github.com/mirantis/virtlet@v1.5.2-0.20191204181327-1659b8a48e9b/pkg/libvirttools/flexvolume_volumesource.go (about)

     1  /*
     2  Copyright 2017 Mirantis
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package libvirttools
    18  
    19  import (
    20  	"encoding/json"
    21  	"fmt"
    22  	"io/ioutil"
    23  	"os"
    24  	"path/filepath"
    25  
    26  	"github.com/golang/glog"
    27  
    28  	"github.com/Mirantis/virtlet/pkg/metadata/types"
    29  )
    30  
    31  const (
    32  	flexvolumeSubdir   = "volumes/virtlet~flexvolume_driver"
    33  	flexvolumeDataFile = "virtlet-flexvolume.json"
    34  )
    35  
    36  type flexvolumeSource func(volumeName, configPath string, config *types.VMConfig, owner volumeOwner) (VMVolume, error)
    37  
    38  var flexvolumeTypeMap = map[string]flexvolumeSource{}
    39  
    40  func addFlexvolumeSource(fvType string, source flexvolumeSource) {
    41  	flexvolumeTypeMap[fvType] = source
    42  }
    43  
    44  // ScanFlexVolumes returns VMVolume objects for Virtlet flexvolumes
    45  // mounted into the pod.
    46  func ScanFlexVolumes(config *types.VMConfig, owner volumeOwner) ([]VMVolume, error) {
    47  	dir := filepath.Join(owner.KubeletRootDir(), config.PodSandboxID, flexvolumeSubdir)
    48  	if _, err := os.Stat(dir); os.IsNotExist(err) {
    49  		glog.V(2).Infof("No flexvolumes to process for %q with uuid %q", config.Name, config.DomainUUID)
    50  		return nil, nil
    51  	} else if err != nil {
    52  		return nil, err
    53  	}
    54  
    55  	glog.V(2).Info("Processing flexvolumes for flexvolume_driver")
    56  	volDirItems, err := ioutil.ReadDir(dir)
    57  	if err != nil {
    58  		return nil, err
    59  	}
    60  
    61  	glog.V(2).Infof("Found flexvolumes definitions at %s:\n%#v", dir, volDirItems)
    62  	var vols []VMVolume
    63  	for _, fi := range volDirItems {
    64  		if !fi.IsDir() {
    65  			continue
    66  		}
    67  		dataFilePath := filepath.Join(dir, fi.Name(), flexvolumeDataFile)
    68  		content, err := ioutil.ReadFile(dataFilePath)
    69  		if err != nil {
    70  			if os.IsNotExist(err) {
    71  				continue
    72  			}
    73  			return nil, fmt.Errorf("error reading flexvolume config %q: %v", dataFilePath, err)
    74  		}
    75  		var msi map[string]interface{}
    76  		if err = json.Unmarshal(content, &msi); err != nil {
    77  			return nil, fmt.Errorf("error unmarshal flexvolume config %q: %v", dataFilePath, err)
    78  		}
    79  		fvType, _ := msi["type"].(string)
    80  		if fvType == "" {
    81  			return nil, fmt.Errorf("flexvolume config %q: need to specify 'type' (a string)", dataFilePath)
    82  		}
    83  		fvSource, found := flexvolumeTypeMap[fvType]
    84  		if !found {
    85  			return nil, fmt.Errorf("bad flexvolume config %q: bad type %q", dataFilePath, fvType)
    86  		}
    87  		vol, err := fvSource(fi.Name(), dataFilePath, config, owner)
    88  		if err != nil {
    89  			return nil, err
    90  		}
    91  		glog.V(3).Infof("Found flexvolume: %s", string(content))
    92  		vols = append(vols, vol)
    93  	}
    94  	return vols, nil
    95  }