Backport tail sooner enhancement

Author: rjeberhard

operator/src/main/resources/scripts/startServer.sh

@@ -64,6 +64,17 @@ function startWLS() {
 
  traceTiming "POD '${SERVICE_NAME}' MD5 END"
 
+ #
+ # We "tail" the future WL Server .out file to stdout in background _before_ starting
+ # the WLS Server because we use WLST 'nmStart()' to start the server and nmStart doesn't return
+ # control until WLS reaches the RUNNING state.
+ #
+
+ if [ "${SERVER_OUT_IN_POD_LOG}" == 'true' ] ; then
+ trace "Showing the server out file from ${SERVER_OUT_FILE}"
+ ${SCRIPTPATH}/tailLog.sh ${SERVER_OUT_FILE} ${SERVER_PID_FILE} &
+ fi
+
  #
  # Start WL Server
  #
@@ -76,6 +87,12 @@ function startWLS() {
  ${SCRIPTPATH}/wlst.sh $SCRIPTPATH/start-server.py
 
  traceTiming "POD '${SERVICE_NAME}' WLS STARTED"
+
+ FAIL_BOOT_ON_SITUATIONAL_CONFIG_ERROR=${FAIL_BOOT_ON_SITUATIONAL_CONFIG_ERROR:-true}
+ SERVER_OUT_MONITOR_INTERVAL=${SERVER_OUT_MONITOR_INTERVAL:-3}
+ if [ ${FAIL_BOOT_ON_SITUATIONAL_CONFIG_ERROR} == 'true' ] ; then
+ ${SCRIPTPATH}/monitorLog.sh ${SERVER_OUT_FILE} ${SERVER_OUT_MONITOR_INTERVAL} &
+ fi
 }
 
 function mockWLS() {
@@ -89,22 +106,6 @@ function mockWLS() {
  echo "RUNNING:Y:N" > $STATEFILE
 }
 
-function waitUntilShutdown() {
- #
- # Wait forever. Kubernetes will monitor this pod via liveness and readyness probes.
- #
- if [ "${SERVER_OUT_IN_POD_LOG}" == 'true' ] ; then
- trace "Showing the server out file from ${SERVER_OUT_FILE}"
- ${SCRIPTPATH}/tailLog.sh ${SERVER_OUT_FILE} ${SERVER_PID_FILE} &
- fi
- FAIL_BOOT_ON_SITUATIONAL_CONFIG_ERROR=${FAIL_BOOT_ON_SITUATIONAL_CONFIG_ERROR:-true} 
- SERVER_OUT_MONITOR_INTERVAL=${SERVER_OUT_MONITOR_INTERVAL:-3}
- if [ ${FAIL_BOOT_ON_SITUATIONAL_CONFIG_ERROR} == 'true' ] ; then
- ${SCRIPTPATH}/monitorLog.sh ${SERVER_OUT_FILE} ${SERVER_OUT_MONITOR_INTERVAL} &
- fi
- waitForShutdownMarker
-}
-
 # Define helper fn to copy sit cfg xml files from one dir to another
 # $src_dir files are assumed to start with $fil_prefix and end with .xml
 # Copied $tgt_dir files are stripped of their $fil_prefix
@@ -247,12 +248,18 @@ copySitCfg /weblogic-operator/introspector ${DOMAIN_HOME}/optconfig/jms
 copySitCfg /weblogic-operator/introspector ${DOMAIN_HOME}/optconfig/jdbc 'Sit-Cfg-JDBC--'
 copySitCfg /weblogic-operator/introspector ${DOMAIN_HOME}/optconfig/diagnostics 'Sit-Cfg-WLDF--'
 
-
+#
+# Start WLS
+#
 
 if [ "${MOCK_WLS}" == 'true' ]; then
  mockWLS
- waitForShutdownMarker
 else
  startWLS
- waitUntilShutdown
 fi
+
+#
+# Wait forever. Kubernetes will monitor this pod via liveness and readyness probes.
+#
+
+waitForShutdownMarker

operator/src/main/resources/scripts/tailLog.sh

@@ -10,4 +10,29 @@
 #
 
 echo $$ > $2
-tail -F -n +0 $1
+
+while true ; do
+ if [ -f $1 ]; then
+ tail -F -n +0 $1 || sleep 10
+ fi
+ sleep 0.1
+done
+
+#
+# Work around note:
+#
+# The forever loop and '[ -f $1 ]' check above work around an
+# unexpected behavior from 'tail -F'. The '-F' expected
+# behavior is meant to handle 'rolling' files by both:
+#
+# A- Waiting until the file appears instead of exiting
+# with an error code.
+#
+# B- Once the file is found, gracefully handling the file
+# getting deleted or moved (by pausing while the file
+# is gone, and starting up again once a new file with
+# the same name appears in its place).
+#
+# But 'A' is not working on WL pods and thus the work around.
+# (Strangely and thankfully 'B' works fine.)
+#