install-header: Added --extract-only switchHEADmaster

This switch skips the deploy function as well as the cleanup process,
executing the extraction process before exiting. This will enable easier
debugging.

Note that this switch does not support a short version to avoid risk of
conflicting with downstream run.sh-provided switches (eg: -e).

1 files changed, 24 insertions, 4 deletions

diff --git a/install-header.sh b/install-header.sh
index 200e9c5..1470c8f 100755
--- a/install-header.sh
+++ b/install-header.sh
@@ -7,7 +7,8 @@ LENS=(                                       )
 export SELF             # Absolute path to the installer script (me!)
 export TMP              # Path to tmp install staging directory
 export PAYLOAD          # Path to the extracted payload directory
-export NOCLEANUP        # Do not clean up deploy resources. Useful for debugging
+export NOCLEANUP=0      # Do not clean up deploy resources. Useful for debugging
+export EXTRACTONLY=0    # Execute extract, skipping deployment and cleanup
 export DECOMPRESS='{{ DECOMPRESS }}' # Command to decompress data
 
 # Header:    0
@@ -49,6 +50,8 @@ extract_payload() {
 
 
 main() {
+  local args=(${@})
+
   SELFDIR="$(cd $(dirname ${0}) && pwd)"
   SELF="${SELFDIR}/$(basename ${0})"
   TMP="$(mktemp -d /tmp/installer-XXXXXXX)"
@@ -65,15 +68,32 @@ main() {
 
   source run.sh
 
-  # Function 'deploy' is provided by run.sh
-  if [ "$(type -t deploy)" == 'function' ]; then
+  for (( i = 0; i < ${#args[@]}; i++ )); do
+    # NOTE: Do not support short switches here to reduce the probability of
+    #       conflicting with  a switch provided by the downstream run.sh
+    if [ "${args[$i]}" = '--extract-only' ]; then
+      export EXTRACTONLY=1
+      export NOCLEANUP=1
+    fi
+  done
+
+  if [ "${EXTRACTONLY}" = '1' ]; then
+    printf 'Extracting...\n'
+    extract_payload
+    printf 'Installation payload available at "%s"\n' "${TMP}/pkg"
+    printf 'Skipping cleanup\n'
+    return 0
+  elif [ "$(type -t deploy)" == 'function' ]; then
+    # Function 'deploy' is provided by run.sh
     deploy ${@}
   else
     printf "ERROR: Deploy function not found.\n"
   fi
 
   # Cleanup
-  [ -z "${NOCLEANUP:-}" ] && rm -rf "${TMP}"
+  if [ "${NOCLEANUP}" -ne 0 ]; then
+    rm -rf "${TMP}"
+  fi
 }
 
 main ${@}