// EnsureDocker attempts to connect to the Docker daemon defined by the helper,
// and if it is unable to it will print a warning.
func (c *NodeConfig) EnsureDocker(docker *dockerutil.Helper) {
dockerClient, dockerAddr := docker.GetClientOrExit()
if err := dockerClient.Ping(); err != nil {
c.HandleDockerError(fmt.Sprintf("Docker could not be reached at %s. Docker must be installed and running to start containers.\n%v", dockerAddr, err))
return
}
glog.Infof("Connecting to Docker at %s", dockerAddr)
env, err := dockerClient.Version()
if err != nil {
c.HandleDockerError(fmt.Sprintf("Unable to check for Docker server version.\n%v", err))
return
}
serverVersionString := env.Get("ApiVersion")
serverVersion, err := dockerclient.NewAPIVersion(serverVersionString)
if err != nil {
c.HandleDockerError(fmt.Sprintf("Unable to determine Docker server version from %q.\n%v", serverVersionString, err))
return
}
minimumPullByIDVersion, err := dockerclient.NewAPIVersion(minimumDockerAPIVersionWithPullByID)
if err != nil {
c.HandleDockerError(fmt.Sprintf("Unable to check for Docker server version.\n%v", err))
return
}
if serverVersion.LessThan(minimumPullByIDVersion) {
c.HandleDockerError(fmt.Sprintf("Docker 1.6 or later (server API version 1.18 or later) required."))
return
}
c.DockerClient = dockerClient
}
