engine: resources: Modernize the docker resources

They made the assumption that there would be a based docker service
installed at Init which could not be guaranteed. Also use the internal
metaparameter timeout feature instead of private counters.
This commit is contained in:
James Shubin
2025-03-12 02:13:47 -04:00
parent a6057319a9
commit 05306e3729
2 changed files with 72 additions and 83 deletions

View File

@@ -37,7 +37,6 @@ import (
"io"
"regexp"
"strings"
"time"
"github.com/purpleidea/mgmt/engine"
"github.com/purpleidea/mgmt/engine/traits"
@@ -47,8 +46,8 @@ import (
"github.com/docker/docker/api/types"
"github.com/docker/docker/api/types/container"
"github.com/docker/docker/api/types/filters"
"github.com/docker/docker/api/types/image"
"github.com/docker/docker/client"
dockerImage "github.com/docker/docker/api/types/image"
dockerClient "github.com/docker/docker/client"
"github.com/docker/go-connections/nat"
)
@@ -59,13 +58,6 @@ const (
ContainerStopped = "stopped"
// ContainerRemoved is the removed container state.
ContainerRemoved = "removed"
// initCtxTimeout is the length of time, in seconds, before requests are
// cancelled in Init.
initCtxTimeout = 20
// checkApplyCtxTimeout is the length of time, in seconds, before
// requests are cancelled in CheckApply.
checkApplyCtxTimeout = 120
)
func init() {
@@ -100,9 +92,9 @@ type DockerContainerRes struct {
// image is incorrect.
Force bool `lang:"force" yaml:"force"`
client *client.Client // docker api client
init *engine.Init
client *dockerClient.Client // docker api client
}
// Default returns some sensible defaults for this resource.
@@ -159,40 +151,27 @@ func (obj *DockerContainerRes) Validate() error {
// Init runs some startup code for this resource.
func (obj *DockerContainerRes) Init(init *engine.Init) error {
var err error
obj.init = init // save for later
ctx, cancel := context.WithTimeout(context.Background(), initCtxTimeout*time.Second)
defer cancel()
// Initialize the docker client.
obj.client, err = client.NewClientWithOpts(client.WithVersion(obj.APIVersion))
if err != nil {
return errwrap.Wrapf(err, "error creating docker client")
}
// Validate the image.
resp, err := obj.client.ImageSearch(ctx, obj.Image, types.ImageSearchOptions{Limit: 1})
if err != nil {
return errwrap.Wrapf(err, "error searching for image")
}
if len(resp) == 0 {
return fmt.Errorf("image: %s not found", obj.Image)
}
return nil
}
// Cleanup is run by the engine to clean up after the resource is done.
func (obj *DockerContainerRes) Cleanup() error {
return obj.client.Close() // close the docker client
return nil
}
// Watch is the primary listener for this resource and it outputs events.
func (obj *DockerContainerRes) Watch(ctx context.Context) error {
innerCtx, cancel := context.WithCancel(context.Background())
defer cancel()
eventChan, errChan := obj.client.Events(innerCtx, types.EventsOptions{})
// Initialize the docker client.
client, err := dockerClient.NewClientWithOpts(dockerClient.WithVersion(obj.APIVersion))
if err != nil {
return errwrap.Wrapf(err, "error creating docker client")
}
defer client.Close()
eventChan, errChan := client.Events(ctx, types.EventsOptions{})
obj.init.Running() // when started, notify engine that we're running
@@ -230,9 +209,23 @@ func (obj *DockerContainerRes) Watch(ctx context.Context) error {
func (obj *DockerContainerRes) CheckApply(ctx context.Context, apply bool) (bool, error) {
var id string
var destroy bool
var err error
ctx, cancel := context.WithTimeout(ctx, checkApplyCtxTimeout*time.Second)
defer cancel()
// Initialize the docker client.
obj.client, err = dockerClient.NewClientWithOpts(dockerClient.WithVersion(obj.APIVersion))
if err != nil {
return false, errwrap.Wrapf(err, "error creating docker client")
}
defer obj.client.Close() // close the docker client
// Validate the image.
resp, err := obj.client.ImageSearch(ctx, obj.Image, types.ImageSearchOptions{Limit: 1})
if err != nil {
return false, errwrap.Wrapf(err, "error searching for image")
}
if len(resp) == 0 {
return false, fmt.Errorf("image: %s not found", obj.Image)
}
// List any container whose name matches this resource.
opts := container.ListOptions{
@@ -295,7 +288,7 @@ func (obj *DockerContainerRes) CheckApply(ctx context.Context, apply bool) (bool
if len(containerList) == 0 { // no container was found
// Download the specified image if it doesn't exist locally.
p, err := obj.client.ImagePull(ctx, obj.Image, image.PullOptions{})
p, err := obj.client.ImagePull(ctx, obj.Image, dockerImage.PullOptions{})
if err != nil {
return false, errwrap.Wrapf(err, "error pulling image")
}
@@ -340,6 +333,7 @@ func (obj *DockerContainerRes) CheckApply(ctx context.Context, apply bool) (bool
// containerStart starts the specified container, and waits for it to start.
func (obj *DockerContainerRes) containerStart(ctx context.Context, id string, opts container.StartOptions) error {
obj.init.Logf("starting...")
// Get an events channel for the container we're about to start.
eventOpts := types.EventsOptions{
Filters: filters.NewArgs(filters.KeyValuePair{Key: "container", Value: id}),
@@ -350,6 +344,7 @@ func (obj *DockerContainerRes) containerStart(ctx context.Context, id string, op
return errwrap.Wrapf(err, "error starting container")
}
// Wait for a message on eventChan that says the container has started.
// TODO: Should we add ctx here or does cancelling above guarantee exit?
select {
case event := <-eventCh:
if event.Status != "start" {
@@ -363,11 +358,13 @@ func (obj *DockerContainerRes) containerStart(ctx context.Context, id string, op
// containerStop stops the specified container and waits for it to stop.
func (obj *DockerContainerRes) containerStop(ctx context.Context, id string, timeout *int) error {
obj.init.Logf("stopping...")
ch, errCh := obj.client.ContainerWait(ctx, id, container.WaitConditionNotRunning)
stopOpts := container.StopOptions{
Timeout: timeout,
}
obj.client.ContainerStop(ctx, id, stopOpts)
// TODO: Should we add ctx here or does cancelling above guarantee exit?
select {
case <-ch:
case err := <-errCh:
@@ -379,8 +376,10 @@ func (obj *DockerContainerRes) containerStop(ctx context.Context, id string, tim
// containerRemove removes the specified container and waits for it to be
// removed.
func (obj *DockerContainerRes) containerRemove(ctx context.Context, id string, opts container.RemoveOptions) error {
obj.init.Logf("removing...")
ch, errCh := obj.client.ContainerWait(ctx, id, container.WaitConditionRemoved)
obj.client.ContainerRemove(ctx, id, opts)
// TODO: Should we add ctx here or does cancelling above guarantee exit?
select {
case <-ch:
case err := <-errCh:

View File

@@ -37,27 +37,17 @@ import (
"io"
"regexp"
"strings"
"time"
"github.com/purpleidea/mgmt/engine"
"github.com/purpleidea/mgmt/engine/traits"
"github.com/docker/docker/api/types"
"github.com/docker/docker/api/types/filters"
"github.com/docker/docker/api/types/image"
"github.com/docker/docker/client"
dockerImage "github.com/docker/docker/api/types/image"
dockerClient "github.com/docker/docker/client"
errwrap "github.com/pkg/errors"
)
const (
// dockerImageInitCtxTimeout is the length of time, in seconds, before
// requests are cancelled in Init.
dockerImageInitCtxTimeout = 20
// dockerImageCheckApplyCtxTimeout is the length of time, in seconds,
// before requests are cancelled in CheckApply.
dockerImageCheckApplyCtxTimeout = 120
)
func init() {
engine.RegisterResource("docker:image", func() engine.Res { return &DockerImageRes{} })
}
@@ -75,9 +65,6 @@ type DockerImageRes struct {
// version.
APIVersion string `lang:"apiversion" yaml:"apiversion"`
image string // full image:tag format
client *client.Client // docker api client
init *engine.Init
}
@@ -113,43 +100,27 @@ func (obj *DockerImageRes) Validate() error {
// Init runs some startup code for this resource.
func (obj *DockerImageRes) Init(init *engine.Init) error {
var err error
obj.init = init // save for later
// Save the full image name and tag.
obj.image = dockerImageNameTag(obj.Name())
ctx, cancel := context.WithTimeout(context.Background(), dockerImageInitCtxTimeout*time.Second)
defer cancel()
// Initialize the docker client.
obj.client, err = client.NewClientWithOpts(client.WithVersion(obj.APIVersion))
if err != nil {
return errwrap.Wrapf(err, "error creating docker client")
}
// Validate the image.
resp, err := obj.client.ImageSearch(ctx, obj.image, types.ImageSearchOptions{Limit: 1})
if err != nil {
return errwrap.Wrapf(err, "error searching for image")
}
if len(resp) == 0 {
return fmt.Errorf("image: %s not found", obj.image)
}
return nil
}
// Cleanup is run by the engine to clean up after the resource is done.
func (obj *DockerImageRes) Cleanup() error {
return obj.client.Close() // close the docker client
return nil
}
// Watch is the primary listener for this resource and it outputs events.
func (obj *DockerImageRes) Watch(ctx context.Context) error {
innerCtx, cancel := context.WithCancel(context.Background())
defer cancel()
eventChan, errChan := obj.client.Events(innerCtx, types.EventsOptions{})
// Initialize the docker client.
client, err := dockerClient.NewClientWithOpts(dockerClient.WithVersion(obj.APIVersion))
if err != nil {
return errwrap.Wrapf(err, "error creating docker client")
}
defer client.Close()
eventChan, errChan := client.Events(ctx, types.EventsOptions{})
// notify engine that we're running
obj.init.Running()
@@ -186,11 +157,28 @@ func (obj *DockerImageRes) Watch(ctx context.Context) error {
// CheckApply method for Docker resource.
func (obj *DockerImageRes) CheckApply(ctx context.Context, apply bool) (checkOK bool, err error) {
ctx, cancel := context.WithTimeout(ctx, dockerImageCheckApplyCtxTimeout*time.Second)
defer cancel()
s, err := obj.client.ImageList(ctx, image.ListOptions{
Filters: filters.NewArgs(filters.Arg("reference", obj.image)),
// Save the full image name and tag.
image := dockerImageNameTag(obj.Name())
// Initialize the docker client.
client, err := dockerClient.NewClientWithOpts(dockerClient.WithVersion(obj.APIVersion))
if err != nil {
return false, errwrap.Wrapf(err, "error creating docker client")
}
defer client.Close()
// Validate the image.
resp, err := client.ImageSearch(ctx, image, types.ImageSearchOptions{Limit: 1})
if err != nil {
return false, errwrap.Wrapf(err, "error searching for image")
}
if len(resp) == 0 {
return false, fmt.Errorf("image: %s not found", image)
}
s, err := client.ImageList(ctx, dockerImage.ListOptions{
Filters: filters.NewArgs(filters.Arg("reference", image)),
})
if err != nil {
return false, errwrap.Wrapf(err, "error listing images")
@@ -211,15 +199,17 @@ func (obj *DockerImageRes) CheckApply(ctx context.Context, apply bool) (checkOK
}
if obj.State == "absent" {
obj.init.Logf("removing...")
// TODO: force? prune children?
if _, err := obj.client.ImageRemove(ctx, obj.image, image.RemoveOptions{}); err != nil {
if _, err := client.ImageRemove(ctx, image, dockerImage.RemoveOptions{}); err != nil {
return false, errwrap.Wrapf(err, "error removing image")
}
return false, nil
}
// pull the image
p, err := obj.client.ImagePull(ctx, obj.image, image.PullOptions{})
obj.init.Logf("pulling...")
p, err := client.ImagePull(ctx, image, dockerImage.PullOptions{})
if err != nil {
return false, errwrap.Wrapf(err, "error pulling image")
}