Implement the config sync with the backend

consumer.go

@@ -99,7 +99,9 @@ func (c *consumer) connect() (deliveries <-chan amqp.Delivery, err error) {
 
 	// all the bindings from our queue to the topic exchange
 	for _, exchange := range c.exchanges {
-		log.Printf("[Conn] Binding to exchange %s with routing keys %v", exchange.name, exchange.bindingKeys)
+		if *brokerDebugging {
+			log.Printf("[Conn] Binding to exchange %s with routing keys %v", exchange.name, exchange.bindingKeys)
+		}
 		for _, bindingKey := range exchange.bindingKeys {
 			if err = c.channel.QueueBind(
 				c.queue.Name,  // queue name

main.go

 package main
 
 import (
+	"bytes"
 	"encoding/json"
+	"fmt"
 	"io/ioutil"
 	"log"
 	"net/http"
@@ -19,7 +21,6 @@ type (
 
 	fetchedConfig struct {
 		RabbitMQConfig rabbitMQConfig `json:"rabbitmq_config"`
-		Services       []service      `json:"services"`
 		Site           string         `json:"site"`
 	}
 
@@ -45,6 +46,12 @@ type (
 		RabbitMQConfig         rabbitMQConfig
 		Site                   string
 	}
+
+	// strippedConfig is sent to the backend on startup
+	strippedConfig struct {
+		Services        []service              `json:"services"`
+		GroupToServices map[string]([]service) `json:"group_to_services"`
+	}
 )
 
 var (
@@ -60,6 +67,7 @@ var (
 	configFile       = app.Arg("config", "Config file to file to use.").Required().String()
 	scriptDebugging  = app.Flag("debug-scripts", "Display debugging info concerning executed scripts").Bool()
 	backendDebugging = app.Flag("debug-backend", "Display debugging info concerning the backend").Bool()
+	brokerDebugging  = app.Flag("debug-broker", "Display debugging info concerning the message broker").Bool()
 )
 
 func logError(err error, msg string) {
@@ -68,13 +76,28 @@ func logError(err error, msg string) {
 	}
 }
 
-func (c *config) fetchConfig() (err error) {
-	req, err := http.NewRequest("GET", "https://"+c.Host+"/backend/clientapi/config", nil)
+func (c *config) syncConfig() (err error) {
+	// we inform the backend which services we provide
+	strippedConfigBytes, err := json.Marshal(strippedConfig{
+		Services:        c.Services,
+		GroupToServices: c.GroupToServices,
+	})
+	if err != nil {
+		return
+	}
+
+	// update the services tracked by the backend
+	req, err := http.NewRequest(
+		"PUT",
+		"https://"+c.Host+"/backend/clientapi/config",
+		bytes.NewReader(strippedConfigBytes),
+	)
 	if err != nil {
 		return
 	}
 
 	req.SetBasicAuth(c.Username, c.Password)
+	req.Header.Set("Content-Type", "application/json")
 	resp, err := client.Do(req)
 	if err != nil {
 		return
@@ -85,6 +108,12 @@ func (c *config) fetchConfig() (err error) {
 	if err != nil {
 		return
 	}
+
+	if resp.StatusCode != 200 {
+		err = fmt.Errorf("Unable to sync configuration (backend returned %v)", resp.Status)
+		return
+	}
+
 	var fetchedConfig fetchedConfig
 	err = json.Unmarshal(body, &fetchedConfig)
 	if err != nil {
@@ -95,18 +124,20 @@ func (c *config) fetchConfig() (err error) {
 	c.RabbitMQConfig = fetchedConfig.RabbitMQConfig
 	c.Site = fetchedConfig.Site
 
-	permittedServices := fetchedConfig.Services
-	log.Printf("[Conf] Permitted services: %s", permittedServices)
+	// we *disabled* service filtering as clients can push the services to the backend
+	/*
+		permittedServices := fetchedConfig.Services
+		log.Printf("[Conf] Permitted services: %s", permittedServices)
+			if len(c.Services) == 0 {
+				log.Printf("[Conf] Config specifies no services. Using all permitted services")
+			} else {
+				// if the config specifies services we check if they are all permitted
+				c.Services = filterPermitted(permittedServices, c.Services)
 
-	if len(c.Services) == 0 {
-		log.Printf("[Conf] Config specifies no services. Using all permitted services")
-	} else {
-		// if the config specifies services we check if they are all permitted
-		c.Services = filterPermitted(permittedServices, c.Services)
-	}
-	log.Printf("[Conf] Services: %s", c.Services)
+			}
+	*/
 
-	log.Printf("[Conf] Groups: %s", c.GroupToServices)
+	log.Printf("[Conf] Synchronised with backend")
 
 	return
 }
@@ -169,12 +200,15 @@ func getConfig(configFile string) (c config, err error) {
 	}
 
 	// fetch the remote configuration
-	err = c.fetchConfig()
+	err = c.syncConfig()
 	if err != nil {
 		log.Fatalf("[Conf] Error fetching remote config: %s", err)
 		return
 	}
 
+	log.Printf("[Conf] Services: %s", c.Services)
+	log.Printf("[Conf] Groups: %s", c.GroupToServices)
+
 	// initialize the task queues
 	c.NewTasks = make(chan task)
 	c.DoneTasks = make(chan taskExecution)