feat: add healthchecks.io service

README.md

@@ -87,6 +87,36 @@ It uses zerolog levels (from highest to lowest):
 * trace (zerolog.TraceLevel, -1)
 
 ### Modules
+#### Healthchecks
+Uses the [Healthchecks.io](https://healthchecks.io) service to check whether `discord-bot` is online or not.  
+It can triggers alerts on several systems if it is down.  
+
+**If you don't want to use it, leave `uuid` empty.**  
+
+You can use your own version by using a custom `base_url`.  
+
+JSON configuration used:  
+```json
+"healthchecks": {
+  "base_url": "https://hc-ping.com/",
+  "uuid": "00000000-0000-0000-0000-000000000000",
+  "started_message": "discord-bot started",
+  "failed_message": "discord-bot failed"
+}
+```
+
+| JSON Parameter  | Mandatory | Type   | Default value        | Description                                                       |
+| --------------- | --------- | ------ | -------------------- | ----------------------------------------------------------------- |
+| base_url        | NO        | string | https://hc-ping.com/ | url to ping, by default use the healthchecks service              |
+| uuid            | YES       | string |                      | uuid, on healthchecks dashboard it's after `https://hc-ping.com/` |
+| started_message | NO        | string | discord-bot started  | message sent to healthchecks when discord-bot starts              |
+| failed_message  | NO        | string | discord-bot failed   | message sent to healthchecks when discord-bot stops               |
+
+##### How it works?
+Each time you start `discord-bot`, the healthchecks module will check the configuration in `config.json`.  
+Then, when all modules have been started, it sends a `Start` ping message to indicate that the discord-bot is up and running.  
+Finally, if `discord-bot` receives a signal from the OS to terminate the program, it will send a `Fail` ping message.
+
 #### Welcome
 Define the user's role when using an emoji.  
 You can define one or more messages in only one channel.  

config.template.json

@@ -23,6 +23,12 @@
           "purge_below_count_members_not_in_guild": 10
         }
       ]
+    },
+    "healthchecks": {
+      "base_url": "",
+      "uuid": "",
+      "started_message": "",
+      "failed_message": ""
     }
   }
 }

configuration/configuration.go

@@ -11,6 +11,7 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/blueprintue/discord-bot/healthchecks"
 	"github.com/blueprintue/discord-bot/welcome"
 )
 
@@ -42,7 +43,8 @@ type Log struct {
 }
 
 type Modules struct {
-	WelcomeConfiguration welcome.Configuration `json:"welcome"`
+	WelcomeConfiguration     welcome.Configuration      `json:"welcome"`
+	HealthcheckConfiguration healthchecks.Configuration `json:"healthchecks"`
 }
 
 // ReadConfiguration read `config.json` file and update values with env if found.

go.mod

@@ -4,6 +4,7 @@ go 1.22
 
 require (
 	github.com/bwmarrin/discordgo v0.27.1
+	github.com/crazy-max/gohealthchecks v0.4.1
 	github.com/ilya1st/rotatewriter v0.0.0-20171126183947-3df0c1a3ed6d
 	github.com/rs/zerolog v1.32.0
 	github.com/stretchr/testify v1.8.4

go.sum

@@ -1,6 +1,8 @@
 github.com/bwmarrin/discordgo v0.27.1 h1:ib9AIc/dom1E/fSIulrBwnez0CToJE113ZGt4HoliGY=
 github.com/bwmarrin/discordgo v0.27.1/go.mod h1:NJZpH+1AfhIcyQsPeuBKsUtYrRnjkyu0kIVMCHkZtRY=
 github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
+github.com/crazy-max/gohealthchecks v0.4.1 h1:gbjZzF/GxwDyP78u37B2/c2iQfq8BEjAHS3eBLM6FcQ=
+github.com/crazy-max/gohealthchecks v0.4.1/go.mod h1:gkT8QSdEXZJahyswdTGDbd+q20fWm0DmWW7TWBNtgJg=
 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/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=

healthchecks/healthcheck.go

@@ -0,0 +1,133 @@
+package healthchecks
+
+import (
+	"context"
+	"fmt"
+	"net/url"
+	"strings"
+
+	"github.com/crazy-max/gohealthchecks"
+	"github.com/rs/zerolog/log"
+)
+
+type Configuration struct {
+	BaseURL        string `json:"base_url"`
+	UUID           string `json:"uuid"`
+	StartedMessage string `json:"started_message"`
+	FailedMessage  string `json:"failed_message"`
+}
+
+type Manager struct {
+	client         *gohealthchecks.Client
+	baseURL        *url.URL
+	uuid           string
+	startedMessage string
+	failedMessage  string
+}
+
+func NewHealthchecksManager(
+	config Configuration,
+) *Manager {
+	manager := &Manager{}
+
+	log.Info().Msg("Checking configuration for Healthchecks")
+
+	if !manager.hasValidConfigurationInFile(config) {
+		return nil
+	}
+
+	return manager
+}
+
+func (m *Manager) hasValidConfigurationInFile(config Configuration) bool {
+	baseRawURL := config.BaseURL
+	if baseRawURL == "" {
+		log.Info().
+			Msg("BaseURL is empty, use default URL https://hc-ping.com/")
+
+		baseRawURL = "https://hc-ping.com/"
+	}
+
+	baseURL, err := url.Parse(baseRawURL)
+	if err != nil {
+		log.Error().
+			Err(err).
+			Str("base_url", baseRawURL).
+			Msg("BaseURL is invalid")
+
+		return false
+	}
+
+	if !strings.HasSuffix(baseURL.Path, "/") {
+		baseURL.Path += "/"
+	}
+
+	m.baseURL = baseURL
+
+	if config.UUID == "" {
+		log.Error().
+			Msg("UUID is empty")
+
+		return false
+	}
+
+	m.uuid = config.UUID
+
+	m.startedMessage = config.StartedMessage
+	if m.startedMessage == "" {
+		log.Info().
+			Msg(`StartedMessage is empty, use default "discord-bot started"`)
+
+		m.startedMessage = "discord-bot started"
+	}
+
+	m.failedMessage = config.FailedMessage
+	if m.failedMessage == "" {
+		log.Info().
+			Msg(`FailedMessage is empty, use default "discord-bot stopped"`)
+
+		m.failedMessage = "discord-bot stopped"
+	}
+
+	return true
+}
+
+func (m *Manager) Run() error {
+	m.client = gohealthchecks.NewClient(
+		&gohealthchecks.ClientOptions{
+			BaseURL: m.baseURL,
+		},
+	)
+
+	err := m.client.Start(
+		context.Background(),
+		gohealthchecks.PingingOptions{
+			UUID: m.uuid,
+			Logs: m.startedMessage,
+		},
+	)
+	if err != nil {
+		log.Error().
+			Err(err).
+			Msg("Could not send Start HealthChecks client")
+
+		return fmt.Errorf("%w", err)
+	}
+
+	return nil
+}
+
+func (m *Manager) Fail() {
+	err := m.client.Fail(
+		context.Background(),
+		gohealthchecks.PingingOptions{
+			UUID: m.uuid,
+			Logs: m.failedMessage,
+		},
+	)
+	if err != nil {
+		log.Error().
+			Err(err).
+			Msg("Could not send Fail HealthChecks client")
+	}
+}

healthchecks/healthchecks_fail_test.go

@@ -0,0 +1,89 @@
+//nolint:paralleltest
+package healthchecks_test
+
+import (
+	"bytes"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/blueprintue/discord-bot/healthchecks"
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/log"
+	"github.com/stretchr/testify/require"
+)
+
+func TestFail(t *testing.T) {
+	var bufferLogs bytes.Buffer
+	log.Logger = zerolog.New(&bufferLogs).Level(zerolog.TraceLevel).With().Logger()
+
+	currentRequestIdx := 0
+
+	svr := httptest.NewServer(http.HandlerFunc(func(res http.ResponseWriter, req *http.Request) {
+		if currentRequestIdx == 0 {
+			require.Equal(t, "/00000000-0000-0000-0000-000000000000/start", req.RequestURI)
+			startedMessage, err := io.ReadAll(req.Body)
+			require.NoError(t, err)
+			require.Equal(t, "starts", string(startedMessage))
+		} else {
+			require.Equal(t, "/00000000-0000-0000-0000-000000000000/fail", req.RequestURI)
+			failedMessage, err := io.ReadAll(req.Body)
+			require.NoError(t, err)
+			require.Equal(t, "stops", string(failedMessage))
+		}
+
+		currentRequestIdx++
+
+		res.WriteHeader(http.StatusOK)
+	}))
+	defer svr.Close()
+
+	healthchecksManager := healthchecks.NewHealthchecksManager(healthchecks.Configuration{
+		BaseURL:        svr.URL,
+		UUID:           "00000000-0000-0000-0000-000000000000",
+		StartedMessage: "starts",
+		FailedMessage:  "stops",
+	})
+	require.NotNil(t, healthchecksManager)
+
+	err := healthchecksManager.Run()
+	require.NoError(t, err)
+
+	bufferLogs.Reset()
+
+	healthchecksManager.Fail()
+
+	parts := strings.Split(bufferLogs.String(), "\n")
+	require.Equal(t, ``, parts[0])
+}
+
+func TestFail_Errors(t *testing.T) {
+	var bufferLogs bytes.Buffer
+	log.Logger = zerolog.New(&bufferLogs).Level(zerolog.TraceLevel).With().Logger()
+
+	svr := httptest.NewServer(http.HandlerFunc(func(res http.ResponseWriter, _ *http.Request) {
+		res.WriteHeader(http.StatusInternalServerError)
+	}))
+	defer svr.Close()
+
+	healthchecksManager := healthchecks.NewHealthchecksManager(healthchecks.Configuration{
+		BaseURL:        svr.URL,
+		UUID:           "00000000-0000-0000-0000-000000000000",
+		StartedMessage: "starts",
+		FailedMessage:  "stops",
+	})
+	require.NotNil(t, healthchecksManager)
+
+	err := healthchecksManager.Run()
+	require.Error(t, err)
+
+	bufferLogs.Reset()
+
+	healthchecksManager.Fail()
+
+	parts := strings.Split(bufferLogs.String(), "\n")
+	require.Equal(t, `{"level":"error","error":"HTTP error 500","message":"Could not send Fail HealthChecks client"}`, parts[0])
+	require.Equal(t, ``, parts[1])
+}

healthchecks/healthchecks_run_test.go

@@ -0,0 +1,74 @@
+//nolint:paralleltest
+package healthchecks_test
+
+import (
+	"bytes"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/blueprintue/discord-bot/healthchecks"
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/log"
+	"github.com/stretchr/testify/require"
+)
+
+func TestRun(t *testing.T) {
+	var bufferLogs bytes.Buffer
+	log.Logger = zerolog.New(&bufferLogs).Level(zerolog.TraceLevel).With().Logger()
+
+	svr := httptest.NewServer(http.HandlerFunc(func(res http.ResponseWriter, req *http.Request) {
+		require.Equal(t, "/00000000-0000-0000-0000-000000000000/start", req.RequestURI)
+		startedMessage, err := io.ReadAll(req.Body)
+		require.NoError(t, err)
+		require.Equal(t, "starts", string(startedMessage))
+
+		res.WriteHeader(http.StatusOK)
+	}))
+	defer svr.Close()
+
+	healthchecksManager := healthchecks.NewHealthchecksManager(healthchecks.Configuration{
+		BaseURL:        svr.URL,
+		UUID:           "00000000-0000-0000-0000-000000000000",
+		StartedMessage: "starts",
+		FailedMessage:  "stops",
+	})
+	require.NotNil(t, healthchecksManager)
+
+	bufferLogs.Reset()
+
+	err := healthchecksManager.Run()
+	require.NoError(t, err)
+
+	parts := strings.Split(bufferLogs.String(), "\n")
+	require.Equal(t, ``, parts[0])
+}
+
+func TestRun_Errors(t *testing.T) {
+	var bufferLogs bytes.Buffer
+	log.Logger = zerolog.New(&bufferLogs).Level(zerolog.TraceLevel).With().Logger()
+
+	svr := httptest.NewServer(http.HandlerFunc(func(res http.ResponseWriter, _ *http.Request) {
+		res.WriteHeader(http.StatusInternalServerError)
+	}))
+	defer svr.Close()
+
+	healthchecksManager := healthchecks.NewHealthchecksManager(healthchecks.Configuration{
+		BaseURL:        svr.URL,
+		UUID:           "00000000-0000-0000-0000-000000000000",
+		StartedMessage: "starts",
+		FailedMessage:  "stops",
+	})
+	require.NotNil(t, healthchecksManager)
+
+	bufferLogs.Reset()
+
+	err := healthchecksManager.Run()
+	require.Error(t, err)
+
+	parts := strings.Split(bufferLogs.String(), "\n")
+	require.Equal(t, `{"level":"error","error":"HTTP error 500","message":"Could not send Start HealthChecks client"}`, parts[0])
+	require.Equal(t, ``, parts[1])
+}