Add logging, update haproxy example

container_monitor.go

 
 import (
 	"context"
-	"fmt"
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/filters"
 	"github.com/docker/docker/client"
+	"go.uber.org/zap"
 	"time"
 )
 
 type ContainerMonitor struct {
+	logger             *zap.SugaredLogger
 	newContainers      chan<- Container
 	goneContainerNames chan<- string
 	client             *client.Client
 	expiryTimer        *time.Timer
 }
 
-func NewContainerMonitor(client *client.Client, newContainerChannel chan<- Container, goneContainerChannel chan<- string) *ContainerMonitor {
+func NewContainerMonitor(logger *zap.SugaredLogger, client *client.Client, newContainerChannel chan<- Container, goneContainerChannel chan<- string) *ContainerMonitor {
 	timer := time.NewTimer(time.Hour)
 	timer.Stop()
 
 	return &ContainerMonitor{
+		logger:             logger,
 		newContainers:      newContainerChannel,
 		goneContainerNames: goneContainerChannel,
 		client:             client,
 			c.publishExpiredContainers()
 
 		case err := <-errChan:
-			panic(err)
+			c.logger.Fatal("Error received from docker events API", err)
 		}
 	}
 }
 func (c *ContainerMonitor) publishExistingContainers() {
 	containers, err := c.client.ContainerList(context.Background(), types.ContainerListOptions{})
 	if err != nil {
-		panic(err)
+		c.logger.Fatal("Error received trying to list containers", err)
 	}
 
 	for _, container := range containers {
+		c.logger.Infof("Found existing container %s", container.Names[0][1:])
 		c.newContainers <- Container{
 			Id:     container.ID,
 			Name:   container.Names[0][1:],
 func (c *ContainerMonitor) publishNewContainer(id string) {
 	container, err := c.client.ContainerInspect(context.Background(), id)
 	if err != nil {
-		panic(err)
+		c.logger.Fatal("Error received trying to inspect container", err)
 	}
 	c.newContainers <- Container{
 		Id:     container.ID,
 		Name:   container.Name[1:],
 		Labels: container.Config.Labels,
 	}
+	c.logger.Info("Found new container %s", container.Name[1:])
 	delete(c.expiryTimes, container.Name[1:])
 }
 
 	now := time.Now()
 	expiryTime := now.Add(c.deletionTime)
 	c.expiryTimes[name] = expiryTime
-	fmt.Printf("Scheduling expiry timer for %s\n", name)
+	c.logger.Info("Scheduling expiry timer for %s", name)
 	if c.nextExpiry.Before(now) || c.nextExpiry.After(expiryTime) {
-		fmt.Printf("Starting expiry timer with default duration\n")
+		c.logger.Debug("Starting expiry timer with default duration")
 		c.expiryTimer.Reset(c.deletionTime + 1*time.Second)
 		c.nextExpiry = expiryTime
 	}
 
 	for name, expiryTime := range c.expiryTimes {
 		if expiryTime.Before(now) {
-			fmt.Printf("Expiring %s\n", name)
+			c.logger.Info("Expiring %s", name)
 			delete(c.expiryTimes, name)
 			c.goneContainerNames <- name
 		} else if next == 0 || expiryTime.Sub(now) < next {
 	}
 
 	if next > 0 {
-		fmt.Printf("Starting expiry timer with duration %s\n", next)
+		c.logger.Debugf("Starting expiry timer with duration %s\n", next)
 		c.expiryTimer.Reset(next + 1*time.Second)
 		c.nextExpiry = now.Add(next)
 	}

dotege.go

 import (
 	"fmt"
 	"github.com/docker/docker/client"
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
 	"os"
 	"os/signal"
 	"strings"
 	Containers   []Container
 }
 
+type Config struct {
+	Templates []TemplateConfig
+	Labels    LabelConfig
+}
+
 func monitorSignals() <-chan bool {
 	signals := make(chan os.Signal, 1)
 	done := make(chan bool, 1)
 }
 
 func main() {
+	config := zap.NewDevelopmentConfig()
+	config.DisableCaller = true
+	config.EncoderConfig.EncodeLevel = zapcore.CapitalColorLevelEncoder
+	config.OutputPaths = []string{"stdout"}
+	config.ErrorOutputPaths = []string{"stdout"}
+	logger, _ := config.Build()
+	sugar := logger.Sugar()
+	sugar.Info("Dotege is starting")
+
 	done := monitorSignals()
 	containerChan := make(chan Container, 1)
 	expiryChan := make(chan string, 1)
 		panic(err)
 	}
 
-	templateGenerator := NewTemplateGenerator()
+	templateGenerator := NewTemplateGenerator(sugar)
 	templateGenerator.AddTemplate(TemplateConfig{
 		Source:      "./templates/domains.txt.tpl",
 		Destination: "domains.txt",
 	})
+	templateGenerator.AddTemplate(TemplateConfig{
+		Source:      "./templates/haproxy.cfg.tpl",
+		Destination: "haproxy.cfg",
+	})
 
-	monitor := NewContainerMonitor(cli, containerChan, expiryChan)
+	monitor := NewContainerMonitor(sugar, cli, containerChan, expiryChan)
 	go monitor.Monitor()
 
 	go func() {

go.mod

 module github.com/csmith/dotege
 
 require (
+	github.com/Microsoft/go-winio v0.4.11 // indirect
 	github.com/docker/distribution v2.7.1+incompatible // indirect
 	github.com/docker/docker v1.13.1
 	github.com/docker/go-connections v0.4.0 // indirect
 	github.com/docker/go-units v0.3.3 // indirect
-	github.com/gorilla/mux v1.7.0 // indirect
 	github.com/opencontainers/go-digest v1.0.0-rc1 // indirect
 	github.com/pkg/errors v0.8.1 // indirect
-	github.com/sirupsen/logrus v1.3.0 // indirect
-	golang.org/x/net v0.0.0-20190206173232-65e2d4e15006 // indirect
+	github.com/stretchr/testify v1.3.0 // indirect
+	go.uber.org/atomic v1.3.2 // indirect
+	go.uber.org/multierr v1.1.0 // indirect
+	go.uber.org/zap v1.9.1
+	golang.org/x/net v0.0.0-20190213061140-3a22650c66bd // indirect
+	golang.org/x/sys v0.0.0-20190213121743-983097b1a8a3 // indirect
 )

go.sum

-github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/Microsoft/go-winio v0.4.11 h1:zoIOcVf0xPN1tnMVbTtEdI+P8OofVk3NObnwOQ6nK2Q=
+github.com/Microsoft/go-winio v0.4.11/go.mod h1:VhR8bwka0BXejwEJY73c50VrPtXAaKcyvVC4A4RozmA=
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/docker/distribution v2.7.1+incompatible h1:a5mlkVzth6W5A4fOsS3D2EO5BUmsJpcB+cRlLU7cSug=
 github.com/docker/distribution v2.7.1+incompatible/go.mod h1:J2gT2udsDAN96Uj4KfcMRqY0/ypR+oyYUYmja8H+y+w=
 github.com/docker/docker v1.13.1 h1:IkZjBSIc8hBjLpqeAbeE5mca5mNgeatLHBy3GO78BWo=
 github.com/docker/go-connections v0.4.0/go.mod h1:Gbd7IOopHjR8Iph03tsViu4nIes5XhDvyHbTtUxmeec=
 github.com/docker/go-units v0.3.3 h1:Xk8S3Xj5sLGlG5g67hJmYMmUgXv5N4PhkjJHHqrwnTk=
 github.com/docker/go-units v0.3.3/go.mod h1:fgPhTUdO+D/Jk86RDLlptpiXQzgHJF7gydDDbaIK4Dk=
-github.com/gorilla/mux v1.7.0 h1:tOSd0UKHQd6urX6ApfOn4XdBMY6Sh1MfxV3kmaazO+U=
-github.com/gorilla/mux v1.7.0/go.mod h1:1lud6UwP+6orDFRuTfBEV8e9/aOM/c4fVVCaMa2zaAs=
-github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
 github.com/opencontainers/go-digest v1.0.0-rc1 h1:WzifXhOVOEOuFYOJAW6aQqW0TooG2iki3E3Ii+WN7gQ=
 github.com/opencontainers/go-digest v1.0.0-rc1/go.mod h1:cMLVZDEM3+U2I4VmLI6N8jQYUd2OVphdqWwCJHrFt2s=
 github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/sirupsen/logrus v1.3.0 h1:hI/7Q+DtNZ2kINb6qt/lS+IyXnHQe9e90POfeewL/ME=
-github.com/sirupsen/logrus v1.3.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=
-github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
-golang.org/x/crypto v0.0.0-20180904163835-0709b304e793 h1:u+LnwYTOOW7Ukr/fppxEb1Nwz0AtPflrblfvUudpo+I=
-golang.org/x/crypto v0.0.0-20180904163835-0709b304e793/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
-golang.org/x/net v0.0.0-20190206173232-65e2d4e15006 h1:bfLnR+k0tq5Lqt6dflRLcZiz6UaXCMt3vhYJ1l4FQ80=
-golang.org/x/net v0.0.0-20190206173232-65e2d4e15006/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
-golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33 h1:I6FyU15t786LL7oL/hn43zqTuEGr4PN7F4XJ1p4E3Y8=
-golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
+github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+go.uber.org/atomic v1.3.2 h1:2Oa65PReHzfn29GpvgsYwloV9AVFHPDk8tYxt2c2tr4=
+go.uber.org/atomic v1.3.2/go.mod h1:gD2HeocX3+yG+ygLZcrzQJaqmWj9AIm7n08wl/qW/PE=
+go.uber.org/multierr v1.1.0 h1:HoEmRHQPVSqub6w2z2d2EOVs2fjyFRGyofhKuyDq0QI=
+go.uber.org/multierr v1.1.0/go.mod h1:wR5kodmAFQ0UK8QlbwjlSNy0Z68gJhDJUG5sjR94q/0=
+go.uber.org/zap v1.9.1 h1:XCJQEf3W6eZaVwhRBof6ImoYGJSITeKWsyeh3HFu/5o=
+go.uber.org/zap v1.9.1/go.mod h1:vwi/ZaCAaUcBkycHslxD9B2zi4UTXhF60s6SWpuDF0Q=
+golang.org/x/net v0.0.0-20190213061140-3a22650c66bd h1:HuTn7WObtcDo9uEEU7rEqL0jYthdXAmZ6PP+meazmaU=
+golang.org/x/net v0.0.0-20190213061140-3a22650c66bd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/sys v0.0.0-20190213121743-983097b1a8a3 h1:+KlxhGbYkFs8lMfwKn+2ojry1ID5eBSMXprS2u/wqCE=
+golang.org/x/sys v0.0.0-20190213121743-983097b1a8a3/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=

template_generator.go

 package main
 
 import (
-	"fmt"
+	"go.uber.org/zap"
 	"io/ioutil"
 	"path"
 	"sort"
 }
 
 type TemplateGenerator struct {
+	logger *zap.SugaredLogger
 	templates []*Template
 }
 
 	},
 }
 
-func NewTemplateGenerator() *TemplateGenerator {
-	return &TemplateGenerator{}
+func NewTemplateGenerator(logger *zap.SugaredLogger) *TemplateGenerator {
+	return &TemplateGenerator{
+		logger: logger,
+	}
 }
 
 func (t *TemplateGenerator) AddTemplate(config TemplateConfig) {
+	t.logger.Infof("Adding template from %s, writing to %s", config.Source, config.Destination)
 	tmpl, err := template.New(path.Base(config.Source)).Funcs(funcMap).ParseFiles(config.Source)
 	if err != nil {
-		panic(err)
+		t.logger.Fatal("Unable to parse template", err)
 	}
 
 	buf, _ := ioutil.ReadFile(config.Destination)
 
 func (t *TemplateGenerator) Generate(context Context) {
 	for _, tmpl := range t.templates {
-		fmt.Printf("Checking %s\n", tmpl.config.Source)
+		t.logger.Debugf("Checking for updates to %s", tmpl.config.Source)
 		builder := &strings.Builder{}
 		err := tmpl.template.Execute(builder, context)
 		if err != nil {
 			panic(err)
 		}
 		if tmpl.content != builder.String() {
-			fmt.Printf("--- %s updated, writing to %s ---\n", tmpl.config.Source, tmpl.config.Destination)
-			fmt.Printf("%s", builder.String())
-			fmt.Printf("--- / writing %s ---\n", tmpl.config.Destination)
+			t.logger.Debugf("%s has been updated, writing to %s", tmpl.config.Source, tmpl.config.Destination)
+			t.logger.Debug(builder.String())
 			tmpl.content = builder.String()
 			err = ioutil.WriteFile(tmpl.config.Destination, []byte(builder.String()), 0666)
 			if err != nil {
-				panic(err)
+				t.logger.Fatal("Unable to write template", err)
 			}
 		}
 	}

templates/haproxy.cfg.tpl

     bind    :80
     redirect scheme https code 301 if !{ ssl_fc }
     http-response set-header Strict-Transport-Security max-age=15768000
-{{ range .Containers }}
-    {{- if index .Labels "com.chameth.proxy" -}}
-        {{- if index .Labels "com.chameth.vhost" }}
-    use_backend {{ .Name }} if { hdr(host) -i {{ index .Labels "com.chameth.vhost" | split "," | join " || hdr(host) -i " }} }
-        {{- end -}}
-    {{- end -}}
-{{ end }}
-{{ range .Containers }}
-    {{- if index .Labels "com.chameth.proxy" }}
-backend {{ .Name }}
+{{- range .Hostnames }}
+    use_backend {{ .Name | replace "." "_" }} if {hdr(host) -i {{ .Name }}
+        {{- range $san, $_ := .Alternatives }} || hdr(host) -i {{ $san }} {{- end -}}
+    }
+{{- end }}
+{{- range .Hostnames }}
+
+backend {{ .Name | replace "." "_" }}
     mode http
+    {{- range .Containers }}
+        {{- if index .Labels "com.chameth.proxy" }}
     server server1 {{ .Name }}:{{ index .Labels "com.chameth.proxy" }} check resolvers docker_resolver
+        {{- end -}}
     {{- end -}}
 {{ end }}