// RunDaemon creates the docker container, pulling images if necessary, starts
// the container and returns the container information. It does not wait for
// the container to exit.
func RunDaemon(client dockerclient.Client, conf *dockerclient.ContainerConfig, name string) (*dockerclient.ContainerInfo, error) {
// attempts to create the contianer
id, err := client.CreateContainer(conf, name)
if err != nil {
// and pull the image and re-create if that fails
err = client.PullImage(conf.Image, nil)
if err != nil {
return nil, err
}
id, err = client.CreateContainer(conf, name)
if err != nil {
client.RemoveContainer(id, true, true)
return nil, err
}
}
// fetches the container information
info, err := client.InspectContainer(id)
if err != nil {
client.RemoveContainer(id, true, true)
return nil, err
}
// starts the container
err = client.StartContainer(id, &conf.HostConfig)
if err != nil {
client.RemoveContainer(id, true, true)
return nil, err
}
return info, err
}
// BindingAddr provides the address for the container and binding.
func BindingAddr(d dockerclient.Client, name, binding string) (string, error) {
ci, err := d.InspectContainer(name)
if err != nil {
return "", stackerr.Wrap(err)
}
ip, err := dockerIP(d)
if err != nil {
return "", err
}
hostname, err := etcHostsName(ip)
if err != nil {
return "", err
}
if hostname == "" {
hostname = ip.String()
}
addr := fmt.Sprintf(
"%s:%s",
hostname,
ci.NetworkSettings.Ports[binding][0].HostPort,
)
return addr, nil
}
// Wait blocks until the named container exits, returning the exit information.
func Wait(client dockerclient.Client, name string) (*dockerclient.ContainerInfo, error) {
defer func() {
client.StopContainer(name, 5)
client.KillContainer(name, "9")
}()
for attempts := 0; attempts < 5; attempts++ {
done := client.Wait(name)
<-done
info, err := client.InspectContainer(name)
if err != nil {
return nil, err
}
if !info.State.Running {
return info, nil
}
log.Debugf("attempting to resume waiting after %d attempts.\n", attempts)
}
return nil, errors.New("reached maximum wait attempts")
}
func Run(client dockerclient.Client, conf *dockerclient.ContainerConfig, auth *dockerclient.AuthConfig, pull bool, outw, errw io.Writer) (*dockerclient.ContainerInfo, error) {
if outw == nil {
outw = os.Stdout
}
if errw == nil {
errw = os.Stdout
}
// fetches the container information.
info, err := Start(client, conf, auth, pull)
if err != nil {
return nil, err
}
// ensures the container is always stopped
// and ready to be removed.
defer func() {
client.StopContainer(info.Id, 5)
client.KillContainer(info.Id, "9")
}()
// channel listening for errors while the
// container is running async.
errc := make(chan error, 1)
infoc := make(chan *dockerclient.ContainerInfo, 1)
go func() {
// blocks and waits for the container to finish
// by streaming the logs (to /dev/null). Ideally
// we could use the `wait` function instead
rc, err := client.ContainerLogs(info.Id, logOptsTail)
if err != nil {
log.Errorf("Error tailing %s. %s\n", conf.Image, err)
errc <- err
return
}
defer rc.Close()
StdCopy(outw, errw, rc)
// fetches the container information
info, err := client.InspectContainer(info.Id)
if err != nil {
log.Errorf("Error getting exit code for %s. %s\n", conf.Image, err)
errc <- err
return
}
infoc <- info
}()
select {
case info := <-infoc:
return info, nil
case err := <-errc:
return info, err
}
}
func Start(client dockerclient.Client, conf *dockerclient.ContainerConfig, auth *dockerclient.AuthConfig, pull bool) (*dockerclient.ContainerInfo, error) {
// force-pull the image if specified.
if pull {
log.Printf("Pulling image %s", conf.Image)
client.PullImage(conf.Image, auth)
}
// attempts to create the contianer
id, err := client.CreateContainer(conf, "", auth)
if err != nil {
log.Printf("Pulling image %s", conf.Image)
// and pull the image and re-create if that fails
err = client.PullImage(conf.Image, auth)
if err != nil {
log.Errorf("Error pulling %s. %s\n", conf.Image, err)
return nil, err
}
id, err = client.CreateContainer(conf, "", auth)
if err != nil {
log.Errorf("Error creating %s. %s\n", conf.Image, err)
client.RemoveContainer(id, true, true)
return nil, err
}
}
// fetches the container information
info, err := client.InspectContainer(id)
if err != nil {
log.Errorf("Error inspecting %s. %s\n", conf.Image, err)
client.RemoveContainer(id, true, true)
return nil, err
}
// starts the container
err = client.StartContainer(id, &conf.HostConfig)
if err != nil {
log.Errorf("Error starting %s. %s\n", conf.Image, err)
}
return info, err
}
// Wait blocks until the named container exits, returning the exit information.
func Wait(client dockerclient.Client, name string) (*dockerclient.ContainerInfo, error) {
defer func() {
client.StopContainer(name, 5)
client.KillContainer(name, "9")
}()
errc := make(chan error, 1)
infoc := make(chan *dockerclient.ContainerInfo, 1)
go func() {
// blocks and waits for the container to finish
// by streaming the logs (to /dev/null). Ideally
// we could use the `wait` function instead
rc, err := client.ContainerLogs(name, LogOptsTail)
if err != nil {
errc <- err
return
}
io.Copy(ioutil.Discard, rc)
rc.Close()
info, err := client.InspectContainer(name)
if err != nil {
errc <- err
return
}
infoc <- info
}()
select {
case info := <-infoc:
return info, nil
case err := <-errc:
return nil, err
}
}
// Inspect a container
func Inspect(docker dockerclient.Client, id string) *dockerclient.ContainerInfo {
info, _ := docker.InspectContainer(id)
log.Println(info)
return info
}
func Run(client dockerclient.Client, conf *dockerclient.ContainerConfig, auth *dockerclient.AuthConfig, pull bool, outw, errw io.Writer) (*dockerclient.ContainerInfo, error) {
if outw == nil {
outw = os.Stdout
}
if errw == nil {
errw = os.Stdout
}
// fetches the container information.
info, err := Start(client, conf, auth, pull)
if err != nil {
return nil, err
}
// ensures the container is always stopped
// and ready to be removed.
defer func() {
client.StopContainer(info.Id, 5)
client.KillContainer(info.Id, "9")
}()
// channel listening for errors while the
// container is running async.
errc := make(chan error, 1)
infoc := make(chan *dockerclient.ContainerInfo, 1)
go func() {
// options to fetch the stdout and stderr logs
// by tailing the output.
logOptsTail := &dockerclient.LogOptions{
Follow: true,
Stdout: true,
Stderr: true,
}
// It's possible that the docker logs endpoint returns before the container
// is done, we'll naively resume up to 5 times if when the logs unblocks
// the container is still reported to be running.
for attempts := 0; attempts < 5; attempts++ {
if attempts > 0 {
// When resuming the stream, only grab the last line when starting
// the tailing.
logOptsTail.Tail = 1
}
// blocks and waits for the container to finish
// by streaming the logs (to /dev/null). Ideally
// we could use the `wait` function instead
rc, err := client.ContainerLogs(info.Id, logOptsTail)
if err != nil {
log.Errorf("Error tailing %s. %s\n", conf.Image, err)
errc <- err
return
}
defer rc.Close()
_, err = StdCopy(outw, errw, rc)
if err != nil {
log.Errorf("Error streaming docker logs for %s. %s\n", conf.Image, err)
errc <- err
return
}
// fetches the container information
info, err := client.InspectContainer(info.Id)
if err != nil {
log.Errorf("Error getting exit code for %s. %s\n", conf.Image, err)
errc <- err
return
}
if !info.State.Running {
// The container is no longer running, there should be no more logs to tail.
infoc <- info
return
}
log.Debugf("Attempting to resume log tailing after %d attempts.\n", attempts)
}
errc <- errors.New("Maximum number of attempts made while tailing logs.")
}()
select {
case info := <-infoc:
return info, nil
case err := <-errc:
return info, err
}
}
func Run(client dockerclient.Client, conf *dockerclient.ContainerConfig, auth *dockerclient.AuthConfig, pull bool, outw, errw io.Writer) (*dockerclient.ContainerInfo, error) {
if outw == nil {
outw = os.Stdout
}
if errw == nil {
errw = os.Stdout
}
// fetches the container information.
info, err := Start(client, conf, auth, pull)
if err != nil {
return nil, err
}
// ensures the container is always stopped
// and ready to be removed.
defer func() {
client.StopContainer(info.Id, 5)
client.KillContainer(info.Id, "9")
}()
// channel listening for errors while the
// container is running async.
errc := make(chan error, 1)
infoc := make(chan *dockerclient.ContainerInfo, 1)
go func() {
// It's possible that the docker logs endpoint returns before the container
// is done, we'll naively resume up to 5 times if when the logs unblocks
// the container is still reported to be running.
var total int64
for attempts := 0; attempts < 5; attempts++ {
// blocks and waits for the container to finish
// by streaming the logs (to /dev/null). Ideally
// we could use the `wait` function instead
rc, err := client.ContainerLogs(info.Id, logOptsTail)
if err != nil {
log.Errorf("Error tailing %s. %s\n", conf.Image, err)
errc <- err
return
}
defer rc.Close()
if total != 0 {
// Discard off the total bytes we've received so far.
// io.LimitReader returns EOF once it has read the specified number
// of bytes as per https://golang.org/pkg/io/#LimitReader.
r := io.LimitReader(rc, total)
_, err := io.Copy(ioutil.Discard, r)
if err != nil && err != io.EOF {
log.Errorf("Error resuming streaming docker logs for %s. %s\n", conf.Image, err)
errc <- err
return
}
}
rcv, err := StdCopy(outw, errw, rc)
if err != nil {
log.Errorf("Error streaming docker logs for %s. %s\n", conf.Image, err)
errc <- err
return
}
// fetches the container information
info, err := client.InspectContainer(info.Id)
if err != nil {
log.Errorf("Error getting exit code for %s. %s\n", conf.Image, err)
errc <- err
return
}
if !info.State.Running {
// The container is no longer running, there should be no more logs to tail.
infoc <- info
return
}
total += rcv
log.Debugf("Attempting to resume log tailing after receiving %d bytes. Attempts %d.\n", total, attempts)
}
errc <- errors.New("Maximum number of attempts made while tailing logs.")
}()
select {
case info := <-infoc:
return info, nil
case err := <-errc:
return info, err
}
}