Merge pull request #95 from gadget-inc/cached_into_shared_dir

Cached into shared staging dir

Author: angelini

pkg/api/cached.go

@@ -2,8 +2,6 @@ package api
 
 import (
 	"context"
-	"crypto/rand"
-	"encoding/base64"
 	"errors"
 	"fmt"
 	"math"
@@ -41,9 +39,7 @@ type Cached struct {
 	Client      *client.Client
 	StagingPath string
 
-	// the current directory holding a fully formed downloaded cache
-	currentDir string
-	// the current version of the cache on disk at currentDir
+	// the current version of the cache on disk
 	currentVersion int64
 }
 
@@ -67,23 +63,18 @@ func (c *Cached) PopulateDiskCache(ctx context.Context, req *pb.PopulateDiskCach
 	return &pb.PopulateDiskCacheResponse{Version: version}, nil
 }
 
-// Fetch the cache into a spot in the staging dir
+// Fetch the cache into the staging dir
 func (c *Cached) Prepare(ctx context.Context) error {
 	start := time.Now()
-	folderName, err := randomString()
-	if err != nil {
-		return err
-	}
-	newDir := path.Join(c.StagingPath, folderName)
-	version, count, err := c.Client.GetCache(ctx, newDir)
+
+	version, count, err := c.Client.GetCache(ctx, c.StagingPath)
 	if err != nil {
 		return err
 	}
 
-	c.currentDir = newDir
 	c.currentVersion = version
 
-	logger.Info(ctx, "downloaded golden copy", key.Directory.Field(newDir), key.DurationMS.Field(time.Since(start)), key.Version.Field(version), key.Count.Field(int64(count)))
+	logger.Info(ctx, "downloaded golden copy", key.DurationMS.Field(time.Since(start)), key.Version.Field(version), key.Count.Field(int64(count)))
 	return nil
 }
 
@@ -109,7 +100,7 @@ func (c *Cached) GetPluginCapabilities(ctx context.Context, req *csi.GetPluginCa
 // Probe returns the health and readiness of the plugin
 func (c *Cached) Probe(ctx context.Context, req *csi.ProbeRequest) (*csi.ProbeResponse, error) {
 	ready := true
-	if c.currentDir == "" {
+	if c.currentVersion == 0 {
 		ready = false
 		logger.Warn(ctx, "csi probe failed as daemon hasn't prepared cache yet", key.Version.Field(c.currentVersion))
 	}
@@ -255,7 +246,7 @@ func (c *Cached) NodeGetVolumeStats(ctx context.Context, req *csi.NodeGetVolumeS
 // check if the destination exists, and if so, if its writable
 // hardlink the golden copy into this downstream's destination, creating it if need be
 func (c *Cached) writeCache(destination string) (int64, error) {
-	if c.currentDir == "" {
+	if c.currentVersion == 0 {
 		return -1, errors.New("no cache prepared, currentDir is nil")
 	}
 
@@ -274,7 +265,7 @@ func (c *Cached) writeCache(destination string) (int64, error) {
 		}
 	}
 
-	err = files.HardlinkDir(c.currentDir, destination)
+	err = files.HardlinkDir(c.StagingPath, destination)
 	if err != nil {
 		return -1, fmt.Errorf("failed to hardlink cache to destination %s: %v", destination, err)
 	}
@@ -301,12 +292,3 @@ func getFolderSize(path string) (int64, error) {
 	})
 	return totalSize, err
 }
-
-func randomString() (string, error) {
-	// Generate a secure random string for the temporary directory name
-	randBytes := make([]byte, 10) // Adjust the size of the byte slice as needed
-	if _, err := rand.Read(randBytes); err != nil {
-		return "", err
-	}
-	return base64.URLEncoding.EncodeToString(randBytes), nil
-}