feat: Add UpdateTimestamps option

README.md

@@ -309,10 +309,13 @@ OPTIONS:
    --azblob.prefix value The Azure blob storage object prefix to use when
       using azblob proxy backend. [$BAZEL_REMOTE_AZBLOB_PREFIX]
 
+   --azblob.update_timestamps Whether to update timestamps of object on cache
+      hit. (default: false) [$BAZEL_REMOTE_AZBLOB_UPDATE_TIMESTAMPS]
+
    --azblob.auth_method value The Azure blob storage authentication method.
       This argument is required when an azblob proxy backend is used. Allowed
       values: client_certificate, client_secret, environment_credential,
-      default. [$BAZEL_REMOTE_AZBLOB_AUTH_METHOD]
+      shared_key, default. [$BAZEL_REMOTE_AZBLOB_AUTH_METHOD]
 
    --azblob.shared_key value The Azure blob storage account access key to use
       when using azblob proxy backend. Applies to AzBlob auth method(s):

cache/azblobproxy/azblobproxy.go

@@ -7,6 +7,7 @@ import (
 	"io"
 	"log"
 	"path"
+	"time"
 
 	"github.com/Azure/azure-sdk-for-go/sdk/azcore"
 	"github.com/Azure/azure-sdk-for-go/sdk/storage/azblob"
@@ -35,15 +36,16 @@ type uploadReq struct {
 }
 
 type azBlobCache struct {
-	containerClient *azblob.ContainerClient
-	storageAccount  string
-	container       string
-	prefix          string
-	v2mode          bool
-	uploadQueue     chan<- uploadReq
-	accessLogger    cache.Logger
-	errorLogger     cache.Logger
-	objectKey       func(hash string, kind cache.EntryKind) string
+	containerClient  *azblob.ContainerClient
+	storageAccount   string
+	container        string
+	prefix           string
+	v2mode           bool
+	uploadQueue      chan<- uploadReq
+	accessLogger     cache.Logger
+	errorLogger      cache.Logger
+	objectKey        func(hash string, kind cache.EntryKind) string
+	updateTimestamps bool
 }
 
 func (c *azBlobCache) Put(ctx context.Context, kind cache.EntryKind, hash string, size int64, rc io.ReadCloser) {
@@ -87,6 +89,10 @@ func (c *azBlobCache) Get(ctx context.Context, kind cache.EntryKind, hash string
 	}
 	cacheHits.Inc()
 
+	if c.updateTimestamps {
+		c.UpdateModificationTimestamp(ctx, key)
+	}
+
 	logResponse(c.accessLogger, "DOWNLOAD", c.storageAccount, c.container, key, err)
 
 	if kind == cache.CAS && c.v2mode {
@@ -137,6 +143,7 @@ func New(
 	prefix string,
 	creds azcore.TokenCredential,
 	sharedKey string,
+	UpdateTimestamps bool,
 	storageMode string, accessLogger cache.Logger,
 	errorLogger cache.Logger, numUploaders, maxQueuedUploads int,
 ) cache.Proxy {
@@ -149,7 +156,7 @@ func New(
 		if e != nil {
 			log.Fatalln(e)
 		}
-		serviceClient, e = azblob.NewServiceClientWithSharedKey(url, cred, nil)
+		serviceClient, err = azblob.NewServiceClientWithSharedKey(url, cred, nil)
 
 	} else {
 		serviceClient, err = azblob.NewServiceClient(url, creds, nil)
@@ -170,13 +177,14 @@ func New(
 	}
 
 	c := &azBlobCache{
-		containerClient: containerClient,
-		prefix:          prefix,
-		storageAccount:  storageAccount,
-		container:       containerName,
-		accessLogger:    accessLogger,
-		errorLogger:     errorLogger,
-		v2mode:          storageMode == "zstd",
+		containerClient:  containerClient,
+		prefix:           prefix,
+		storageAccount:   storageAccount,
+		container:        containerName,
+		accessLogger:     accessLogger,
+		errorLogger:      errorLogger,
+		v2mode:           storageMode == "zstd",
+		updateTimestamps: UpdateTimestamps,
 	}
 
 	if c.v2mode {
@@ -223,6 +231,18 @@ func (c *azBlobCache) uploadFile(item uploadReq) {
 	logResponse(c.accessLogger, "UPLOAD", c.storageAccount, c.container, key, err)
 }
 
+func (c *azBlobCache) UpdateModificationTimestamp(ctx context.Context, key string) {
+	client, err := c.containerClient.NewBlockBlobClient(key)
+	if err != nil {
+		logResponse(c.accessLogger, "UPDATE_TIMESTAMPS", c.storageAccount, c.container, key, err)
+	}
+	metadata := map[string]string{
+		"LastModified": time.Now().Format("1/2/2006, 03:05 PM"),
+	}
+	_, err = client.SetMetadata(ctx, metadata, nil)
+	logResponse(c.accessLogger, "UPDATE_TIMESTAMPS", c.storageAccount, c.container, key, err)
+}
+
 func objectKeyV2(prefix string, hash string, kind cache.EntryKind) string {
 	var baseKey string
 	if kind == cache.CAS {

config/azblob.go

@@ -11,15 +11,16 @@ import (
 )
 
 type AzBlobStorageConfig struct {
-	StorageAccount string `yaml:"storage_account"`
-	ContainerName  string `yaml:"container_name"`
-	Prefix         string `yaml:"prefix"`
-	AuthMethod     string `yaml:"auth_method"`
-	TenantID       string `yaml:"tenant_id"`
-	ClientID       string `yaml:"client_id"`
-	ClientSecret   string `yaml:"client_secret"`
-	CertPath       string `yaml:"cert_path"`
-	SharedKey      string `yaml:"shared_key"`
+	StorageAccount   string `yaml:"storage_account"`
+	ContainerName    string `yaml:"container_name"`
+	Prefix           string `yaml:"prefix"`
+	AuthMethod       string `yaml:"auth_method"`
+	TenantID         string `yaml:"tenant_id"`
+	ClientID         string `yaml:"client_id"`
+	ClientSecret     string `yaml:"client_secret"`
+	CertPath         string `yaml:"cert_path"`
+	SharedKey        string `yaml:"shared_key"`
+	UpdateTimestamps bool   `yaml:"update_timestamps"`
 }
 
 func (azblobc AzBlobStorageConfig) GetCredentials() (azcore.TokenCredential, error) {

config/config.go

@@ -463,15 +463,16 @@ func get(ctx *cli.Context) (*Config, error) {
 	var azblob *AzBlobStorageConfig
 	if ctx.String("azblob.tenant_id") != "" {
 		azblob = &AzBlobStorageConfig{
-			TenantID:       ctx.String("azblob.tenant_id"),
-			StorageAccount: ctx.String("azblob.storage_account"),
-			ContainerName:  ctx.String("azblob.container_name"),
-			Prefix:         ctx.String("azblob.prefix"),
-			AuthMethod:     ctx.String("azblob.auth_method"),
-			ClientID:       ctx.String("azblob.client_id"),
-			ClientSecret:   ctx.String("azblob.client_secret"),
-			CertPath:       ctx.String("azblob.cert_path"),
-			SharedKey:      ctx.String("azblob.shared_key"),
+			TenantID:         ctx.String("azblob.tenant_id"),
+			StorageAccount:   ctx.String("azblob.storage_account"),
+			ContainerName:    ctx.String("azblob.container_name"),
+			Prefix:           ctx.String("azblob.prefix"),
+			AuthMethod:       ctx.String("azblob.auth_method"),
+			ClientID:         ctx.String("azblob.client_id"),
+			ClientSecret:     ctx.String("azblob.client_secret"),
+			CertPath:         ctx.String("azblob.cert_path"),
+			SharedKey:        ctx.String("azblob.shared_key"),
+			UpdateTimestamps: ctx.Bool("azblob.update_timestamps"),
 		}
 	}
 

config/proxy.go

@@ -70,6 +70,7 @@ func (c *Config) setProxy() error {
 			c.AzBlobConfig.Prefix,
 			creds,
 			c.AzBlobConfig.SharedKey,
+			c.AzBlobConfig.UpdateTimestamps,
 			c.StorageMode, c.AccessLogger, c.ErrorLogger, c.NumUploaders, c.MaxQueuedUploads,
 		)
 		return nil

utils/flags/flags.go

@@ -308,6 +308,12 @@ func GetCliFlags() []cli.Flag {
 			Usage:   "The Azure blob storage object prefix to use when using azblob proxy backend.",
 			EnvVars: []string{"BAZEL_REMOTE_AZBLOB_PREFIX"},
 		},
+		&cli.BoolFlag{
+			Name:        "azblob.update_timestamps",
+			Usage:       "Whether to update timestamps of object on cache hit.",
+			DefaultText: "false",
+			EnvVars:     []string{"BAZEL_REMOTE_AZBLOB_UPDATE_TIMESTAMPS"},
+		},
 		&cli.StringFlag{
 			Name:    "azblob.auth_method",
 			Value:   "",