github.com/alibaba/sealer@v0.8.6-0.20220430115802-37a2bdaa8173/pkg/infra/container/utils.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 container
    16  
    17  import (
    18  	"strconv"
    19  	"strings"
    20  
    21  	v1 "github.com/alibaba/sealer/types/api/v1"
    22  	"github.com/alibaba/sealer/utils"
    23  )
    24  
    25  func IsDockerAvailable() bool {
    26  	lines, err := utils.RunSimpleCmd("docker -v")
    27  	if err != nil || len(lines) != 1 {
    28  		return false
    29  	}
    30  	return strings.Contains(lines, "docker version")
    31  }
    32  
    33  func getDiff(host v1.Hosts) (int, []string, error) {
    34  	var num int
    35  	var iplist []string
    36  	count, err := strconv.Atoi(host.Count)
    37  	if err != nil {
    38  		return 0, nil, err
    39  	}
    40  	if count > len(host.IPList) {
    41  		//scale up
    42  		num = count - len(host.IPList)
    43  	}
    44  
    45  	if count < len(host.IPList) {
    46  		//scale down
    47  		iplist = host.IPList[count:]
    48  	}
    49  
    50  	return num, iplist, nil
    51  }