feat: hooks (#70)

* Hooks

Hook system to allow further customization at specific steps of the installation process.

- before/after_prepare_environment
- before/after_disk_configuration
- before/after_download_stage3
- before/after_extract_stage3

- before/after_install
- before/after_configure_base_system
- before/after_configure_portage
- before/after_install_kernel

* add hook examples

* fix: remove eval

gentoo.conf.example

@@ -286,3 +286,76 @@ ROOT_SSH_AUTHORIZED_KEYS=""
 # To prove that you have read and edited the config
 # properly, set the following value to true.
 I_HAVE_READ_AND_EDITED_THE_CONFIG_PROPERLY=false
+
+################################################
+# Hooks
+
+# before_prepare_environment() {
+#   einfo 'before prepare environment'
+# }
+
+# after_prepare_environment() {
+#   einfo 'after prepare environment'
+# }
+
+# before_disk_configuration() {
+#   einfo 'before disk configuration'
+# }
+
+# after_disk_configuration() {
+#   einfo 'after disk configuration'
+# }
+
+# before_download_stage3() {
+#   einfo "stage3 basename: $1"
+#   einfo 'before download stage3'
+# }
+
+# after_download_stage3() {
+#   einfo "stage3 downloaded file name: $1"
+#   einfo 'after download stage3'
+# }
+
+# before_extract_stage3() {
+#   einfo "stage3 downloaded file path: $1"
+#   einfo "root mountpoint: $1"
+#   einfo 'before extract stage3'
+# }
+
+# after_extract_stage3() {
+#   einfo "stage3 downloaded file path: $1"
+#   einfo "root mountpoint: $1"
+#   einfo 'after extract stage3'
+# }
+
+# before_install() {
+#   einfo 'before install'
+# }
+
+# after_install() {
+#   einfo 'after install'
+# }
+
+# before_configure_base_system() {
+#   einfo 'before configure base system'
+# }
+
+# after_configure_base_system() {
+#   einfo 'after configure base system'
+# }
+
+# before_configure_portage() {
+#   einfo 'before configure portage'
+# }
+
+# after_configure_portage() {
+#   einfo 'after configure portage'
+# }
+
+# before_install_kernel() {
+#   einfo 'before install kernel'
+# }
+
+# after_install_kernel() {
+#   einfo 'after install kernel'
+# }

scripts/functions.sh

@@ -64,6 +64,8 @@ function preprocess_config() {
 }
 
 function prepare_installation_environment() {
+	maybe_exec 'before_prepare_environment'
+
 	einfo "Preparing installation environment"
 
 	local wanted_programs=(
@@ -94,6 +96,8 @@ function prepare_installation_environment() {
 
 	# Sync time now to prevent issues later
 	sync_time
+
+	maybe_exec 'after_prepare_environment'
 }
 
 function check_encryption_key() {
@@ -735,6 +739,8 @@ function apply_disk_configuration() {
 		|| die "Aborted"
 	countdown "Applying in " 5
 
+	maybe_exec 'before_disk_configuration'
+
 	einfo "Applying disk configuration"
 	apply_disk_actions
 
@@ -742,6 +748,8 @@ function apply_disk_configuration() {
 	elog "New lsblk output:"
 	for_line_in <(lsblk \
 		|| die "Error in lsblk") elog
+
+	maybe_exec 'after_disk_configuration'
 }
 
 function mount_efivars() {
@@ -819,6 +827,8 @@ function download_stage3() {
 	# File to indiciate successful verification
 	CURRENT_STAGE3_VERIFIED="${CURRENT_STAGE3}.verified"
 
+	maybe_exec 'before_download_stage3' "$STAGE3_BASENAME"
+
 	# Download file if not already downloaded
 	if [[ -e $CURRENT_STAGE3_VERIFIED ]]; then
 		einfo "$STAGE3_BASENAME tarball already downloaded and verified"
@@ -855,6 +865,8 @@ function download_stage3() {
 		# Create verification file in case the script is restarted
 		touch_or_die 0644 "$CURRENT_STAGE3_VERIFIED"
 	fi
+
+	maybe_exec 'after_download_stage3' "${CURRENT_STAGE3}"
 }
 
 function extract_stage3() {
@@ -865,6 +877,8 @@ function extract_stage3() {
 	[[ -e "$TMP_DIR/$CURRENT_STAGE3" ]] \
 		|| die "stage3 file does not exist"
 
+	maybe_exec 'before_extract_stage3' "$TMP_DIR/$CURRENT_STAGE3" "$ROOT_MOUNTPOINT"
+
 	# Go to root directory
 	cd "$ROOT_MOUNTPOINT" \
 		|| die "Could not move to '$ROOT_MOUNTPOINT'"
@@ -879,6 +893,8 @@ function extract_stage3() {
 		|| die "Error while extracting tarball"
 	cd "$TMP_DIR" \
 		|| die "Could not cd into '$TMP_DIR'"
+
+	maybe_exec 'after_extract_stage3' "$TMP_DIR/$CURRENT_STAGE3" "$ROOT_MOUNTPOINT"
 }
 
 function gentoo_umount() {

scripts/main.sh

@@ -320,6 +320,8 @@ function generate_fstab() {
 function main_install_gentoo_in_chroot() {
 	[[ $# == 0 ]] || die "Too many arguments"
 
+	maybe_exec 'before_install'
+
 	# Remove the root password, making the account accessible for automated
 	# tasks during the period of installation.
 	einfo "Clearing root password"
@@ -342,9 +344,12 @@ function main_install_gentoo_in_chroot() {
 	try emerge-webrsync
 
 	# Configure basic system things like timezone, locale, ...
+	maybe_exec 'before_configure_base_system'
 	configure_base_system
+	maybe_exec 'after_configure_base_system'
 
 	# Prepare portage environment
+	maybe_exec 'before_configure_portage'
 	configure_portage
 
 	# Install git (for git portage overlays)
@@ -372,6 +377,7 @@ EOF
 			|| die "Could not delete obsolete rsync gentoo repository"
 		try emerge --sync
 	fi
+	maybe_exec 'after_configure_portage'
 
 	einfo "Generating ssh host keys"
 	try ssh-keygen -A
@@ -421,7 +427,9 @@ EOF
 	fi
 
 	# Install kernel and initramfs
+	maybe_exec 'before_install_kernel'
 	install_kernel
+	maybe_exec 'after_install_kernel'
 
 	# Generate a valid fstab file
 	generate_fstab
@@ -487,6 +495,8 @@ EOF
 			|| die "Could not modify /etc/portage/make.conf"
 	fi
 
+	maybe_exec 'after_install'
+
 	einfo "Gentoo installation complete."
 	[[ $USED_LUKS == "true" ]] \
 		&& einfo "A backup of your luks headers can be found at '$LUKS_HEADER_BACKUP_DIR', in case you want to have a backup."

scripts/utils.sh

@@ -445,3 +445,9 @@ function check_wanted_programs() {
 		ask "Continue without recommended programs?"
 	fi
 }
+
+# exec function if defined
+# $@ function name and arguments
+function maybe_exec() {
+	type "$1" &>/dev/null && "$@"
+}