github.com/alibaba/sealer@v0.8.6-0.20220430115802-37a2bdaa8173/pkg/filesystem/filesystem.go (about)

     1  // Copyright © 2021 Alibaba Group Holding Ltd.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package filesystem
    16  
    17  import (
    18  	"fmt"
    19  
    20  	"github.com/alibaba/sealer/pkg/filesystem/cloudfilesystem"
    21  	"github.com/alibaba/sealer/pkg/filesystem/cloudimage"
    22  	"github.com/alibaba/sealer/pkg/image/store"
    23  	"github.com/alibaba/sealer/pkg/runtime"
    24  )
    25  
    26  // NewCloudImageMounter :mount and unmount cloud image.
    27  func NewCloudImageMounter() (cloudimage.Interface, error) {
    28  	is, err := store.NewDefaultImageStore()
    29  	if err != nil {
    30  		return nil, err
    31  	}
    32  	return cloudimage.NewCloudImageMounter(is)
    33  }
    34  
    35  // NewFilesystem :according to the Metadata file content to determine what kind of Filesystem will be load.
    36  func NewFilesystem(rootfs string) (cloudfilesystem.Interface, error) {
    37  	md, err := runtime.LoadMetadata(rootfs)
    38  	if err != nil {
    39  		return nil, fmt.Errorf("failed to load Metadata file to determine the filesystem type %v", err)
    40  	}
    41  
    42  	if md == nil || !md.NydusFlag {
    43  		return cloudfilesystem.NewOverlayFileSystem()
    44  	}
    45  
    46  	return cloudfilesystem.NewNydusFileSystem()
    47  }