Experimental version. Cleaned up syntax and created common library functions.

install_and_cache_pkgs.sh

@@ -3,22 +3,23 @@
 # Fail on any error.
 set -e
 
+# Include library.
+script_dir="$(dirname -- "$(realpath -- "${0}")")"
+source "${script_dir}/lib"
+
 # Directory that holds the cached packages.
 cache_dir="${1}"
 
 # List of the packages to use.
-packages="${@:2}"
+input_packages="${@:2}"
 
-# Sort these packages by name and split on commas.
-packages=$(echo "${packages}" | sed 's/[\s,]+/ /g' | tr ' ' '\n' | sort | tr '\n' ' ')
-
-# Remove extraneous spaces
-packages="$(echo "${packages}" | sed 's/\s\+/ /g;s/^\s\+//g;s/\s\+$//g')"
+# Trim commas, excess spaces, and sort.
+packages="$(normalize_package_list "${input_packages}")"
 
 package_count=$(echo "${packages}" | wc -w)
 echo "Clean installing and caching ${package_count} package(s)."
 echo "Package list:"
-for package in ${packages}; do
+for package in "${packages}"; do
   echo "- ${package}"
 done
 
@@ -28,21 +29,23 @@ echo "done."
 
 manifest=
 echo "Clean installing and caching ${package_count} packages..."
-for package in ${packages}; do
-  echo "- ${package}"
-  echo -n "  Installing..."
+for package in "${packages}"; do
+  get_package_name_ver "${package}" # -> package_name, package_ver
+  package_deps="$(apt-get install --dry-run --yes "${package_name}" | grep "^Inst" | awk '{print $2}')"
 
-  # Gather a list of all packages apt installs to make this package work
-  required_packages=$(apt-get install --dry-run --yes "${package}" | grep -Po "(?<=Inst )[^\s]+" || echo "${package}")
-  echo "Package ${package} installs the following packages: ${required_packages//$'\n'/, }"
+  echo "- ${package_name}"
+  echo "  * Version: ${package_ver}"
+  echo "  * Dependencies: ${package_deps}"
+  echo -n "  * Installing..."
+  # Zero interaction while installing or upgrading the system via apt.
   sudo DEBIAN_FRONTEND=noninteractive apt-get --yes install "${package}" > /dev/null
-
   echo "done."
 
-  for cache_package in ${required_packages}; do
+  for cache_package in "${package_deps}"; do
     cache_filepath="${cache_dir}/${cache_package}.tar.gz"
-    if [ ! -f "${cache_filepath}" ]; then
-      package_name="$(echo "${cache_package}" | cut -d"=" -f1)"
+
+    if test ! -f "${cache_filepath}"; then
+      get_package_name_ver "${cache_package}" # -> package_name, package_ver      
       echo -n "  Caching ${package_name} to ${cache_filepath}..."
       # Pipe all package files (no folders) to Tar.
       dpkg -L "${package_name}" |
@@ -60,6 +63,6 @@ echo "done."
 
 manifest_filepath="${cache_dir}/manifest.log"
 echo -n "Writing package manifest to ${manifest_filepath}..."
-# Remove trailing comma.
-echo ${manifest:0:-1} > ${manifest_filepath}
+# Remove trailing comma and write to manifest file.
+echo "${manifest:0:-1}" > "${manifest_filepath}"
 echo "done."

lib.sh

@@ -0,0 +1,23 @@
+#!/bin/bash
+
+# Sort these packages by name and split on commas.
+function normalize_package_list {
+  stripped="$(echo \"${0}\" | sed 's/,//g')"
+  # Remove extraneous spaces at the middle, beginning, and end.
+  trimmed="$(echo \"${stripped}\" | sed 's/\s\+/ /g; s/^\s\+//g; s/\s\+$//g')"  
+  echo "$(\"${trimmed}\" | sort)"
+}
+
+# Split fully qualified package into name and version
+function get_package_name_ver {
+  IFS=\= read name ver <<< "${0}"
+  # If version not found in the fully qualified package value.
+  if test -z "${ver}"; then
+    ver="$(grep "Version:" <<< "$(apt show ${name})" | awk '{print $2}')"
+  fi
+  echo 'package_name="${name}"; package_ver="${ver}"'
+}
+
+function blah {
+  > /dev/null 2>&1
+}

pre_cache_action.sh

@@ -1,5 +1,9 @@
 #!/bin/bash
 
+# Include library.
+script_dir="$(dirname -- "$(realpath -- "${0}")")"
+source "${script_dir}/lib"
+
 # Directory that holds the cached packages.
 cache_dir="${1}"
 
@@ -7,22 +11,23 @@ cache_dir="${1}"
 cache_version="${2}"
 
 # List of the packages to use.
-packages="${@:3}"
+input_packages="${@:3}"
 
-# Sort these packages by name and split on commas.
-packages=$(echo "${packages}" | sed 's/[\s,]+/ /g' | tr ' ' '\n' | sort | tr '\n' ' ')
+# Trim commas, excess spaces, and sort.
+packages="$(normalize_package_list "${input_packages}")"
 
 # Create cache directory so artifacts can be saved.
 mkdir -p "${cache_dir}"
 
 echo -n "Validating action arguments (version='${cache_version}', packages='${packages}')...";
 
-if echo "${cache_version}" | grep -q " " > /dev/null; then
+if grep -q " " <<< "${cache_version}"; then
   echo "aborted." 
   echo "Version value '${cache_version}' cannot contain spaces." >&2
   exit 1
 fi
-if [ "${packages}" == "" ]; then
+# Is length of string zero?
+if test -z "${packages}"; then
   echo "aborted." 
   echo "Packages argument cannot be empty." >&2
   exit 2
@@ -33,24 +38,16 @@ echo -n "Updating APT package list..."
 sudo apt-get update > /dev/null
 echo "done."
 
+versioned_packages=""
 echo -n "Verifying packages..."
-for package in ${packages}; do
-  if echo "${package}" | grep -q "="; then
-    package_name=$(echo "${package}" | cut -d "=" -f1)
-    package_ver=$(echo "${package}" | cut -d "=" -f2)
-  else
-    package_name="${package}"
-  fi
-  apt_show=$(apt show "${package}")
-  if echo ${apt_show} | grep -qi "No packages found" > /dev/null; then
+for package in ${packages}; do 
+  if test ! "$(apt show "${package}")"; then
     echo "aborted."
     echo "Package '${package}' not found." >&2
     exit 3
   fi
-  if [ -z "${package_ver}" ]; then
-    package_ver=$(echo "${apt_show}" | grep -Po "(?<=Version: )[^\s]+")
-  fi
-  package_list="${package_list} ${package_name}=${package_ver}"
+  get_package_name_ver "${package}" # -> package_name, package_ver  
+  versioned_packages="${versioned_packages} ${package_name}=${package_ver}"
 done
 echo "done."
 
@@ -59,15 +56,15 @@ set -e
 
 echo "Creating cache key..."
 
-# Remove extraneous spaces
-package_list="$(echo "${package_list}" | sed 's/\s\+/ /g;s/^\s\+//g;s/\s\+$//g')"
-echo "- Normalized package list is '$package_list'."
+# TODO Can we prove this will happen again?
+normalized_versioned_packages="$(normalize_package_list "${versioned_packages}")"
+echo "- Normalized package list is '${normalized_versioned_packages}'."
 
-value=$(echo "${package_list} @ ${cache_version}")
+value="$(echo "${normalized_versioned_packages} @ ${cache_version}")"
 echo "- Value to hash is '${value}'."
 
-key=$(echo "${value}" | md5sum | /bin/cut -f1 -d' ')
-echo "- Value hashed as '$key'."
+key="$(echo "${value}" | md5sum | /bin/cut -f1 -d' ')"
+echo "- Value hashed as '${key}'."
 
 echo "done."
 

restore_pkgs.sh

@@ -17,7 +17,7 @@ for cache_filepath in ${cache_filepaths}; do
 done
 
 echo "Reading from manifest..."
-for logline in $(cat "${cache_dir}/manifest.log" | tr ',' '\n' ); do
+for logline in "$(cat "${cache_dir}/manifest.log" | tr ',' '\n' )"; do
   echo "- $(echo "${logline}" | tr ':' ' ')"
 done
 echo "done."