From 74d58d94f5a32c28958a3d755dafb5983e1e98d8 Mon Sep 17 00:00:00 2001
From: Maxim Likhachev <envrm@yandex.ru>
Date: Wed, 11 May 2022 11:55:38 +0300
Subject: [PATCH] ++terraform-mermaid

---
 README.md                 |  1 +
 scripts/terraform-mermaid | 93 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 94 insertions(+)
 create mode 100755 scripts/terraform-mermaid

diff --git a/README.md b/README.md
index d8a3588..900f2da 100644
--- a/README.md
+++ b/README.md
@@ -101,6 +101,7 @@ will create the symbolic link for each script in the \<path> directory.
 - [how](scripts/how) shows dev cheat sheets using [cheat.sh](https://cheat.sh).
 - [robodoc2html](scripts/robodoc2html) converts a documentation in the robodoc format into html.
 - [terraform-compliance-generator](scripts/terraform-compliance-generator) makes a [terraform-compliance](https://terraform-compliance.com/) compatible BDD testing scenario.
+- [terraform-mermaid](scripts/terraform-mermaid) converts `terraform graph` output to Mermaid diagram.
 - [todolist](scripts/todolist) shows all `TODO` notes in current git repository.
 - [utable](scripts/utable) shows a Unicode table.
 - [vault-kv-tree](scripts/vault-kv-tree) shows all HashiCorp Vault's paths and keys recursively.
diff --git a/scripts/terraform-mermaid b/scripts/terraform-mermaid
new file mode 100755
index 0000000..6c38628
--- /dev/null
+++ b/scripts/terraform-mermaid
@@ -0,0 +1,93 @@
+#!/usr/bin/env bash
+
+#
+# Copyright (C) 2022, Maxim Lihachev, <envrm@yandex.ru>
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the Free
+# Software Foundation, version 3.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# this program. If not, see <https://www.gnu.org/licenses/>.
+#
+# terraform-mermaid can be used to convert `terraform graph` command output
+# from Graphviz to Mermaid format.
+
+# TODO: -s simple
+
+set -e
+set -o errtrace
+
+\unalias -a
+
+IFS=$' \t\n'
+
+show_help() {
+	echo -e "$(basename "$0") can be used to convert \`terraform graph' command output from Graphviz to Mermaid format.\n"
+	echo -e "USAGE: $(basename "$0") ?-m? ?-d DIRECTION??\n"
+
+	echo -e "Command line arguments:"
+	echo -e "    -h --help       Show this help"
+	echo -e "    -m --markdown   Put the output in triple back quotes (\`\`\`)"
+	echo -e "    -d --direction  Specify the direction of the graph (TB | BT | LR | RL; TB by default)"
+
+	echo
+	exit "${1:-0}"
+}
+
+UNKNOWN_ARGS=()
+
+while [[ $# -gt 0 ]]; do
+	key="$1"
+
+	case $key in
+		-h|--help)      show_help;;
+		-d|--direction) DIRECTION="$2"; shift; shift;;
+		-m|--markdown)  MARKDOWN="true"; shift;;
+		*)            UNKNOWN_ARGS+=("$1");  shift;;
+	esac
+done
+
+[ ${#UNKNOWN_ARGS} -gt 0 ] && echo "Unknown parameters: ${UNKNOWN_ARGS[*]}" >&2 && show_help 1
+
+declare -a MERMAID
+
+[ -n "$MARKDOWN" ] && MERMAID+=('```mermaid')
+
+MERMAID+=("graph ${DIRECTION:-TB}")
+
+GRAPH=$(terraform graph)
+
+mapfile -t MERMAID_GRAPH < <(
+	echo "$GRAPH" \
+		| grep -v 'meta\.count' \
+		| grep -- '->' \
+		| sed -E 's/"//g;
+			s/^[[:space:]]*|\\]|\[root\] | \((expand|close)\)//g;
+			s!provider.*/!provider:!g;
+			s/helm_release/helm/g;
+			s/null_resource\.//g;
+			s/kubernetes/k8s/g;
+			s/ -> / --> /g;
+			s/^(.*) --> (.*)$/\2 --> \1/;
+			s/(provider:[[:alnum:]_]*)/\1((\1))/;
+			s/((var|local).[[:alnum:]_]*)/\1{{\1}}/;
+			s/(helm\.[[:alnum:]_]*)/\1{{\1}}/;
+			s/(local_file\.[[:alnum:]_]*)/\1>\1]/;
+			s/default/defaulṭ/;
+			s/class/clasṣ/g;
+			/^provider:[[:alnum:]_]*/d;' \
+		| sed 's/^/    /'
+)
+
+MERMAID=("${MERMAID[@]}" "${MERMAID_GRAPH[@]}")
+
+[ -n "$MARKDOWN" ] && MERMAID+=('```')
+
+printf "%s\n" "${MERMAID[@]}"
+