awk '{list=list " " $1} END {print list}')
fi

for db in $DBNAMES; do
  if [ "$db" != "admin" ] && [ "$db" != "config" ] && [ "$db" != "local" ]; then
    for coll in $(mongo $OPT $db --eval "db.getCollectionNames()"| grep \"| awk -F\" '{list=list " " $2} END {print list}'); do
      echo "bpipe:/_mongobackups_/$db/$coll.bson:mongodump $OPT --db $db --collection $coll -o -:mongorestore $OPT --db $db --collection $coll -"
    done
  fi
done

mongodb.conf

# /etc/bareos/bareos-dir.d/fileset/mongodb.conf
FileSet {
    Name = "mongodb"
    Include {
      Options {
        signature = MD5
        compression = lz4
      }
      Plugin = "\\|/usr/lib/bareos/plugins/mongo_bpipe.sh %l"
    }
}

myself.conf

# /etc/bareos/bareos-fd.d/client/myself.conf
Client {
  ...
  # Load bpipe plugin
  Plugin Names = "bpipe"
  ...

}

Hello, actually I have the next error on bareos saying:
Fatal error: bpipe-fd: Error closing stream for pseudo file /_mongobackups_/.....

Was trying to find a solution but nothing about bpipe. This is the bpipe code and it prints the error on IO error:
https://fossies.org/linux/bareos/core/src/plugins/filed/bpipe/bpipe-fd.cc

Using Bareos-fd 20.0.1