feat: notification provider (#8)

Co-authored-by: Timo Behrendt <t.behrendt@t00n.de>
Co-committed-by: Timo Behrendt <t.behrendt@t00n.de>

pkg/notificationProvider/console/console.go

@@ -0,0 +1,16 @@
+package notificationProviderConsole
+
+import (
+	"fmt"
+)
+
+type NotificationProviderImplConsole struct{}
+
+func New() *NotificationProviderImplConsole {
+	return &NotificationProviderImplConsole{}
+}
+
+func (p *NotificationProviderImplConsole) SendNotification(title string, message string) error {
+	fmt.Printf("%s: %s\n", title, message)
+	return nil
+}

pkg/notificationProvider/gotify/gotify.go

@@ -0,0 +1,87 @@
+package notificationProviderGotify
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+)
+
+type NotificationProviderImplGotifyConfig struct {
+	Url      string `yaml:"url"`
+	Token    string `yaml:"token"`
+	Priority int    `yaml:"priority"`
+}
+
+type NotificationProviderImplGotify struct {
+	Url        url.URL
+	Token      string
+	Priority   int
+	HTTPClient *http.Client
+}
+
+func New(config NotificationProviderImplGotifyConfig) (*NotificationProviderImplGotify, error) {
+	if config.Url == "" {
+		return nil, fmt.Errorf("url is required")
+	}
+
+	url, err := url.Parse(config.Url)
+	if err != nil {
+		return nil, err
+	}
+
+	if config.Token == "" {
+		return nil, fmt.Errorf("token is required")
+	}
+
+	if config.Priority < 0 || config.Priority > 4 {
+		return nil, fmt.Errorf("priority must be between 0 and 4")
+	}
+
+	return &NotificationProviderImplGotify{
+		*url,
+		config.Token,
+		config.Priority,
+		&http.Client{},
+	}, nil
+}
+
+func (p *NotificationProviderImplGotify) SendNotification(title string, message string) error {
+	type GotifyMessage struct {
+		Message  string `json:"message"`
+		Title    string `json:"title"`
+		Priority int    `json:"priority"`
+	}
+
+	messageJson, err := json.Marshal(GotifyMessage{
+		message,
+		title,
+		p.Priority,
+	})
+	if err != nil {
+		return err
+	}
+
+	messageUrl := p.Url
+	messageUrl.JoinPath("message")
+	messageUrl.Query().Add("token", p.Token)
+
+	req, err := http.NewRequest("POST", messageUrl.String(), bytes.NewBuffer(messageJson))
+	if err != nil {
+		return err
+	}
+
+	req.Header.Set("Content-Type", "application/json")
+
+	res, err := p.HTTPClient.Do(req)
+	if err != nil {
+		return err
+	}
+
+	if res.StatusCode != 200 {
+		return fmt.Errorf("unexpected status code: %d", res.StatusCode)
+	}
+
+	return nil
+}

pkg/notificationProvider/gotify/gotify_test.go

@@ -0,0 +1,81 @@
+package notificationProviderGotify_test
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	gotify "realdnydns/pkg/notificationProvider/gotify"
+)
+
+func TestNew(t *testing.T) {
+	t.Run("URL is required", testNewEmptyUrl())
+	t.Run("Token is required", testNewEmptyToken())
+	t.Run("Priority must be between 0 and 4", testNewInvalidPriority())
+	t.Run("Sends POST request to url", testNewSendsPostRequest())
+}
+
+func testNewEmptyUrl() func(t *testing.T) {
+	return func(t *testing.T) {
+		_, err := gotify.New(gotify.NotificationProviderImplGotifyConfig{
+			Token:    "1234",
+			Priority: 1,
+		})
+
+		if err.Error() != "url is required" {
+			t.Errorf("Expected error 'url is required', got %v", err)
+		}
+	}
+}
+
+func testNewEmptyToken() func(t *testing.T) {
+	return func(t *testing.T) {
+		_, err := gotify.New(gotify.NotificationProviderImplGotifyConfig{
+			Url:      "http://localhost:1234",
+			Priority: 0,
+		})
+
+		if err.Error() != "token is required" {
+			t.Errorf("Expected error 'token is required', got %v", err)
+		}
+	}
+}
+
+func testNewInvalidPriority() func(t *testing.T) {
+	return func(t *testing.T) {
+		_, err := gotify.New(gotify.NotificationProviderImplGotifyConfig{
+			Url:      "http://localhost:1234",
+			Token:    "token",
+			Priority: 5,
+		})
+
+		if err.Error() != "priority must be between 0 and 4" {
+			t.Errorf("Expected error 'priority must be between 0 and 4', got %v", err)
+		}
+	}
+}
+
+func testNewSendsPostRequest() func(t *testing.T) {
+	return func(t *testing.T) {
+		mockServer := httptest.NewServer(http.HandlerFunc(
+			func(w http.ResponseWriter, r *http.Request) {
+				w.WriteHeader(200)
+			},
+		))
+		defer mockServer.Close()
+
+		provider, err := gotify.New(gotify.NotificationProviderImplGotifyConfig{
+			Url:      mockServer.URL,
+			Token:    "1234",
+			Priority: 0,
+		})
+		if err != nil {
+			t.Fatalf("New() returned unexpected error: %v", err)
+		}
+
+		err = provider.SendNotification("title", "message")
+		if err != nil {
+			t.Fatalf("SendNotification() returned unexpected error: %v", err)
+		}
+	}
+}

pkg/notificationProvider/notificationProvider.go

@@ -0,0 +1,5 @@
+package notificationProvider
+
+type NotificationProvider interface {
+	SendNotification(title string, message string) error
+}