refactor: split into smaller files

Author: kkweon

.gitignore

@@ -1,3 +1,4 @@
 alertmanager-discord
 alertmanager-discord.darwin
 alertmanager-discord.linux
+/.idea/

README.md

@@ -1,10 +1,10 @@
+This is a fork of https://github.com/benjojo/alertmanager-discord to enable a few more features.
+
 alertmanager-discord
 ===
 
 Give this a webhook (with the DISCORD_WEBHOOK environment variable) and point it as a webhook on alertmanager, and it will post your alerts into a discord channel for you as they trigger:
 
-![](/.github/demo-new.png)
-
 ## Warning
 
 This program is not a replacement to alertmanager, it accepts webhooks from alertmanager, not prometheus.
@@ -19,11 +19,6 @@ alerting:                 receivers:
   - static_configs:         webhook_configs:                   - DISCORD_WEBHOOK=https://discordapp.com/api/we...
     - targets:              - url: 'http://localhost:9094'  
        - 127.0.0.1:9093   
-
-
-
-
-
 ```
 
 ## Example alertmanager config:
@@ -56,4 +51,8 @@ receivers:
 
 ## Docker
 
-If you run a fancy docker/k8s infra, you can find the docker hub repo here: https://hub.docker.com/r/benjojo/alertmanager-discord/
+See https://github.com/orgs/codingpot/packages/container/package/alertmanager-discord for the latest image.
+
+```dockerfile
+FROM ghcr.io/codingpot/alertmanager-discord:v0
+```

alertman/alertman.go

@@ -0,0 +1,59 @@
+package alertman
+
+import "encoding/json"
+
+type AlertManAlert struct {
+	Annotations struct {
+		Description string `json:"description"`
+		Summary     string `json:"summary"`
+	} `json:"annotations"`
+	EndsAt       string            `json:"endsAt"`
+	GeneratorURL string            `json:"generatorURL"`
+	Labels       map[string]string `json:"labels"`
+	StartsAt     string            `json:"startsAt"`
+	Status       string            `json:"status"`
+}
+
+type AlertManOut struct {
+	Alerts            []AlertManAlert `json:"alerts"`
+	CommonAnnotations struct {
+		Summary string `json:"summary"`
+	} `json:"commonAnnotations"`
+	CommonLabels struct {
+		Alertname string `json:"alertname"`
+	} `json:"commonLabels"`
+	ExternalURL string `json:"externalURL"`
+	GroupKey    string `json:"groupKey"`
+	GroupLabels struct {
+		Alertname string `json:"alertname"`
+	} `json:"groupLabels"`
+	Receiver string `json:"receiver"`
+	Status   string `json:"status"`
+	Version  string `json:"version"`
+}
+
+type rawPromAlert struct {
+	Annotations struct {
+		Description string `json:"description"`
+		Summary     string `json:"summary"`
+	} `json:"annotations"`
+	EndsAt       string            `json:"endsAt"`
+	GeneratorURL string            `json:"generatorURL"`
+	Labels       map[string]string `json:"labels"`
+	StartsAt     string            `json:"startsAt"`
+	Status       string            `json:"status"`
+}
+
+func IsRawPromAlert(b []byte) bool {
+	alertTest := make([]rawPromAlert, 0)
+	err := json.Unmarshal(b, &alertTest)
+	if err == nil {
+		if len(alertTest) != 0 {
+			if alertTest[0].Status == "" {
+				// Ok it's more than likely then
+				return true
+			}
+		}
+	}
+	return false
+}

detect-misconfig.go

@@ -0,0 +1,112 @@
+package discord
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"github.com/codingpot/alertmanager-discord/alertman"
+	"github.com/sirupsen/logrus"
+	"net/http"
+	"strings"
+)
+
+// Discord color values
+const (
+	ColorRed   = 0x992D22
+	ColorGreen = 0x2ECC71
+	ColorGrey  = 0x95A5A6
+)
+
+type DiscordOut struct {
+	Content string         `json:"content"`
+	Embeds  []DiscordEmbed `json:"embeds"`
+}
+
+type DiscordEmbed struct {
+	Title       string              `json:"title"`
+	Description string              `json:"description"`
+	Color       int                 `json:"color"`
+	Fields      []DiscordEmbedField `json:"fields"`
+}
+
+type DiscordEmbedField struct {
+	Name  string `json:"name"`
+	Value string `json:"value"`
+}
+
+func SendWebhook(amo *alertman.AlertManOut, discordWebhookURL string) {
+	groupedAlerts := make(map[string][]alertman.AlertManAlert)
+
+	for _, alert := range amo.Alerts {
+		groupedAlerts[alert.Status] = append(groupedAlerts[alert.Status], alert)
+	}
+
+	for status, alerts := range groupedAlerts {
+		DO := DiscordOut{}
+
+		RichEmbed := DiscordEmbed{
+			Title:       fmt.Sprintf("[%s:%d] %s", strings.ToUpper(status), len(alerts), amo.CommonLabels.Alertname),
+			Description: amo.CommonAnnotations.Summary,
+			Color:       ColorGrey,
+			Fields:      []DiscordEmbedField{},
+		}
+
+		if status == "firing" {
+			RichEmbed.Color = ColorRed
+		} else if status == "resolved" {
+			RichEmbed.Color = ColorGreen
+		}
+
+		if amo.CommonAnnotations.Summary != "" {
+			DO.Content = fmt.Sprintf(" === %s === \n", amo.CommonAnnotations.Summary)
+		}
+
+		for _, alert := range alerts {
+			realname := alert.Labels["instance"]
+			if strings.Contains(realname, "localhost") && alert.Labels["exported_instance"] != "" {
+				realname = alert.Labels["exported_instance"]
+			}
+
+			RichEmbed.Fields = append(RichEmbed.Fields, DiscordEmbedField{
+				Name:  fmt.Sprintf("[%s]: %s on %s", strings.ToUpper(status), alert.Labels["alertname"], realname),
+				Value: alert.Annotations.Description,
+			})
+		}
+
+		DO.Embeds = []DiscordEmbed{RichEmbed}
+
+		DOD, _ := json.Marshal(DO)
+		http.Post(discordWebhookURL, "application/json", bytes.NewReader(DOD))
+	}
+}
+
+func SendRawPromAlertWarn(discordWebhookURL string) {
+	badString := `This program is suppose to be fed by alertmanager.` + "\n" +
+		`It is not a replacement for alertmanager, it is a ` + "\n" +
+		`webhook target for it. Please read the README.md  ` + "\n" +
+		`for guidance on how to configure it for alertmanager` + "\n" +
+		`or https://prometheus.io/docs/alerting/latest/configuration/#webhook_config`
+
+	logrus.Print(`/!\ -- You have misconfigured this software -- /!\`)
+	logrus.Print(`--- --                                      -- ---`)
+	logrus.Print(badString)
+
+	DO := DiscordOut{
+		Content: "",
+		Embeds: []DiscordEmbed{
+			{
+				Title:       "You have misconfigured this software",
+				Description: badString,
+				Color:       ColorGrey,
+				Fields:      []DiscordEmbedField{},
+			},
+		},
+	}
+
+	DOD, _ := json.Marshal(DO)
+	_, err := http.Post(discordWebhookURL, "application/json", bytes.NewReader(DOD))
+	if err != nil {
+		logrus.Printf("failed to sned the alert")
+		return
+	}
+}

discord/discord.go

@@ -1,3 +1,9 @@
 module github.com/codingpot/alertmanager-discord
 
 go 1.16
+
+require (
+	github.com/go-chi/chi/v5 v5.0.3
+	github.com/sirupsen/logrus v1.8.1
+	github.com/stretchr/testify v1.2.2
+)

go.mod

@@ -0,0 +1,12 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/go-chi/chi/v5 v5.0.3 h1:khYQBdPivkYG1s1TAzDQG1f6eX4kD2TItYVZexL5rS4=
+github.com/go-chi/chi/v5 v5.0.3/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNITLSKoi8=
+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 v1.8.1 h1:dJKuHgqk1NNQlqoA6BTlM1Wf9DOH3NBjQyu0h9+AZZE=
+github.com/sirupsen/logrus v1.8.1/go.mod h1:yWOB1SBYBC5VeMP7gHvWumXLIWorT60ONWic61uBYv0=
+github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
+github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+golang.org/x/sys v0.0.0-20191026070338-33540a1f6037 h1:YyJpGZS1sBuBCzLAR1VEpK193GlqGZbnPFnPV/5Rsb4=
+golang.org/x/sys v0.0.0-20191026070338-33540a1f6037/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=

go.sum

@@ -0,0 +1,65 @@
+package internal
+
+import (
+	"encoding/json"
+	"github.com/codingpot/alertmanager-discord/alertman"
+	"github.com/codingpot/alertmanager-discord/discord"
+	"github.com/go-chi/chi/v5"
+	"github.com/go-chi/chi/v5/middleware"
+	"github.com/sirupsen/logrus"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"net/url"
+	"regexp"
+)
+
+func ValidateWebhookURL(webhookURL string) {
+	if webhookURL == "" {
+		log.Fatalf("Environment variable 'DISCORD_WEBHOOK' or CLI parameter 'webhook.url' not found.")
+	}
+	_, err := url.Parse(webhookURL)
+	if err != nil {
+		log.Fatalf("The Discord WebHook URL doesn't seem to be a valid URL.")
+	}
+
+	re := regexp.MustCompile(`https://discord(?:app)?.com/api/webhooks/[0-9]{18}/[a-zA-Z0-9_-]+`)
+	if ok := re.Match([]byte(webhookURL)); !ok {
+		log.Printf("The Discord WebHook URL doesn't seem to be valid.")
+	}
+}
+
+func NewRouter(discordWebhookURL string) *chi.Mux {
+	r := chi.NewRouter()
+	r.Use(middleware.Logger, middleware.Heartbeat("/healthcheck"))
+
+	r.Post("/", func(w http.ResponseWriter, r *http.Request) {
+		b, err := ioutil.ReadAll(r.Body)
+		if err != nil {
+			http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
+			return
+		}
+
+		var amo alertman.AlertManOut
+		err = json.Unmarshal(b, &amo)
+		if err != nil {
+			if alertman.IsRawPromAlert(b) {
+				discord.SendRawPromAlertWarn(discordWebhookURL)
+				return
+			}
+
+			if len(b) > 1024 {
+				logrus.Printf("Failed to unpack inbound alert request - %s...", string(b[:1023]))
+
+			} else {
+				logrus.Printf("Failed to unpack inbound alert request - %s", string(b))
+			}
+
+			return
+		}
+
+		discord.SendWebhook(&amo, discordWebhookURL)
+	})
+
+	return r
+}

internal/internal.go

@@ -0,0 +1,19 @@
+package internal
+
+import (
+	"github.com/stretchr/testify/assert"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestNewRouter_Healthcheck(t *testing.T) {
+	r := NewRouter("https://0.0.0.0")
+
+	server := httptest.NewServer(r)
+	defer server.Close()
+
+	get, err := http.Get(server.URL + "/healthcheck")
+	assert.NoError(t, err)
+	assert.Equal(t, http.StatusOK, get.StatusCode)
+}