From 9e354b2a16ec65d5429686a46ddef4e01d49c452 Mon Sep 17 00:00:00 2001
From: wfender <wfender@google.com>
Date: Tue, 23 Jun 2020 15:05:54 -0700
Subject: [PATCH] Added script to generate module level dependency graph.

Added comments and switched to _output for bentheelder.
Added error checking for logicalhan.
Fixed egrep error.
Added dedupe logic.
Added staging only option.
Fixed ls -> find.
---
 hack/module-graph.sh | 66 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)
 create mode 100755 hack/module-graph.sh

diff --git a/hack/module-graph.sh b/hack/module-graph.sh
new file mode 100755
index 00000000000..9cdccd157a4
--- /dev/null
+++ b/hack/module-graph.sh
@@ -0,0 +1,66 @@
+#!/usr/bin/env bash
+
+# Copyright 2020 The Kubernetes Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This script generates a jpg image of our internal dependency graph.
+# It relies on go mod and dot to do so and should be run from K8s root.
+# TODO: Containerize the script to remove dependency issues with go mod and dot.
+
+# To generate graph with all Kubernetes modules run
+# ./hack/module-graph.sh
+# To generate graph with just staging modules run
+# ./hack/module-graph.sh staging
+
+error_exit()
+{
+	echo "$1" 1>&2
+	exit 1
+}
+
+staging_dependencies()
+{
+	relevant_modules="(k8s.io/kubernetes|$(find staging/src/k8s.io -maxdepth 1 -mindepth 1 | sed -E 's|staging/src/k8s.io|k8s.io|g' | tr '\n' '|' | sed 's#|$##' ))"
+	# Generating lines of the form " k8s_io_kubernetes -> k8s_io_api"
+	# Use only the directories in staging
+	# Trimming away version info
+	# Replacing non DOT (graph description language) characters with underscores
+	# Dedupe lines
+	# Inserting needed arrow.
+	# Indenting the line appropriately
+	go mod graph | grep -E "^${relevant_modules}(@.*| )${relevant_modules}@.*$" | sed -E 's|@\S+ | |g' | sed -E 's|@\S+$||g' | sed -E 's/[\.\/\-]/_/g' | sort | uniq | sed -E 's| | -> |g' | sed -E 's|^|    |g' >> _output/module-dependencies.dot || error_exit "Failed to generate staging dependencies in DOT file"
+}
+
+kubernetes_dependencies()
+{
+	# Generating lines of the form " k8s_io_kubernetes -> k8s_io_api"
+	# Excluding all non Kubernetes dependencies
+	# Trimming away version info
+	# Replacing non DOT (graph description language) characters with underscores
+	# Dedupe lines
+	# Inserting needed arrow.
+	# Indenting the line appropriately
+	go mod graph | grep -E "^.*k8s.io.*k8s.io.*$" | sed -E 's|@\S+ | |g' | sed -E 's|@\S+$||g' | sed -E 's/[\.\/\-]/_/g' | sort | uniq | sed -E 's| | -> |g' | sed -E 's|^|    |g' >> _output/module-dependencies.dot || error_exit "Failed to generate kubernetes dependencies in DOT file"
+}
+
+echo "digraph module_dependencies {" > _output/module-dependencies.dot || error_exit "Failed to open DOT file"
+if [[ -n "$1" && $1 == "staging" ]]; then
+	echo "Generating just staging modules"
+	staging_dependencies
+else
+	echo "Generating all Kubernetes modules"
+	kubernetes_dependencies
+fi
+echo "}" >> _output/module-dependencies.dot || error_exit "Failed to close DOT file"
+dot -Gratio=1,1 -Nwidth=2 -Nheight=2 -Nfontsize=48 -Earrowsize=8 -Tjpg _output/module-dependencies.dot -o _output/module-dependencies.jpg || error_exit "Failed to generate graph from DOT file"