fix #3

Introducing text alias for steps

seqTemplate.sh

@@ -4,11 +4,14 @@
 ## Sequencer interface:
 ##   - step_[1 - 255]_info [STEP NUMBER]
 ##        functions providing short header for help and user interaction
+##   - step_[1 - 255]_alias
+##        (optional) provide a string as alias for this step number
 ##   - step_[1 - 255] [STEP NUMBER]
-##        functions performing custom operations
+##        performing custom shell operations
 ## 
 
 step_1_info() { echo "Step $1 header"; }
+step_1_alias() { ALIAS="begin"; }
 step_1() {
   cat .nofile
   saveReturn $?
@@ -32,15 +35,19 @@ step_10() {
 }
 
 step_11_info() { echo "Step $1 header"; }
+step_11_alias() { ALIAS="elf"; }
 step_11() {
   echo elf
 }
 
 # Sequence Revision
-VERSION_SEQREV=1
+VERSION_SEQREV=2
 
 # Workaround when called from different directory
 # Not needed when path to sequencer is absolut
+#
+# It is recommended to copy or link sequencer.sh to
+# /usr/local/bin
 DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >>/dev/null 2>&1 && pwd )"
 # Path to local sequencer.sh script
 . ${DIR}/./sequencer/sequencer.sh

seqs/librenms.sh

@@ -126,6 +126,7 @@ step_40() {
 }
 
 step_42_info() { echo "Fix librenms permission"; }
+step_42_alias() { ALIAS="repair"; }
 step_42() {
   chown -R librenms:librenms /opt/librenms
   setfacl -d -m g::rwx /opt/librenms/bootstrap/cache /opt/librenms/storage /opt/librenms/logs /opt/librenms/rrd

sequencer/sequencer.sh

@@ -6,7 +6,7 @@
 
 ## Version information
 
-VERSION_REV=1
+VERSION_REV=2
 VERSION_MAJOR=0
 VERSION_MINOR=0
 
@@ -15,28 +15,29 @@ VERSION_MINOR=0
 QUIET=0
 ERNO=0
 MAX_STEP=255
+ALIAS=
 TEMPLATE_NAME=seqTemplateExample.sh
 VERSION_STRING="${VERSION_REV}.${VERSION_MAJOR}.${VERSION_MINOR}"
 
-function helpSequencer() {
-  echo "Usage: ${0##*/} [Options] [Step Number(s)]" 
+helpSequencer() {
+  echo "Usage: ${0##*/} [OPTIONS] [STEP NUMBER(s) or ALIAS]" 
   echo
-  echo " [Options]"
+  echo " [OPTIONS]"
   echo "  --help, -h   : Display help"
   echo "  --quiet, -q  : Don't ask for permission to execute steps"
   echo "                 If called without starting step number, only this help is shown"
   echo "  --version,-v : Display version of sequencer and revision of sequence"
   echo 
-  echo " [Step Number(s) 1-${MAX_STEP}]"
-  echo "     Single step number  : starting point of process"
-  echo "   Multiple step numbers : execute only given steps"
+  echo " [STEP NUMBER(s) 1-${MAX_STEP} or ALIAS]"
+  echo "     Single STEP or ALIAS : starting point of process"
+  echo "  Multiple STEPS or ALIAS : execute only given steps"
   echo "                            execute only one step with using special step 0"
   echo "                            ( e.g. only execute step 4: $0 4 0 )"
 }
 
 # endCheckEmpty [VariableName] [DESCRIPTION]
 #    DESCRIPTION : Optional text for error
-function endCheckEmpty() {
+endCheckEmpty() {
   local errorText=$1
   eval 'local ref=$'$1
 
@@ -49,14 +50,13 @@ function endCheckEmpty() {
   fi 
 }
 
-function existsFunction() {
+existsFunction() {
   local NOTFOUND=0
-  eval 'local ref=$'$1
   declare -F $1 &>>/dev/null || NOTFOUND=1
   return $NOTFOUND
 }
 
-function saveReturn() {
+saveReturn() {
   if [ $1 -ne 0 ] ; then
     ERNO=$1
   fi
@@ -64,7 +64,7 @@ function saveReturn() {
 
 # endReturn [-f]
 #   -f : force exit with $ERNO without user input
-function endReturn() {
+endReturn() {
   if [[ ( $ERNO -ne 0 && $QUIET -ne 0 ) || ( $ERNO -ne 0 && ! -z $1 && $1 == "-f" ) ]] ; then
     echo
     echo -e "[Error] Return value $ERNO detected.\nAborting installation."
@@ -91,7 +91,7 @@ function endReturn() {
 # execute [-q] <Step Number>
 #    -q: don't stop and don't report step functions which cannot be found 
 # execute given step_<Step Number> function
-function execute() {
+execute() {
   local NOTFOUND=0
   local NOREPORT=0
 
@@ -133,11 +133,36 @@ function execute() {
   fi
 }
 
+# checkStep <Step Number or Alias>
+#  return 0 - for invalid step
+# Check sanitiy of step number or
+# Check if alias exists
+checkStep() {
+  if (( $1 < 1 ||  $1 > $MAX_STEP )) ; then
+    eval 'local ref=$alias_'$1
+    if [ -z $ref ] || [ "$ref" == "$1" ] ; then
+      return 0 
+    else
+      return $ref
+    fi
+  else
+    return $1
+  fi
+}
+
 # continous <Starting Step Number>
 # (max $MAX_STEP)
 # execute installation continously from given starting step
-function continous() {
-  for ((i=$1; i<=${MAX_STEP}; i++)); do
+continous() {
+  local step=0
+
+  checkStep $1
+  step=$?
+  if [[ $step == 0 ]] ; then
+    return 1
+  fi
+  
+  for ((i=$step; i<=${MAX_STEP}; i++)); do
     execute -q $i
     local res=$?
     if [ $res -ne 0 ] ; then
@@ -149,19 +174,22 @@ function continous() {
 # selection <Step Number List (separated by space)>
 # execute given step list
 # e.g.: selection -q 1 4 12
-function selection() {
+selection() {
+  local step=0
   for i in $@ ; do
+    checkStep $i
+    step=$?
     # stop on step 0 
-  if [ $i -eq 0 ] ; then
+    if [ $step -eq 0 ] ; then
       break
     else 
-    execute $i
+      execute $step
     fi
   done
 }
 
 # Creating a minimal step definition template
-function createTemplate() {
+createTemplate() {
   if [ -f $TEMPLATE_NAME ] ; then
     return 1
   fi
@@ -169,18 +197,38 @@ function createTemplate() {
   echo >> $TEMPLATE_NAME
   echo "# Step 1 is mandatory" >> $TEMPLATE_NAME
   echo "step_1_info() { echo \"My custom step \$1\"; }" >> $TEMPLATE_NAME
+  echo "step_1_alias() { ALIAS=\"begin\"; }" >> $TEMPLATE_NAME
   echo "step_1() {" >> $TEMPLATE_NAME
   echo "  echo \"Doing something...\"" >> $TEMPLATE_NAME
   echo "}" >> $TEMPLATE_NAME
   echo >> $TEMPLATE_NAME
+  echo "VERSION_SEQREV=2" >> $TEMPLATE_NAME
   echo ". $0" >> $TEMPLATE_NAME
 
   chmod +x $TEMPLATE_NAME
   return 0
 }
 
+# Parse alias functions "step_[STEP NUBER]_alias" to create 
+# back reference variable of schema: 
+# alias_[ALIAS]=[STEP NUMBER]
+parseAlias() {
+  for ((i=1; i<=${MAX_STEP}; i++)); do
+    # Check for alias definition
+    existsFunction step_${i}_alias
+    if [ $? -ne 0 ] ; then
+      continue
+    fi
+
+    # Function writes global ALIAS variable
+    step_${i}_alias
+
+    eval 'alias_'$ALIAS'='$i
+  done
+}
+
 # Always display sequencer help and, if available, sequence help
-function displayHelp() {
+displayHelp() {
 
   helpSequencer
 
@@ -205,7 +253,7 @@ function displayHelp() {
     esac
     exit 1;
   else
-    echo "  Step documentation:"
+    echo "  Step (= alias) documentation:"
     for ((i=1; i<=${MAX_STEP}; i++)); do
 
       # Display step reference in help if step function exists 
@@ -213,7 +261,17 @@ function displayHelp() {
       if [ $? -ne 0 ] ; then
         continue
       fi
-      printf '    Step %3s : ' $i
+      printf '    Step %3s ' $i
+
+      # Display alias if exists
+      existsFunction step_${i}_alias
+      if [ $? -eq 0 ] ; then
+        step_${i}_alias 
+        echo " = $ALIAS" 
+        printf '              : '
+      else
+        echo -n " : "
+      fi
 
       # Display step help only if info function exists
       existsFunction step_${i}_info
@@ -227,7 +285,7 @@ function displayHelp() {
 }
 
 # showVersion
-function showVersion() {
+showVersion() {
   echo    "Sequencer    ${VERSION_STRING}"
   echo -n "Seq Revision "
   if [ ! -z "${VERSION_SEQREV}" ] ; then
@@ -282,6 +340,8 @@ main() {
     fi
   fi
 
+  parseAlias
+
   # check if more than one step is given and select execution mode
   if [ ! -z $2 ] ; then
     selection $@