Implement custom endpoint for modules

Every module now has a "endpoint" setting in its configuration file.
Also implemented some simple configuration validation for an easier
migration.

cpthook.yml.example

@@ -20,12 +20,15 @@ irc:
         password: "VerySecure!"
 
 modules:
-    prometheus:
-        enabled: true
+    my-prom-endpoint:
+        endpoint: "/prom"
+        type: "prometheus"
         channel: "#prometheusChannel"
         hostname_filter: "(\\w*)\\.company.com:\\d{4}"
+
     gitlab:
-        enabled: true
+        endpoint: "/gitlab"
+        type: "gitlab"
         default: "#defaultChannel"
         commit_limit: 3
         groups:
@@ -35,15 +38,22 @@ modules:
             "myGitlabGroup/mySpecialGitlabProject":
                 - "#specificChannel"
     simple:
-        enabled: True
+        endpoint: "/simple"
+        type: "simple"
         default_channel: "#defaultChannel"
-    icinga2:
-      enabled: True
-      default: "#monitoring"
-      hostgroups:
-          "webservers":
-              - "#monitoring-web"
-      explicit:
-          "host.example.tld":
-              - "#monitoring-example"
 
+    another-simple:
+        endpoint: "/simple2"
+        type: "simple"
+        default_channel: "#defaultChannel"
+
+    icinga2:
+        endpoint: "/betterthannagios"
+        type: "icinga"
+        default: "#monitoring"
+        hostgroups:
+            "webservers":
+                - "#monitoring-web"
+        explicit:
+            "host.example.tld":
+                - "#monitoring-example"

input/gitlab.go

@@ -98,10 +98,6 @@ func (m GitlabModule) GetChannelList() []string {
 	return all
 }
 
-func (m GitlabModule) GetEndpoint() string {
-	return "/gitlab"
-}
-
 func (m GitlabModule) GetHandler() http.HandlerFunc {
 
 	const pushCompareString = "[\x0312{{ .Project.Name }}\x03] {{ .UserName }} pushed {{ .TotalCommits }} commits to \x0305{{ .Branch }}\x03 {{ .Project.WebURL }}/compare/{{ .BeforeCommit }}...{{ .AfterCommit }}"

input/helper.go

@@ -10,7 +10,6 @@ import (
 type Module interface {
 	Init(c *viper.Viper, channel *chan IRCMessage)
 	GetChannelList() []string
-	GetEndpoint() string
 	GetHandler() http.HandlerFunc
 }
 

input/icinga2.go

@@ -3,13 +3,14 @@ package input
 import (
 	"bytes"
 	"encoding/json"
-	"github.com/dustin/go-humanize"
-	log "github.com/sirupsen/logrus"
 	"net/http"
 	"strings"
 	"text/template"
 	"time"
 
+	"github.com/dustin/go-humanize"
+	log "github.com/sirupsen/logrus"
+
 	"github.com/spf13/viper"
 )
 
@@ -201,10 +202,6 @@ func (m Icinga2Module) GetChannelList() []string {
 	return all
 }
 
-func (m Icinga2Module) GetEndpoint() string {
-	return "/icinga2"
-}
-
 func (m Icinga2Module) GetHandler() http.HandlerFunc {
 
 	const serviceStateChangeString = "Service \x0312{{ .Service.DisplayName }}\x03 (\x0314{{ .Host.DisplayName }}\x03) transitioned from state {{ .Service.ColoredLastState }} to {{ .Service.ColoredState }}"

input/prometheus.go

@@ -90,10 +90,6 @@ func shortenInstanceName(name string, pattern *regexp.Regexp) string {
 	return name
 }
 
-func (m PrometheusModule) GetEndpoint() string {
-	return "/prometheus"
-}
-
 func (m PrometheusModule) GetChannelList() []string {
 	return []string{m.defaultChannel}
 }

input/simple.go

@@ -23,10 +23,6 @@ func (m SimpleModule) GetChannelList() []string {
 	return []string{m.defaultChannel}
 }
 
-func (m SimpleModule) GetEndpoint() string {
-	return "/simple"
-}
-
 func (m SimpleModule) GetHandler() http.HandlerFunc {
 
 	return func(wr http.ResponseWriter, req *http.Request) {

main.go

@@ -4,6 +4,7 @@ import (
 	"flag"
 	"fmt"
 	"net/http"
+	"os"
 	"path"
 	"strings"
 	"time"
@@ -44,7 +45,8 @@ type Configuration struct {
 }
 
 type InputModule struct {
-	Enalbed string `yaml:"enabled"`
+	Type     string `yaml:"type"`
+	Endpoint string `yaml:"endpoint"`
 }
 
 func createModuleObject(name string) (input.Module, error) {
@@ -60,12 +62,36 @@ func createModuleObject(name string) (input.Module, error) {
 	case "icinga2":
 		m = &input.Icinga2Module{}
 	default:
-		e = fmt.Errorf("found configuration for unknown module: %q", name)
+		e = fmt.Errorf("ignoring configuration for unknown module: %q", name)
 	}
 
 	return m, e
 }
 
+func validateConfig(c Configuration) {
+	var foundErrors []string
+
+	for blockName, blockConfig := range c.Modules {
+		if blockConfig.Type == "" {
+			foundErrors = append(foundErrors, fmt.Sprintf("Block %q is missing its type", blockName))
+		}
+		if blockConfig.Endpoint == "" {
+			foundErrors = append(foundErrors, fmt.Sprintf("Block %q is missing its endpoint", blockName))
+		}
+	}
+
+	if len(foundErrors) > 0 {
+		log.Error("Found the following errors in the configuration:")
+		for _, e := range foundErrors {
+			log.Error(e)
+		}
+		os.Exit(1)
+	} else {
+		log.Info("Configuration parsed without errors")
+	}
+
+}
+
 func main() {
 	confDirPtr := flag.String("config", "/etc/cpthook.yml", "Path to the configfile")
 	flag.Parse()
@@ -85,24 +111,26 @@ func main() {
 	configureLogLevel()
 
 	var channelList = []string{}
-	var configurtaion = Configuration{}
+	var config = Configuration{}
 
-	err = viper.Unmarshal(&configurtaion)
+	err = viper.Unmarshal(&config)
 	if err != nil {
 		log.Fatal(err)
 	}
 
-	for moduleName := range configurtaion.Modules {
-		module, err := createModuleObject(moduleName)
+	validateConfig(config)
+
+	for blockName, blockConfig := range config.Modules {
+		module, err := createModuleObject(blockConfig.Type)
 		if err != nil {
 			log.Warn(err)
 			continue
 		}
-		log.Infof("Loaded module %q", moduleName)
-		configPath := fmt.Sprintf("modules.%s", moduleName)
+		log.Infof("Loaded block %q (Type %q, Endpoint %q)", blockName, blockConfig.Type, blockConfig.Endpoint)
+		configPath := fmt.Sprintf("modules.%s", blockName)
 		module.Init(viper.Sub(configPath), &inputChannel)
 		channelList = append(channelList, module.GetChannelList()...)
-		http.HandleFunc(module.GetEndpoint(), module.GetHandler())
+		http.HandleFunc(blockConfig.Endpoint, module.GetHandler())
 
 	}