Extend containerd registry mirror config

pkg/containerruntime/config.go

@@ -21,6 +21,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"net/url"
+	"regexp"
 	"strings"
 
 	corev1 "k8s.io/api/core/v1"
@@ -45,27 +46,38 @@ func BuildConfig(opts Opts) (Config, error) {
 		}
 	}
 
-	var registryMirrors []string
+	// we want to match e.g. docker.io=registry.docker-cn.com, having docker.io as the first
+	// match group and registry.docker-cn.com as the second one.
+	registryMirrorRegexp := regexp.MustCompile(`^([a-zA-Z0-9\.-]+)=(.*)`)
+
+	if opts.ContainerdRegistryMirrors == nil {
+		opts.ContainerdRegistryMirrors = make(RegistryMirrorsFlags)
+	}
+
 	for _, mirror := range strings.Split(opts.RegistryMirrors, ",") {
 		if trimmedMirror := strings.TrimSpace(mirror); trimmedMirror != "" {
-			if !strings.HasPrefix(mirror, "http") {
-				trimmedMirror = "https://" + mirror
+			registry := "docker.io"
+
+			if matches := registryMirrorRegexp.FindStringSubmatch(trimmedMirror); matches != nil {
+				registry = matches[1]
+				trimmedMirror = matches[2]
+			}
+
+			if !strings.HasPrefix(trimmedMirror, "http") {
+				trimmedMirror = "https://" + trimmedMirror
 			}
 
 			_, err := url.Parse(trimmedMirror)
 			if err != nil {
 				return Config{}, fmt.Errorf("incorrect mirror provided: %w", err)
 			}
 
-			registryMirrors = append(registryMirrors, trimmedMirror)
-		}
-	}
+			if opts.ContainerdRegistryMirrors[registry] == nil {
+				opts.ContainerdRegistryMirrors[registry] = make([]string, 0, 1)
+			}
 
-	if len(registryMirrors) > 0 {
-		if opts.ContainerdRegistryMirrors == nil {
-			opts.ContainerdRegistryMirrors = make(RegistryMirrorsFlags)
+			opts.ContainerdRegistryMirrors[registry] = append(opts.ContainerdRegistryMirrors[registry], trimmedMirror)
 		}
-		opts.ContainerdRegistryMirrors["docker.io"] = registryMirrors
 	}
 
 	// Only validate registry credential here

pkg/containerruntime/config_test.go

@@ -0,0 +1,134 @@
+/*
+Copyright 2022 The Machine Controller 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 containerruntime
+
+import (
+	"errors"
+	"fmt"
+	"testing"
+)
+
+func TestContainerdRegistryMirror(t *testing.T) {
+	type testCase struct {
+		desc            string
+		flag            string
+		expectedMirrors map[string][]string
+		expectedError   error
+	}
+
+	testCases := []testCase{
+		{
+			desc:            "no registry mirrors set",
+			flag:            "",
+			expectedMirrors: map[string][]string{},
+			expectedError:   nil,
+		},
+
+		{
+			desc: "registry mirror without name and protocol",
+			flag: "registry-v1.docker.io",
+			expectedMirrors: map[string][]string{
+				"docker.io": {"https://registry-v1.docker.io"},
+			},
+			expectedError: nil,
+		},
+		{
+			desc: "multiple registry mirrors without name, with and without protocol",
+			flag: "registry-v1.docker.io,http://registry.docker-cn.com",
+			expectedMirrors: map[string][]string{
+				"docker.io": {
+					"https://registry-v1.docker.io",
+					"http://registry.docker-cn.com",
+				},
+			},
+			expectedError: nil,
+		},
+
+		{
+			desc: "registry mirror with name and without protocol",
+			flag: "quay.io=my-quay-io-mirror.example.com",
+			expectedMirrors: map[string][]string{
+				"quay.io": {"https://my-quay-io-mirror.example.com"},
+			},
+			expectedError: nil,
+		},
+		{
+			desc: "registry mirror with name and protocol",
+			flag: "quay.io=http://my-quay-io-mirror.example.com",
+			expectedMirrors: map[string][]string{
+				"quay.io": {"http://my-quay-io-mirror.example.com"},
+			},
+			expectedError: nil,
+		},
+		{
+			desc: "multiple registry mirrors with same name",
+			flag: "quay.io=http://my-quay-io-mirror.example.com,quay.io=example.net",
+			expectedMirrors: map[string][]string{
+				"quay.io": {
+					"http://my-quay-io-mirror.example.com",
+					"https://example.net",
+				},
+			},
+			expectedError: nil,
+		},
+
+		{
+			desc: "complex example",
+			flag: "quay.io=http://my-quay-io-mirror.example.com,quay.io=example.net," +
+				"registry-v1.docker.io,http://registry.docker-cn.com," +
+				"ghcr.io=http://foo/bar",
+			expectedMirrors: map[string][]string{
+				"quay.io": {
+					"http://my-quay-io-mirror.example.com",
+					"https://example.net",
+				},
+				"docker.io": {
+					"https://registry-v1.docker.io",
+					"http://registry.docker-cn.com",
+				},
+				"ghcr.io": {
+					"http://foo/bar",
+				},
+			},
+			expectedError: nil,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.desc, func(t *testing.T) {
+			opts := Opts{
+				ContainerRuntime: containerdName,
+				RegistryMirrors:  tc.flag,
+			}
+
+			config, err := BuildConfig(opts)
+			if tc.expectedError != nil {
+				if !errors.Is(err, tc.expectedError) {
+					t.Errorf("expected error %q but got %q", tc.expectedError, err)
+				}
+			}
+
+			if err != nil {
+				t.Errorf("expected success but got error: %q", err)
+			}
+
+			if fmt.Sprint(config.RegistryMirrors) != fmt.Sprint(tc.expectedMirrors) {
+				t.Errorf("expected to get %v instead got: %v", tc.expectedMirrors, config.RegistryMirrors)
+			}
+		})
+	}
+}