feat: Multiple brokers (#125)

* multiple brokers

* disable cgo for build target

* linting

Makefile

@@ -13,8 +13,8 @@ clean:
 	rm -rf ./$(BUILD_DIR)
 
 build: version-info
-	go build -ldflags="-X '$(MODULE)/internal.BuildVersion=${VERSION}' -X '$(MODULE)/internal.CommitHash=${COMMIT_HASH}'" -o $(BINARY_NAME_SERVER) cmd/server/server.go
-	go build -ldflags="-X '$(MODULE)/internal.BuildVersion=${VERSION}' -X '$(MODULE)/internal.CommitHash=${COMMIT_HASH}'" -o $(BINARY_NAME_CLIENT) cmd/client/client.go
+	CGO_ENABLED=0 go build -ldflags="-X '$(MODULE)/internal.BuildVersion=${VERSION}' -X '$(MODULE)/internal.CommitHash=${COMMIT_HASH}'" -o $(BINARY_NAME_SERVER) cmd/server/server.go
+	CGO_ENABLED=0 go build -ldflags="-X '$(MODULE)/internal.BuildVersion=${VERSION}' -X '$(MODULE)/internal.CommitHash=${COMMIT_HASH}'" -o $(BINARY_NAME_CLIENT) cmd/client/client.go
 
 release: clean version-info cross-build-client cross-build-server
 	sha256sum $(BUILD_DIR)/dyndns-* > $(CHECKSUM_FILE)

client/client.go

@@ -1,14 +1,14 @@
 package client
 
 import (
+	"errors"
+	"fmt"
+	"github.com/rs/zerolog/log"
 	"github.com/soerenschneider/dyndns/client/resolvers"
 	"github.com/soerenschneider/dyndns/internal/common"
 	"github.com/soerenschneider/dyndns/internal/events"
 	"github.com/soerenschneider/dyndns/internal/metrics"
 	"github.com/soerenschneider/dyndns/internal/verification"
-	"errors"
-	"fmt"
-	"github.com/rs/zerolog/log"
 	"time"
 )
 
@@ -28,25 +28,25 @@ type State interface {
 type Client struct {
 	signature       verification.SignatureKeypair
 	resolver        resolvers.IpResolver
-	dispatcher      events.EventDispatch
+	dispatchers     []events.EventDispatch
 	state           State
 	lastStateChange time.Time
 }
 
-func NewClient(resolver resolvers.IpResolver, signature verification.SignatureKeypair, dispatcher events.EventDispatch) (*Client, error) {
+func NewClient(resolver resolvers.IpResolver, signature verification.SignatureKeypair, dispatchers []events.EventDispatch) (*Client, error) {
 	if resolver == nil {
 		return nil, errors.New("no resolver provided")
 	}
 	if signature == nil {
 		return nil, errors.New("no signature provider given")
 	}
-	if dispatcher == nil {
-		return nil, errors.New("no dispatcher provided")
+	if dispatchers == nil || len(dispatchers) == 0 {
+		return nil, errors.New("no dispatchers provided")
 	}
 
 	c := Client{
 		resolver:        resolver,
-		dispatcher:      dispatcher,
+		dispatchers:     dispatchers,
 		signature:       signature,
 		state:           &initialState{},
 		lastStateChange: time.Now(),
@@ -106,10 +106,12 @@ func (client *Client) Resolve(prev *common.ResolvedIp) (*common.ResolvedIp, erro
 			Signature: signature,
 		}
 
-		err := client.dispatcher.Notify(env)
-		if err != nil {
-			metrics.UpdateDispatchErrors.WithLabelValues(client.resolver.Host()).Inc()
-			return resolvedIp, fmt.Errorf("could not dispatch ip update notification: %v", err)
+		for _, dispatcher := range client.dispatchers {
+			err := dispatcher.Notify(env)
+			if err != nil {
+				metrics.UpdateDispatchErrors.WithLabelValues(client.resolver.Host()).Inc()
+				return resolvedIp, fmt.Errorf("could not dispatch ip update notification: %v", err)
+			}
 		}
 		metrics.UpdatesDispatched.Inc()
 	}

client/resolvers/http_resolver.go

@@ -1,10 +1,10 @@
 package resolvers
 
 import (
-	"github.com/soerenschneider/dyndns/internal/common"
 	"fmt"
 	"github.com/hashicorp/go-retryablehttp"
 	"github.com/rs/zerolog/log"
+	"github.com/soerenschneider/dyndns/internal/common"
 	"io/ioutil"
 	"math/rand"
 	"net"

client/resolvers/interface_resolver.go

@@ -1,9 +1,9 @@
 package resolvers
 
 import (
-	"github.com/soerenschneider/dyndns/internal/common"
 	"errors"
 	"fmt"
+	"github.com/soerenschneider/dyndns/internal/common"
 	"net"
 	"time"
 )

client/states.go

@@ -1,10 +1,10 @@
 package client
 
 import (
-	"github.com/soerenschneider/dyndns/internal/common"
-	"github.com/soerenschneider/dyndns/internal/util"
 	"fmt"
 	"github.com/rs/zerolog/log"
+	"github.com/soerenschneider/dyndns/internal/common"
+	"github.com/soerenschneider/dyndns/internal/util"
 	"math/rand"
 	"time"
 )

cmd/client/client.go

@@ -94,13 +94,16 @@ func RunClient(conf *conf.ClientConf) {
 		resolver, _ = resolvers.NewHttpResolver(conf.Host)
 	}
 
-	var dispatcher events.EventDispatch
-	dispatcher, err = mqtt.NewMqttDispatch(conf.Broker, conf.Host, fmt.Sprintf("dyndns/%s", conf.Host))
-	if err != nil {
-		log.Fatal().Msgf("Could not build mqtt dispatcher: %v", err)
+	var dispatchers []events.EventDispatch
+	for _, broker := range conf.Brokers {
+		dispatcher, err := mqtt.NewMqttDispatch(broker, conf.Host, fmt.Sprintf("dyndns/%s", conf.Host))
+		if err != nil {
+			log.Fatal().Msgf("Could not build mqtt dispatcher: %v", err)
+		}
+		dispatchers = append(dispatchers, dispatcher)
 	}
 
-	client, err := client.NewClient(resolver, keypair, dispatcher)
+	client, err := client.NewClient(resolver, keypair, dispatchers)
 	if err != nil {
 		log.Fatal().Msgf("could not build client: %v", err)
 	}

cmd/server/server.go

@@ -1,6 +1,12 @@
 package main
 
 import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"github.com/aws/aws-sdk-go/aws/credentials"
+	paho "github.com/eclipse/paho.mqtt.golang"
+	"github.com/rs/zerolog/log"
 	"github.com/soerenschneider/dyndns/conf"
 	"github.com/soerenschneider/dyndns/internal"
 	"github.com/soerenschneider/dyndns/internal/common"
@@ -10,12 +16,6 @@ import (
 	"github.com/soerenschneider/dyndns/server"
 	"github.com/soerenschneider/dyndns/server/dns"
 	"github.com/soerenschneider/dyndns/server/vault"
-	"encoding/json"
-	"flag"
-	"fmt"
-	"github.com/aws/aws-sdk-go/aws/credentials"
-	paho "github.com/eclipse/paho.mqtt.golang"
-	"github.com/rs/zerolog/log"
 	"os"
 	"os/signal"
 	"syscall"
@@ -94,7 +94,7 @@ func RunServer(configPath string) {
 	}
 	conf.Print()
 
-	mqttServer, err := mqtt.NewMqttServer(conf.Broker, conf.ClientId, notificationTopic, HandleChangeRequest)
+	mqttServer, err := mqtt.NewMqttServer(conf.Brokers, conf.ClientId, notificationTopic, HandleChangeRequest)
 	if err != nil {
 		log.Fatal().Msgf("Could not build mqtt dispatcher: %v", err)
 	}

conf/client.go

@@ -1,11 +1,11 @@
 package conf
 
 import (
-	"github.com/soerenschneider/dyndns/internal/metrics"
 	"encoding/json"
 	"errors"
 	"fmt"
 	"github.com/rs/zerolog/log"
+	"github.com/soerenschneider/dyndns/internal/metrics"
 	"io/ioutil"
 )
 

conf/mqtt.go

@@ -6,18 +6,20 @@ import (
 )
 
 type MqttConfig struct {
-	Broker   string `json:"broker"`
-	ClientId string `json:"client_id"`
+	Brokers  []string `json:"brokers"`
+	ClientId string   `json:"client_id"`
 }
 
 func (conf *MqttConfig) Print() {
-	log.Info().Msgf("Broker=%s", conf.Broker)
+	log.Info().Msgf("Brokers=%v", conf.Brokers)
 	log.Info().Msgf("ClientId=%s", conf.ClientId)
 }
 
 func (conf *MqttConfig) Validate() error {
-	if !IsValidUrl(conf.Broker) {
-		return fmt.Errorf("no valid host given: %s", conf.Broker)
+	for _, broker := range conf.Brokers {
+		if !IsValidUrl(broker) {
+			return fmt.Errorf("no valid host given: %s", broker)
+		}
 	}
 
 	return nil

conf/server.go

@@ -1,12 +1,12 @@
 package conf
 
 import (
-	"github.com/soerenschneider/dyndns/internal/metrics"
-	"github.com/soerenschneider/dyndns/internal/verification"
 	"encoding/json"
 	"errors"
 	"fmt"
 	"github.com/rs/zerolog/log"
+	"github.com/soerenschneider/dyndns/internal/metrics"
+	"github.com/soerenschneider/dyndns/internal/verification"
 	"io/ioutil"
 )
 

internal/events/eventbus.go

@@ -1,8 +1,8 @@
 package events
 
 import (
-	"github.com/soerenschneider/dyndns/internal/common"
 	mqtt "github.com/eclipse/paho.mqtt.golang"
+	"github.com/soerenschneider/dyndns/internal/common"
 )
 
 type EventDispatch interface {

internal/events/mqtt/mqtt_dispatcher.go

@@ -1,13 +1,13 @@
 package mqtt
 
 import (
-	"github.com/soerenschneider/dyndns/internal/common"
-	"github.com/soerenschneider/dyndns/internal/metrics"
 	"encoding/json"
 	"errors"
 	"fmt"
 	mqtt "github.com/eclipse/paho.mqtt.golang"
 	"github.com/rs/zerolog/log"
+	"github.com/soerenschneider/dyndns/internal/common"
+	"github.com/soerenschneider/dyndns/internal/metrics"
 	"time"
 )
 
@@ -27,7 +27,7 @@ var connectLostHandler mqtt.ConnectionLostHandler = func(client mqtt.Client, err
 	metrics.MqttConnectionsLostTotal.Inc()
 }
 
-func NewMqttDispatch(broker, clientId, notificationTopic string) (*MqttBus, error) {
+func NewMqttDispatch(broker string, clientId, notificationTopic string) (*MqttBus, error) {
 	opts := mqtt.NewClientOptions()
 	opts.AddBroker(broker)
 	opts.SetClientID(clientId)
@@ -47,9 +47,11 @@ func NewMqttDispatch(broker, clientId, notificationTopic string) (*MqttBus, erro
 	}, nil
 }
 
-func NewMqttServer(broker, clientId, notificationTopic string, handler func(client mqtt.Client, msg mqtt.Message)) (*MqttBus, error) {
+func NewMqttServer(brokers []string, clientId, notificationTopic string, handler func(client mqtt.Client, msg mqtt.Message)) (*MqttBus, error) {
 	opts := mqtt.NewClientOptions()
-	opts.AddBroker(broker)
+	for _, broker := range brokers {
+		opts.AddBroker(broker)
+	}
 	opts.SetClientID(clientId)
 	opts.OnConnect = connectHandler
 	opts.OnConnectionLost = connectLostHandler

internal/util/logging.go

@@ -1,9 +1,9 @@
 package util
 
 import (
-	"github.com/soerenschneider/dyndns/internal"
 	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/log"
+	"github.com/soerenschneider/dyndns/internal"
 	"golang.org/x/crypto/ssh/terminal"
 	"os"
 	"time"

internal/verification/common.go

@@ -1,8 +1,8 @@
 package verification
 
 import (
-	"github.com/soerenschneider/dyndns/internal/common"
 	"encoding/base64"
+	"github.com/soerenschneider/dyndns/internal/common"
 )
 
 func DecodeBase64(input string) ([]byte, error) {

internal/verification/ed25519.go

@@ -3,11 +3,11 @@ package verification
 import (
 	"crypto/ed25519"
 	"crypto/rand"
-	"github.com/soerenschneider/dyndns/internal/common"
 	"encoding/base64"
 	"encoding/json"
 	"fmt"
 	"github.com/rs/zerolog/log"
+	"github.com/soerenschneider/dyndns/internal/common"
 	"io/ioutil"
 )
 

server/dns/route53.go

@@ -1,14 +1,14 @@
 package dns
 
 import (
-	"github.com/soerenschneider/dyndns/internal/common"
 	"errors"
 	"fmt"
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/aws/credentials"
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/route53"
 	"github.com/rs/zerolog/log"
+	"github.com/soerenschneider/dyndns/internal/common"
 )
 
 type Route53Propagator struct {

server/server.go

@@ -1,16 +1,16 @@
 package server
 
 import (
+	"errors"
+	"fmt"
+	"github.com/rs/zerolog/log"
 	"github.com/soerenschneider/dyndns/conf"
 	"github.com/soerenschneider/dyndns/internal/common"
 	"github.com/soerenschneider/dyndns/internal/events"
 	"github.com/soerenschneider/dyndns/internal/metrics"
 	"github.com/soerenschneider/dyndns/internal/util"
 	"github.com/soerenschneider/dyndns/internal/verification"
 	"github.com/soerenschneider/dyndns/server/dns"
-	"errors"
-	"fmt"
-	"github.com/rs/zerolog/log"
 	"time"
 )
 

server/vault/client.go

@@ -2,14 +2,14 @@ package vault
 
 import (
 	"bytes"
-	"github.com/soerenschneider/dyndns/conf"
-	"github.com/soerenschneider/dyndns/internal/metrics"
 	"encoding/json"
 	"errors"
 	"fmt"
 	"github.com/aws/aws-sdk-go/aws/credentials"
 	"github.com/hashicorp/go-retryablehttp"
 	"github.com/rs/zerolog/log"
+	"github.com/soerenschneider/dyndns/conf"
+	"github.com/soerenschneider/dyndns/internal/metrics"
 	"io/ioutil"
 	"net/http"
 	"time"

server/vault/client_test.go

@@ -1,8 +1,8 @@
 package vault
 
 import (
-	"github.com/soerenschneider/dyndns/conf"
 	"github.com/aws/aws-sdk-go/aws/credentials"
+	"github.com/soerenschneider/dyndns/conf"
 	"net/http"
 	"reflect"
 	"testing"