bugfix: pouch pull should handle space input as an error

Signed-off-by: xiechengsheng <XIE1995@whut.edu.cn>

cli/pull.go

@@ -204,7 +204,11 @@ func pullMissingImage(ctx context.Context, apiClient client.CommonAPIClient, ima
 		}
 	}
 
-	namedRef, _ := reference.Parse(image)
+	namedRef, err := reference.Parse(image)
+	if err != nil {
+		return err
+	}
+
 	namedRef = reference.TrimTagForDigest(reference.WithDefaultTagIfMissing(namedRef))
 
 	var name, tag string

pkg/reference/parse.go

@@ -7,17 +7,14 @@ import (
 )
 
 var (
-	// ErrInvalid is used to return error if reference is invalid
-	ErrInvalid = errors.New("invalid reference")
-
 	// defaultTag is latest if there is no tag
 	defaultTag = "latest"
 )
 
 // Parse parses ref into reference.Named.
 func Parse(ref string) (Named, error) {
 	if ok := regRef.MatchString(ref); !ok {
-		return nil, ErrInvalid
+		return nil, errors.New("invalid reference: " + ref)
 	}
 
 	name, tag, digStr := splitReference(ref)