Code refactor, separate discovery from manager

pkg/containers/discovery.go

@@ -0,0 +1,78 @@
+package containers
+
+import (
+	"context"
+	"strings"
+	"traefik-lazyload/pkg/config"
+
+	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/api/types/filters"
+	"github.com/docker/docker/client"
+)
+
+type Discovery struct {
+	client *client.Client
+}
+
+func NewDiscovery(client *client.Client) *Discovery {
+	return &Discovery{client}
+}
+
+// Return all containers that qualify to be load-managed (eg. have the tag)
+func (s *Discovery) QualifyingContainers(ctx context.Context) ([]Wrapper, error) {
+	return s.FindAllLazyload(ctx, true)
+}
+
+func (s *Discovery) ProviderContainers(ctx context.Context) ([]Wrapper, error) {
+	filters := filters.NewArgs()
+	filters.Add("label", config.SubLabel("provides"))
+
+	return wrapListResult(s.client.ContainerList(ctx, types.ContainerListOptions{
+		Filters: filters,
+		All:     true,
+	}))
+}
+
+func (s *Discovery) FindAllLazyload(ctx context.Context, includeStopped bool) ([]Wrapper, error) {
+	filters := filters.NewArgs()
+	filters.Add("label", config.Model.LabelPrefix)
+
+	return wrapListResult(s.client.ContainerList(ctx, types.ContainerListOptions{
+		All:     includeStopped,
+		Filters: filters,
+	}))
+}
+
+func (s *Discovery) FindContainerByHostname(ctx context.Context, hostname string) (*Wrapper, error) {
+	containers, err := s.FindAllLazyload(ctx, true)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, c := range containers {
+		if hostStr, ok := c.Config("hosts"); ok {
+			hosts := strings.Split(hostStr, ",")
+			if strSliceContains(hosts, hostname) {
+				return &c, nil
+			}
+		} else {
+			// If not defined explicitely, infer from traefik route
+			for k, v := range c.Labels {
+				if strings.Contains(k, "traefik.http.routers.") && strings.Contains(v, hostname) { // TODO: More complex
+					return &c, nil
+				}
+			}
+		}
+	}
+
+	return nil, ErrNotFound
+}
+
+func (s *Discovery) FindDepProvider(ctx context.Context, name string) ([]Wrapper, error) {
+	filters := filters.NewArgs()
+	filters.Add("label", config.SubLabel("provides")+"="+name)
+	return wrapListResult(s.client.ContainerList(ctx, types.ContainerListOptions{
+		Filters: filters,
+		All:     true,
+	}))
+}

pkg/containers/errors.go

@@ -1,4 +1,4 @@
-package service
+package containers
 
 import "errors"
 

pkg/containers/util.go

@@ -0,0 +1,10 @@
+package containers
+
+func strSliceContains(slice []string, s string) bool {
+	for _, item := range slice {
+		if item == s {
+			return true
+		}
+	}
+	return false
+}

pkg/containers/wrapper.go

@@ -0,0 +1,120 @@
+package containers
+
+import (
+	"fmt"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+	"traefik-lazyload/pkg/config"
+
+	"github.com/docker/docker/api/types"
+	"github.com/sirupsen/logrus"
+)
+
+// Wrapper for container results that opaques and adds some methods to that data
+type Wrapper struct {
+	types.Container
+}
+
+// Human-consumable name + ID
+func (s *Wrapper) NameID() string {
+	var name string
+	if len(s.Names) > 0 {
+		name = strings.TrimPrefix(s.Names[0], "/")
+	} else {
+		name = s.Image
+	}
+	return fmt.Sprintf("%s (%s)", name, s.ShortId())
+}
+
+// char-len capped ID
+func (s *Wrapper) ShortId() string {
+	const SLEN = 8
+	if len(s.ID) <= SLEN {
+		return s.ID
+	}
+	return s.ID[:SLEN]
+}
+
+// Returns config labels with the prefix trimmed
+func (s *Wrapper) ConfigLabels() map[string]string {
+	var matchString = config.Model.LabelPrefix + "."
+
+	ret := make(map[string]string)
+	for k, v := range s.Labels {
+		if strings.HasPrefix(k, matchString) {
+			ret[k[len(matchString):]] = v
+		}
+	}
+
+	return ret
+}
+
+func (s *Wrapper) Config(sublabel string) (string, bool) {
+	ret, ok := s.Labels[config.SubLabel(sublabel)]
+	return ret, ok
+}
+
+func (s *Wrapper) ConfigOrDefault(sublabel, dflt string) (string, bool) {
+	if val, ok := s.Config(sublabel); ok {
+		return val, true
+	}
+	return dflt, false
+}
+
+func (s *Wrapper) ConfigCSV(sublabel string, dflt []string) ([]string, bool) {
+	if val, ok := s.Config(sublabel); ok {
+		return strings.Split(val, ","), true
+	}
+	return dflt, false
+}
+
+func (s *Wrapper) ConfigInt(sublabel string, dflt int) (int, bool) {
+	val, ok := s.Config(sublabel)
+	if !ok {
+		return dflt, false
+	}
+
+	if ival, err := strconv.Atoi(val); err != nil {
+		logrus.Warnf("Unable to parse %s on %s: %v. Using default of %d", sublabel, s.NameID(), err, dflt)
+		return dflt, false
+	} else {
+		return ival, true
+	}
+}
+
+func (s *Wrapper) ConfigDuration(sublabel string, dflt time.Duration) (time.Duration, bool) {
+	val, ok := s.Config(sublabel)
+	if !ok {
+		return dflt, false
+	}
+
+	if dur, err := time.ParseDuration(val); err != nil {
+		logrus.Warnf("Unable to parse %s on %s: %v. Using default of %s", sublabel, s.NameID(), err, dflt.String())
+		return dflt, false
+	} else {
+		return dur, true
+	}
+}
+
+// true if state is running
+func (s *Wrapper) IsRunning() bool {
+	return s.State == "running"
+}
+
+// Wrap a container set
+func wrapContainers(cts ...types.Container) []Wrapper {
+	ret := make([]Wrapper, len(cts))
+	for i, c := range cts {
+		ret[i] = Wrapper{c}
+	}
+	sort.Slice(ret, func(i, j int) bool {
+		return ret[i].NameID() < ret[j].NameID()
+	})
+	return ret
+}
+
+func wrapListResult(cts []types.Container, err error) ([]Wrapper, error) {
+	return wrapContainers(cts...), err
+}

pkg/service/container.go

@@ -1,12 +1,9 @@
 package service
 
 import (
-	"sort"
-	"strings"
 	"time"
 	"traefik-lazyload/pkg/config"
-
-	"github.com/docker/docker/api/types"
+	"traefik-lazyload/pkg/containers"
 )
 
 type containerSettings struct {
@@ -26,21 +23,21 @@ type ContainerState struct {
 	pinned             bool // Don't remove, even if not started
 }
 
-func newStateFromContainer(ct *types.Container) *ContainerState {
+func newStateFromContainer(ct *containers.Wrapper) *ContainerState {
 	return &ContainerState{
-		name:              containerShort(ct),
+		name:              ct.NameID(),
 		containerSettings: extractContainerLabels(ct),
 		lastActivity:      time.Now(),
 		started:           time.Now(),
 	}
 }
 
-func extractContainerLabels(ct *types.Container) (target containerSettings) {
-	target.stopDelay, _ = labelOrDefaultDuration(ct, "stopdelay", config.Model.StopDelay)
-	target.waitForCode, _ = labelOrDefaultInt(ct, "waitforcode", 200)
-	target.waitForPath, _ = labelOrDefault(ct, "waitforpath", "/")
-	target.waitForMethod, _ = labelOrDefault(ct, "waitformethod", "HEAD")
-	target.needs, _ = labelOrDefaultArr(ct, "needs")
+func extractContainerLabels(ct *containers.Wrapper) (target containerSettings) {
+	target.stopDelay, _ = ct.ConfigDuration("stopdelay", config.Model.StopDelay)
+	target.waitForCode, _ = ct.ConfigInt("waitforcode", 200)
+	target.waitForPath, _ = ct.ConfigOrDefault("waitforpath", "/")
+	target.waitForMethod, _ = ct.ConfigOrDefault("waitformethod", "HEAD")
+	target.needs, _ = ct.ConfigCSV("needs", nil)
 	return
 }
 
@@ -52,7 +49,7 @@ func (s *ContainerState) LastActive() time.Time {
 	return s.lastActivity
 }
 
-func (s *ContainerState) LastActiveAge() string {
+func (s *ContainerState) LastActiveAge() string { // FIXME: Return duration (update UI)
 	return time.Since(s.lastActivity).Round(time.Second).String()
 }
 
@@ -68,7 +65,7 @@ func (s *ContainerState) Started() time.Time {
 	return s.started
 }
 
-func (s *containerSettings) StopDelay() string {
+func (s *containerSettings) StopDelay() string { // FIXME: Return duration (update UI)
 	return s.stopDelay.String()
 }
 
@@ -83,35 +80,3 @@ func (s *ContainerState) WaitForPath() string {
 func (s *ContainerState) WaitForMethod() string {
 	return s.waitForMethod
 }
-
-// Wrapper for container results that opaques and adds some methods to that data
-type ContainerWrapper struct {
-	types.Container
-}
-
-func (s *ContainerWrapper) NameID() string {
-	return containerShort(&s.Container)
-}
-
-func (s *ContainerWrapper) ConfigLabels() map[string]string {
-	var matchString = config.Model.LabelPrefix + "."
-
-	ret := make(map[string]string)
-	for k, v := range s.Labels {
-		if strings.HasPrefix(k, matchString) {
-			ret[k[len(matchString):]] = v
-		}
-	}
-	return ret
-}
-
-func wrapContainers(cts ...types.Container) []ContainerWrapper {
-	ret := make([]ContainerWrapper, len(cts))
-	for i, c := range cts {
-		ret[i] = ContainerWrapper{c}
-	}
-	sort.Slice(ret, func(i, j int) bool {
-		return ret[i].NameID() < ret[j].NameID()
-	})
-	return ret
-}

pkg/service/labels.go

@@ -1,53 +0,0 @@
-package service
-
-import (
-	"strconv"
-	"strings"
-	"time"
-	"traefik-lazyload/pkg/config"
-
-	"github.com/docker/docker/api/types"
-	"github.com/sirupsen/logrus"
-)
-
-func labelOrDefault(ct *types.Container, sublabel, dflt string) (string, bool) {
-	if val, ok := ct.Labels[config.SubLabel(sublabel)]; ok {
-		return val, true
-	}
-	return dflt, false
-}
-
-func labelOrDefaultArr(ct *types.Container, sublabel string) ([]string, bool) {
-	if val, ok := ct.Labels[config.SubLabel(sublabel)]; ok {
-		return strings.Split(val, ","), true
-	}
-	return []string{}, false
-}
-
-func labelOrDefaultInt(ct *types.Container, sublabel string, dflt int) (int, bool) {
-	s, ok := labelOrDefault(ct, sublabel, "")
-	if !ok {
-		return dflt, false
-	}
-
-	if val, err := strconv.Atoi(s); err != nil {
-		logrus.Warnf("Unable to parse %s on %s: %v. Using default of %d", sublabel, containerShort(ct), err, dflt)
-		return dflt, false
-	} else {
-		return val, true
-	}
-}
-
-func labelOrDefaultDuration(ct *types.Container, sublabel string, dflt time.Duration) (time.Duration, bool) {
-	s, ok := labelOrDefault(ct, sublabel, "")
-	if !ok {
-		return dflt, false
-	}
-
-	if val, err := time.ParseDuration(s); err != nil {
-		logrus.Warnf("Unable to parse %s on %s: %v. Using default of %s", sublabel, containerShort(ct), err, dflt.String())
-		return dflt, false
-	} else {
-		return val, true
-	}
-}

pkg/service/service.go

@@ -5,14 +5,12 @@ import (
 	"encoding/json"
 	"errors"
 	"sort"
-	"strings"
 	"sync"
 	"time"
-	"traefik-lazyload/pkg/config"
+	"traefik-lazyload/pkg/containers"
 
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/container"
-	"github.com/docker/docker/api/types/filters"
 	"github.com/docker/docker/client"
 	"github.com/sirupsen/logrus"
 )
@@ -21,12 +19,13 @@ type Core struct {
 	mux  sync.Mutex
 	term chan bool
 
-	client *client.Client
+	client    *client.Client
+	discovery *containers.Discovery
 
 	active map[string]*ContainerState // cid -> state
 }
 
-func New(client *client.Client, pollRate time.Duration) (*Core, error) {
+func New(client *client.Client, discovery *containers.Discovery, pollRate time.Duration) (*Core, error) {
 	// Test client and report
 	if info, err := client.Info(context.Background()); err != nil {
 		return nil, err
@@ -36,9 +35,10 @@ func New(client *client.Client, pollRate time.Duration) (*Core, error) {
 
 	// Make core
 	ret := &Core{
-		client: client,
-		active: make(map[string]*ContainerState),
-		term:   make(chan bool),
+		client:    client,
+		discovery: discovery,
+		active:    make(map[string]*ContainerState),
+		term:      make(chan bool),
 	}
 
 	ret.Poll() // initial force-poll to update
@@ -61,7 +61,7 @@ func (s *Core) StartHost(hostname string) (*ContainerState, error) {
 
 	ctx := context.Background()
 
-	ct, err := s.findContainerByHostname(ctx, hostname)
+	ct, err := s.discovery.FindContainerByHostname(ctx, hostname)
 	if err != nil {
 		logrus.Warnf("Unable to find container for host %s: %s", hostname, err)
 		return nil, err
@@ -85,7 +85,7 @@ func (s *Core) StartHost(hostname string) (*ContainerState, error) {
 			ets.lastActivity = time.Now()
 			s.mux.Unlock()
 		}()
-		s.startDependencyFor(ctx, ets.needs, containerShort(ct))
+		s.startDependencyFor(ctx, ets.needs, ct.NameID())
 		s.startContainerSync(ctx, ct)
 	}()
 
@@ -107,26 +107,38 @@ func (s *Core) StopAll() {
 	}
 }
 
-func (s *Core) startContainerSync(ctx context.Context, ct *types.Container) error {
-	if isRunning(ct) {
-		return nil
-	}
-
+// Returns all actively managed containers
+func (s *Core) ActiveContainers() []*ContainerState {
 	s.mux.Lock()
 	defer s.mux.Unlock()
 
+	ret := make([]*ContainerState, 0, len(s.active))
+	for _, item := range s.active {
+		ret = append(ret, item)
+	}
+	sort.Slice(ret, func(i, j int) bool {
+		return ret[i].name < ret[j].name
+	})
+	return ret
+}
+
+func (s *Core) startContainerSync(ctx context.Context, ct *containers.Wrapper) error {
+	if ct.IsRunning() {
+		return nil
+	}
+
 	if err := s.client.ContainerStart(ctx, ct.ID, types.ContainerStartOptions{}); err != nil {
-		logrus.Warnf("Error starting container %s: %s", containerShort(ct), err)
+		logrus.Warnf("Error starting container %s: %s", ct.NameID(), err)
 		return err
 	} else {
-		logrus.Infof("Started container %s", containerShort(ct))
+		logrus.Infof("Started container %s", ct.NameID())
 	}
 	return nil
 }
 
 func (s *Core) startDependencyFor(ctx context.Context, needs []string, forContainer string) {
 	for _, dep := range needs {
-		providers, err := s.findContainersByDepProvider(ctx, dep)
+		providers, err := s.discovery.FindDepProvider(ctx, dep)
 
 		if err != nil {
 			logrus.Errorf("Error finding dependency provider for %s: %v", dep, err)
@@ -134,12 +146,12 @@ func (s *Core) startDependencyFor(ctx context.Context, needs []string, forContai
 			logrus.Warnf("Unable to find any container that provides %s for %s", dep, forContainer)
 		} else {
 			for _, provider := range providers {
-				if !isRunning(&provider) {
-					logrus.Infof("Starting dependency for %s: %s", forContainer, containerShort(&provider))
+				if !provider.IsRunning() {
+					logrus.Infof("Starting dependency for %s: %s", forContainer, provider.NameID())
 
 					s.startContainerSync(ctx, &provider)
 
-					delay, _ := labelOrDefaultDuration(&provider, "provides.delay", 2*time.Second)
+					delay, _ := provider.ConfigDuration("provides.delay", 2*time.Second)
 					logrus.Debugf("Delaying %s to start %s", delay.String(), dep)
 					time.Sleep(delay)
 				}
@@ -167,15 +179,15 @@ func (s *Core) stopDependenciesFor(ctx context.Context, cid string, cts *Contain
 	for dep, needed := range deps {
 		if !needed {
 			logrus.Infof("Stopping dependency %s...", dep)
-			containers, err := s.findContainersByDepProvider(ctx, dep)
+			containers, err := s.discovery.FindDepProvider(ctx, dep)
 			if err != nil {
 				logrus.Errorf("Unable to find dependency provider containers for %s: %v", dep, err)
 			} else if len(containers) == 0 {
 				logrus.Warnf("Unable to find any containers for dependency %s", dep)
 			} else {
 				for _, ct := range containers {
-					if isRunning(&ct) {
-						logrus.Infof("Stopping %s...", containerShort(&ct))
+					if ct.IsRunning() {
+						logrus.Infof("Stopping %s...", ct.NameID())
 						go s.client.ContainerStop(ctx, ct.ID, container.StopOptions{})
 					}
 				}
@@ -215,16 +227,16 @@ func (s *Core) Poll() {
 }
 
 func (s *Core) checkForNewContainersSync(ctx context.Context) {
-	containers, err := s.findAllLazyloadContainers(ctx, false)
+	cts, err := s.discovery.FindAllLazyload(ctx, false)
 	if err != nil {
 		logrus.Warnf("Error checking for new containers: %v", err)
 		return
 	}
 
-	runningContainers := make(map[string]*types.Container)
-	for i, ct := range containers {
-		if isRunning(&ct) {
-			runningContainers[ct.ID] = &containers[i]
+	runningContainers := make(map[string]*containers.Wrapper)
+	for i, ct := range cts {
+		if ct.IsRunning() {
+			runningContainers[ct.ID] = &cts[i]
 		}
 	}
 
@@ -240,7 +252,7 @@ func (s *Core) checkForNewContainersSync(ctx context.Context) {
 	// now, look for containers that are running, but aren't in our active inventory
 	for _, ct := range runningContainers {
 		if _, ok := s.active[ct.ID]; !ok {
-			logrus.Infof("Discovered running container %s", containerShort(ct))
+			logrus.Infof("Discovered running container %s", ct.NameID())
 			s.active[ct.ID] = newStateFromContainer(ct)
 		}
 	}
@@ -306,88 +318,3 @@ func (s *Core) checkContainerForInactivity(ctx context.Context, cid string, ct *
 
 	return false, nil
 }
-
-func (s *Core) findContainersByDepProvider(ctx context.Context, name string) ([]types.Container, error) {
-	filters := filters.NewArgs()
-	filters.Add("label", config.SubLabel("provides")+"="+name)
-	return s.client.ContainerList(ctx, types.ContainerListOptions{
-		Filters: filters,
-		All:     true,
-	})
-}
-
-func (s *Core) findContainerByHostname(ctx context.Context, hostname string) (*types.Container, error) {
-	containers, err := s.findAllLazyloadContainers(ctx, true)
-	if err != nil {
-		return nil, err
-	}
-
-	for _, c := range containers {
-		if hostStr, ok := labelOrDefault(&c, "hosts", ""); ok {
-			hosts := strings.Split(hostStr, ",")
-			if strSliceContains(hosts, hostname) {
-				return &c, nil
-			}
-		} else {
-			// If not defined explicitely, infer from traefik route
-			for k, v := range c.Labels {
-				if strings.Contains(k, "traefik.http.routers.") && strings.Contains(v, hostname) { // TODO: More complex
-					return &c, nil
-				}
-			}
-		}
-	}
-
-	return nil, ErrNotFound
-}
-
-// Finds all containers on node that are labeled with lazyloader config
-func (s *Core) findAllLazyloadContainers(ctx context.Context, includeStopped bool) ([]types.Container, error) {
-	filters := filters.NewArgs()
-	filters.Add("label", config.Model.LabelPrefix)
-
-	return s.client.ContainerList(ctx, types.ContainerListOptions{
-		All:     includeStopped,
-		Filters: filters,
-	})
-}
-
-// Returns all actively managed containers
-func (s *Core) ActiveContainers() []*ContainerState {
-	s.mux.Lock()
-	defer s.mux.Unlock()
-
-	ret := make([]*ContainerState, 0, len(s.active))
-	for _, item := range s.active {
-		ret = append(ret, item)
-	}
-	sort.Slice(ret, func(i, j int) bool {
-		return ret[i].name < ret[j].name
-	})
-	return ret
-}
-
-// Return all containers that qualify to be load-managed (eg. have the tag)
-func (s *Core) QualifyingContainers(ctx context.Context) []ContainerWrapper {
-	ct, err := s.findAllLazyloadContainers(ctx, true)
-	if err != nil {
-		return nil
-	}
-
-	return wrapContainers(ct...)
-}
-
-func (s *Core) ProviderContainers(ctx context.Context) []ContainerWrapper {
-	filters := filters.NewArgs()
-	filters.Add("label", config.SubLabel("provides"))
-
-	ct, err := s.client.ContainerList(ctx, types.ContainerListOptions{
-		Filters: filters,
-		All:     true,
-	})
-	if err != nil {
-		return nil
-	}
-
-	return wrapContainers(ct...)
-}

pkg/service/util.go

@@ -1,9 +1,6 @@
 package service
 
 import (
-	"fmt"
-	"strings"
-
 	"github.com/docker/docker/api/types"
 )
 
@@ -14,38 +11,3 @@ func sumNetworkBytes(networks map[string]types.NetworkStats) (recv int64, send i
 	}
 	return
 }
-
-func shortId(id string) string {
-	const SLEN = 8
-	if len(id) <= SLEN {
-		return id
-	}
-	return id[:SLEN]
-}
-
-func containerShort(c *types.Container) string {
-	var name string
-	if len(c.Names) > 0 {
-		name = trimRootPath(c.Names[0])
-	} else {
-		name = c.Image
-	}
-	return fmt.Sprintf("%s(%s)", name, shortId(c.ID))
-}
-
-func trimRootPath(s string) string {
-	return strings.TrimPrefix(s, "/")
-}
-
-func isRunning(c *types.Container) bool {
-	return c.State == "running"
-}
-
-func strSliceContains(slice []string, s string) bool {
-	for _, item := range slice {
-		if item == s {
-			return true
-		}
-	}
-	return false
-}