tail -3f logfile.log | grep "action.*add" | sed -u -e "s/^/'/" -e "s/$/'/" | xargs -L 1 -P 5 bash testscript.sh

tail -3f logfile.log | grep "action.*add"

tail -3f /var/tmp/rabbitmq-tracing/logfile.log | grep "action.*add" | grep add

tail -f file.txt | grep something | grep something | grep something

{"twNotif": {"originator": "api", "chain": "test", "txId": "08640-0050568a5514", "version": "1.0", "msgType": "api", "twData": {"api": {"hostId": "007bdcc5", "user": "test", "cmdTxt": "100599"}}, "action": "add", "store": "test", "msgTime": 1467280648.971042}}

tail -3f logfile.log | grep --line-buffered "action.*add" | sed -u -e "s/^/'/" -e "s/$/'/" | xargs -L 1 -P 5 bash testscript.sh

... | stdbuf -oL grep ... | ...

tail -3f logfile.log | stdbuf -oL grep "action.*add" | sed -u -e "s/^/'/" -e "s/$/'/" | xargs -L 1 -P 5 bash testscript.sh

jq -c 'select(.twNotif.action == "add")' file.txt |
  xargs -d'n' -r -L 1 -P 5 ./testscript.sh

jq 'select(.twNotif.action == "add") | .twNotif.action' file.txt |
  sed -e 's/"//g' |
  xargs -d'n' -r -L 1 -P 5 ./testscript.sh

jsonpipe < file.txt |
  awk '$1 == "/twNotif/action" {gsub(/"/,""); print $2}' |
  xargs -d'n' -r -L 1 -P 5 ./testscript.sh

$ jsonpipe < file.txt
/   {}
/twNotif    {}
/twNotif/originator "api"
/twNotif/chain  "test"
/twNotif/txId   "08640-0050568a5514"
/twNotif/version    "1.0"
/twNotif/msgType    "api"
/twNotif/twData {}
/twNotif/twData/api {}
/twNotif/twData/api/hostId  "007bdcc5"
/twNotif/twData/api/user    "test"
/twNotif/twData/api/cmdTxt  "100599"
/twNotif/action "add"
/twNotif/store  "test"
/twNotif/msgTime    1467280648.971042

$ jsonpipe <file.txt | awk '{gsub(///,"."); print $1}'
.
.twNotif
.twNotif.originator
.twNotif.chain
.twNotif.txId
.twNotif.version
.twNotif.msgType
.twNotif.twData
.twNotif.twData.api
.twNotif.twData.api.hostId
.twNotif.twData.api.user
.twNotif.twData.api.cmdTxt
.twNotif.action
.twNotif.store
.twNotif.msgTime