From 0a7967a68b63d4b4bae4787847efef98ef2467a5 Mon Sep 17 00:00:00 2001
From: yuzhipeng <yuzp1996@qq.com>
Date: Thu, 14 Mar 2024 16:12:35 +0800
Subject: [PATCH] Add func for selecting and mutating map element (#554)

Signed-off-by: yuzhipeng <zpyu@alauda.io>
---
 maps/maps_suite_test.go | 29 ++++++++++++++++++
 maps/select.go          | 35 +++++++++++++++++++++
 maps/select_test.go     | 67 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 131 insertions(+)
 create mode 100644 maps/maps_suite_test.go
 create mode 100644 maps/select.go
 create mode 100644 maps/select_test.go

diff --git a/maps/maps_suite_test.go b/maps/maps_suite_test.go
new file mode 100644
index 00000000..659e82c1
--- /dev/null
+++ b/maps/maps_suite_test.go
@@ -0,0 +1,29 @@
+/*
+Copyright 2024 The Katanomi 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.
+*/
+
+package maps
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+func TestMaps(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Maps Suite")
+}
diff --git a/maps/select.go b/maps/select.go
new file mode 100644
index 00000000..a6984939
--- /dev/null
+++ b/maps/select.go
@@ -0,0 +1,35 @@
+/*
+Copyright 2024 The Katanomi 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.
+*/
+
+package maps
+
+// MatchFunc return true if key and value match condition
+type MatchFunc func(key, value string) bool
+
+// MutateFunc return mutated key and value
+type MutateFunc func(key, value string) (string, string)
+
+// SelectAndMutateMap select elements from a map based on a match function and mutate it's key and value
+func SelectAndMutateMap(maps map[string]string, match MatchFunc, mutate MutateFunc) map[string]string {
+	result := make(map[string]string)
+	for key, value := range maps {
+		if match(key, value) {
+			key, value = mutate(key, value)
+			result[key] = value
+		}
+	}
+	return result
+}
diff --git a/maps/select_test.go b/maps/select_test.go
new file mode 100644
index 00000000..829cf935
--- /dev/null
+++ b/maps/select_test.go
@@ -0,0 +1,67 @@
+/*
+Copyright 2024 The Katanomi 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.
+*/
+
+// Package maps contains methods to operate maps of all kinds
+package maps
+
+import (
+	"strings"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var source = map[string]string{
+	"core-1": "1",
+	"core-2": "2",
+	"core-3": "3",
+}
+var _ = Describe("SelectAndMutateMap", func() {
+	DescribeTable("SelectAndMutateMap in different situation",
+		func(source map[string]string, match MatchFunc, mutate MutateFunc, expect map[string]string) {
+			result := SelectAndMutateMap(source, match, mutate)
+			Expect(result).To(Equal(expect))
+		},
+		Entry("return all the element",
+			source,
+			func(key string, value string) bool { return true },
+			func(key string, value string) (string, string) { return key, value },
+			source,
+		),
+		Entry("return core-1 element",
+			source,
+			func(key string, value string) bool {
+				return key == "core-1"
+			},
+			func(key string, value string) (string, string) { return key, value },
+			map[string]string{
+				"core-1": "1",
+			},
+		),
+		Entry("return mutated core-1 element",
+			source,
+			func(key string, value string) bool {
+				return key == "core-1"
+			},
+			func(key string, value string) (string, string) {
+				return strings.TrimPrefix(key, "core-"), value
+			},
+			map[string]string{
+				"1": "1",
+			},
+		),
+	)
+})