From 3e5f18d409e448f69e4f259fc451d4a0e5a7a548 Mon Sep 17 00:00:00 2001
From: Dennis Camera <dennis.camera@ssrq-sds-fds.ch>
Date: Sun, 25 Oct 2020 18:42:50 +0100
Subject: [PATCH] [type/__uci] Apply all commands in a single batch

---
 cdist/conf/type/__uci/files/uci_apply.sh | 43 ++++++++++++++++++++++++
 cdist/conf/type/__uci/gencode-remote     |  8 +++++
 cdist/conf/type/__uci/nonparallel        |  0
 3 files changed, 51 insertions(+)
 create mode 100644 cdist/conf/type/__uci/files/uci_apply.sh
 create mode 100644 cdist/conf/type/__uci/nonparallel

diff --git a/cdist/conf/type/__uci/files/uci_apply.sh b/cdist/conf/type/__uci/files/uci_apply.sh
new file mode 100644
index 00000000..63f94290
--- /dev/null
+++ b/cdist/conf/type/__uci/files/uci_apply.sh
@@ -0,0 +1,43 @@
+changes=$(uci changes)
+
+if test -n "${changes}"
+then
+	echo 'Uncommited UCI changes were found on the target:'
+	printf '%s\n\n' "${changes}"
+	echo 'This can be caused by manual changes or due to a previous failed run.'
+	echo 'Please investigate the situation, revert or commit the changes, and try again.'
+	exit 1
+fi >&2
+
+check_errors() {
+	# reads stdin and forwards non-empty lines to stderr.
+	# returns 0 if stdin is empty, else 1.
+	! grep -e . >&2
+}
+
+commit() {
+	uci commit
+}
+
+rollback() {
+	printf '\nAn error occurred when trying to commit UCI transaction!\n' >&2
+
+	uci changes \
+	| sed -e 's/^-//' -e 's/\..*\$//' \
+	| sort -u \
+	| while read -r _package
+	  do
+		  uci revert "${_package}"
+		  echo "${_package}"  # for logging
+	  done \
+	| awk '
+	  BEGIN { printf "Reverted changes in: " }
+	  { printf "%s%s", (FNR > 1 ? ", " : ""), $0 }
+	  END { printf "\n" }' >&2
+
+	return 1
+}
+
+uci_apply() {
+	uci batch 2>&1 | check_errors && commit || rollback
+}
diff --git a/cdist/conf/type/__uci/gencode-remote b/cdist/conf/type/__uci/gencode-remote
index a15f50a6..348d15a1 100755
--- a/cdist/conf/type/__uci/gencode-remote
+++ b/cdist/conf/type/__uci/gencode-remote
@@ -91,3 +91,11 @@ in
 		exit 1
 		;;
 esac
+
+if test -s "${__object:?}/files/uci_batch.txt"
+then
+	cat "${__type:?}/files/uci_apply.sh"
+	printf "uci_apply <<'EOF'\n"
+	cat "${__object:?}/files/uci_batch.txt"
+	printf '\nEOF\n'
+fi
diff --git a/cdist/conf/type/__uci/nonparallel b/cdist/conf/type/__uci/nonparallel
new file mode 100644
index 00000000..e69de29b