Docker容器ID的生成方式
我想知道容器ID的生成方式,因此请提供执行docker run时提供容器ID的源代码?
回答:
这是docker守护程序创建容器的代码片段:
func (daemon *Daemon) newContainer(name string, config *runconfig.Config, imgID string) (*Container, error) { var (
id string
err error
)
id, name, err = daemon.generateIDAndName(name)
if err != nil {
return nil, err
}
…
base := daemon.newBaseContainer(id)
…
base.ExecDriver = daemon.execDriver.Name()
return &base, err
}
因此,创建ID和名称的逻辑是在generateIDAndName函数中:
func (daemon *Daemon) generateIDAndName(name string) (string, string, error) { var (
err error
id = stringid.GenerateNonCryptoID()
)
if name == "" {
if name, err = daemon.generateNewName(id); err != nil {
return "", "", err
}
return id, name, nil
}
if name, err = daemon.reserveName(id, name); err != nil {
return "", "", err
}
return id, name, nil
}
这是字符串源,具体方法是使用false作为输入参数的generateID:
func generateID(crypto bool) string { b := make([]byte, 32)
var r io.Reader = random.Reader
if crypto {
r = rand.Reader
}
for {
if _, err := io.ReadFull(r, b); err != nil {
panic(err) // This shouldn't happen
}
id := hex.EncodeToString(b)
// if we try to parse the truncated for as an int and we don't have
// an error then the value is all numberic and causes issues when
// used as a hostname. ref #3869
if _, err := strconv.ParseInt(TruncateID(id), 10, 64); err == nil {
continue
}
return id
}
}
正如你所看到的,该值是随机与此产生的随机
// Reader is a global, shared instance of a pseudorandom bytes generator.// It doesn't consume entropy.
var Reader io.Reader = &reader{rnd: Rand}
以上是 Docker容器ID的生成方式 的全部内容, 来源链接: utcz.com/qa/431166.html