[server] Streamline storage backend access, fix init error

server/internal/command/config.defaults.yml

@@ -7,8 +7,8 @@ db:
   nomigrate: false    # Do not auto-migrate schema (dev)
   trace: false        # Trace queries (dev)
 
-fs:
-  storage: storage
+storage:
+  location: storage
   
 user:
   password:

server/internal/core/resource_create.go

@@ -10,6 +10,7 @@ import (
 	"github.com/google/uuid"
 	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgtype"
+	"github.com/shroff/phylum/server/internal/storage"
 )
 
 type ResourceBindConflictResolution int32
@@ -276,7 +277,7 @@ func (f filesystem) createResourceVersion(id, versionID uuid.UUID, size int64, m
 		"size":        size,
 		"mime_type":   mimeType,
 		"sha256":      sha256,
-		"storage":     "_",
+		"storage":     storage.DefaultBackendName,
 	}
 	_, err := f.db.Exec(q, args)
 	return err

server/internal/core/version.go

@@ -28,8 +28,8 @@ func (v Version) OpenRead(start, length int) (io.ReadCloser, error) {
 	if v.Storage == "" {
 		return nil, errors.New("unknown storage backend")
 	}
-	if b := storage.GetBackend(v.Storage); b == nil {
-		return nil, errors.New("storage backend not found: " + v.Storage)
+	if b, err := storage.GetBackend(v.Storage); err != nil {
+		return nil, errors.New("failed to read " + v.ID.String() + ": " + err.Error())
 	} else {
 		return b.OpenRead(v.ID.String(), start, length)
 	}

server/internal/storage/storage.go

@@ -3,6 +3,7 @@ package storage
 import (
 	"encoding/json"
 	"errors"
+	"fmt"
 	"os"
 	"path"
 
@@ -12,6 +13,9 @@ import (
 )
 
 var Cfg Config
+
+const DefaultBackendName = "_"
+
 var defaultBackend LocalBackend
 var backends map[string]Backend
 
@@ -22,8 +26,15 @@ type BackendConfig struct {
 }
 
 func Initialize(db db.Handler) error {
-	if err := os.Chmod(Cfg.Location, 0700); err != nil {
-		return errors.New("failed to set permissions: " + err.Error())
+	if err := os.MkdirAll(Cfg.Location, 0700); err != nil {
+		return errors.New("failed to create storage location(" + Cfg.Location + "): " + err.Error())
+	} else {
+		if stat, err := os.Stat(Cfg.Location); err != nil {
+			return errors.New("failed to stat storage location(" + Cfg.Location + "): " + err.Error())
+		} else if stat.Mode()&0xfff != 0700 {
+			return errors.New("storage location does not have correct permissions (0700): " + fmt.Sprintf("%o", stat.Mode()&0xfff))
+		}
+
 	}
 	if restoredBackends, err := restoreBackends(db); err != nil {
 		return errors.New("failed to restore backends: " + err.Error())
@@ -42,11 +53,15 @@ func DefaultBackend() LocalBackend {
 	return defaultBackend
 }
 
-func GetBackend(name string) Backend {
-	if name == "_" {
-		return defaultBackend
+func GetBackend(name string) (Backend, error) {
+	if name == DefaultBackendName {
+		return defaultBackend, nil
+	}
+	if b, ok := backends[name]; !ok {
+		return nil, errors.New("no storage backend named \"" + name + "\"")
+	} else {
+		return b, nil
 	}
-	return backends[name]
 }
 
 func ListBackends() map[string]Backend {