Implement cache

Author: s-dwinter

.gitignore

@@ -25,3 +25,6 @@ go.work
 
 # goreleaser
 dist/
+
+# temporary files
+tmp/

alias.go

@@ -24,10 +24,10 @@ import (
 // Engine initializes external store client and template.
 type Engine = engine.Engine
 
-var (
-	// NewConfigFromFile returns a new Config from file.
-	NewConfigFromFile = config.NewFromFile
+// Config is the configuration for this library.
+type Config = config.Config
 
+var (
 	// NewEngine returns a new Engine.
 	NewEngine = engine.New
 )

go.mod

@@ -9,6 +9,7 @@ require (
 	github.com/aws/aws-sdk-go-v2/service/secretsmanager v1.29.1
 	github.com/aws/aws-sdk-go-v2/service/ssm v1.50.4
 	github.com/spf13/cobra v1.8.0
+	golang.org/x/crypto v0.3.0
 	sigs.k8s.io/yaml v1.4.0
 )
 
@@ -36,6 +37,5 @@ require (
 	github.com/shopspring/decimal v1.2.0 // indirect
 	github.com/spf13/cast v1.3.1 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
-	golang.org/x/crypto v0.3.0 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 )

internal/client/aws.go

@@ -25,6 +25,7 @@ import (
 	kmsTypes "github.com/aws/aws-sdk-go-v2/service/secretsmanager/types"
 	"github.com/aws/aws-sdk-go-v2/service/ssm"
 	ssmTypes "github.com/aws/aws-sdk-go-v2/service/ssm/types"
+	"github.com/dwango/yashiro/internal/values"
 	"github.com/dwango/yashiro/pkg/config"
 )
 
@@ -56,8 +57,8 @@ func newAwsClient(cfg *config.AwsConfig) (Client, error) {
 	}, nil
 }
 
-func (c awsClient) GetValues(ctx context.Context, ignoreNotFound bool) (Values, error) {
-	values := make(Values, len(c.parameterStoreValue)+len(c.secretsManagerValue))
+func (c awsClient) GetValues(ctx context.Context, ignoreNotFound bool) (values.Values, error) {
+	values := make(values.Values, len(c.parameterStoreValue)+len(c.secretsManagerValue))
 
 	for _, v := range c.parameterStoreValue {
 		output, err := c.ssmClient.GetParameter(ctx, &ssm.GetParameterInput{

internal/client/aws_test.go

@@ -25,6 +25,7 @@ import (
 	kmsTypes "github.com/aws/aws-sdk-go-v2/service/secretsmanager/types"
 	"github.com/aws/aws-sdk-go-v2/service/ssm"
 	ssmTypes "github.com/aws/aws-sdk-go-v2/service/ssm/types"
+	"github.com/dwango/yashiro/internal/values"
 	"github.com/dwango/yashiro/pkg/config"
 )
 
@@ -109,7 +110,7 @@ func Test_awsClient_GetValues(t *testing.T) {
 		name    string
 		fields  fields
 		args    args
-		want    Values
+		want    values.Values
 		wantErr bool
 	}{
 		{
@@ -128,7 +129,7 @@ func Test_awsClient_GetValues(t *testing.T) {
 				ctx:            context.Background(),
 				ignoreNotFound: false,
 			},
-			want: Values{"ssmKey": "test", "kmsKey": "test"},
+			want: values.Values{"ssmKey": "test", "kmsKey": "test"},
 		},
 		{
 			name: "ok: json",
@@ -156,7 +157,7 @@ func Test_awsClient_GetValues(t *testing.T) {
 				ctx:            context.Background(),
 				ignoreNotFound: false,
 			},
-			want: Values{"ssmKey": map[string]any{"key": "value"}, "kmsKey": map[string]any{"key": "value"}},
+			want: values.Values{"ssmKey": map[string]any{"key": "value"}, "kmsKey": map[string]any{"key": "value"}},
 		},
 		{
 			name: "ok: ignore not found error",
@@ -174,7 +175,7 @@ func Test_awsClient_GetValues(t *testing.T) {
 				ctx:            context.Background(),
 				ignoreNotFound: true,
 			},
-			want: Values{},
+			want: values.Values{},
 		},
 		{
 			name: "error: return not found from ssm",

internal/client/cache.go

@@ -0,0 +1,60 @@
+/**
+ * Copyright 2024 DWANGO Co., Ltd.
+ *
+ * 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
+ *
+ *     https://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 client
+
+import (
+	"context"
+
+	"github.com/dwango/yashiro/internal/client/cache"
+	"github.com/dwango/yashiro/internal/values"
+)
+
+type clientWithCache struct {
+	client Client
+	cache  cache.Cache
+}
+
+func newClientWithCache(client Client, cache cache.Cache) Client {
+	return &clientWithCache{
+		client: client,
+		cache:  cache,
+	}
+}
+
+// GetValues implements Client.
+func (c *clientWithCache) GetValues(ctx context.Context, ignoreNotFound bool) (values.Values, error) {
+	val, expired, err := c.cache.Load(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	// if cache is empty, get values from external store.
+	if len(val) == 0 || expired {
+		val, err = c.client.GetValues(ctx, ignoreNotFound)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	// save values to cache
+	if expired {
+		if err := c.cache.Save(ctx, val); err != nil {
+			return nil, err
+		}
+	}
+
+	return val, nil
+}

internal/client/cache/cache.go

@@ -0,0 +1,49 @@
+/**
+ * Copyright 2024 DWANGO Co., Ltd.
+ *
+ * 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
+ *
+ *     https://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 cache
+
+import (
+	"context"
+	"errors"
+	"fmt"
+
+	"github.com/dwango/yashiro/internal/values"
+	"github.com/dwango/yashiro/pkg/config"
+)
+
+var (
+	ErrInvalidCacheType = errors.New("invalid cache type")
+)
+
+type Cache interface {
+	// Load returns values from cache and whether or not cache is expired. If cache is empty,
+	// returned values is empty and expired=true.
+	Load(ctx context.Context) (values.Values, bool, error)
+
+	// Save saves values to cache.
+	Save(ctx context.Context, val values.Values) error
+}
+
+func New(cfg config.CacheConfig) (Cache, error) {
+	switch cfg.Type {
+	case config.CacheTypeUnspecified, config.CacheTypeMemory:
+		return newMemoryCache()
+	case config.CacheTypeFile:
+		return newFileCache(cfg.File)
+	default:
+		return nil, fmt.Errorf("%w: %s", ErrInvalidCacheType, cfg.Type)
+	}
+}