Adding upstream version 0.8.9.

Signed-off-by: Daniel Baumann <daniel@debian.org>

pkg/services/discord/discord.go

@@ -0,0 +1,214 @@
+package discord
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"net/url"
+	"strings"
+
+	"github.com/nicholas-fedor/shoutrrr/pkg/format"
+	"github.com/nicholas-fedor/shoutrrr/pkg/services/standard"
+	"github.com/nicholas-fedor/shoutrrr/pkg/types"
+	"github.com/nicholas-fedor/shoutrrr/pkg/util"
+)
+
+const (
+	ChunkSize      = 2000 // Maximum size of a single message chunk
+	TotalChunkSize = 6000 // Maximum total size of all chunks
+	ChunkCount     = 10   // Maximum number of chunks allowed
+	MaxSearchRunes = 100  // Maximum number of runes to search for split position
+	HooksBaseURL   = "https://discord.com/api/webhooks"
+)
+
+var (
+	ErrUnknownAPIError  = errors.New("unknown error from Discord API")
+	ErrUnexpectedStatus = errors.New("unexpected response status code")
+	ErrInvalidURLPrefix = errors.New("URL must start with Discord webhook base URL")
+	ErrInvalidWebhookID = errors.New("invalid webhook ID")
+	ErrInvalidToken     = errors.New("invalid token")
+	ErrEmptyURL         = errors.New("empty URL provided")
+	ErrMalformedURL     = errors.New("malformed URL: missing webhook ID or token")
+)
+
+var limits = types.MessageLimit{
+	ChunkSize:      ChunkSize,
+	TotalChunkSize: TotalChunkSize,
+	ChunkCount:     ChunkCount,
+}
+
+// Service implements a Discord notification service.
+type Service struct {
+	standard.Standard
+	Config *Config
+	pkr    format.PropKeyResolver
+}
+
+// Send delivers a notification message to Discord.
+func (service *Service) Send(message string, params *types.Params) error {
+	var firstErr error
+
+	if service.Config.JSON {
+		postURL := CreateAPIURLFromConfig(service.Config)
+		if err := doSend([]byte(message), postURL); err != nil {
+			return fmt.Errorf("sending JSON message: %w", err)
+		}
+	} else {
+		batches := CreateItemsFromPlain(message, service.Config.SplitLines)
+		for _, items := range batches {
+			if err := service.sendItems(items, params); err != nil {
+				service.Log(err)
+
+				if firstErr == nil {
+					firstErr = err
+				}
+			}
+		}
+	}
+
+	if firstErr != nil {
+		return fmt.Errorf("failed to send discord notification: %w", firstErr)
+	}
+
+	return nil
+}
+
+// SendItems delivers message items with enhanced metadata and formatting to Discord.
+func (service *Service) SendItems(items []types.MessageItem, params *types.Params) error {
+	return service.sendItems(items, params)
+}
+
+func (service *Service) sendItems(items []types.MessageItem, params *types.Params) error {
+	config := *service.Config
+	if err := service.pkr.UpdateConfigFromParams(&config, params); err != nil {
+		return fmt.Errorf("updating config from params: %w", err)
+	}
+
+	payload, err := CreatePayloadFromItems(items, config.Title, config.LevelColors())
+	if err != nil {
+		return fmt.Errorf("creating payload: %w", err)
+	}
+
+	payload.Username = config.Username
+	payload.AvatarURL = config.Avatar
+
+	payloadBytes, err := json.Marshal(payload)
+	if err != nil {
+		return fmt.Errorf("marshaling payload to JSON: %w", err)
+	}
+
+	postURL := CreateAPIURLFromConfig(&config)
+
+	return doSend(payloadBytes, postURL)
+}
+
+// CreateItemsFromPlain converts plain text into MessageItems suitable for Discord's webhook payload.
+func CreateItemsFromPlain(plain string, splitLines bool) [][]types.MessageItem {
+	var batches [][]types.MessageItem
+
+	if splitLines {
+		return util.MessageItemsFromLines(plain, limits)
+	}
+
+	for {
+		items, omitted := util.PartitionMessage(plain, limits, MaxSearchRunes)
+		batches = append(batches, items)
+
+		if omitted == 0 {
+			break
+		}
+
+		plain = plain[len(plain)-omitted:]
+	}
+
+	return batches
+}
+
+// Initialize configures the service with a URL and logger.
+func (service *Service) Initialize(configURL *url.URL, logger types.StdLogger) error {
+	service.SetLogger(logger)
+	service.Config = &Config{}
+	service.pkr = format.NewPropKeyResolver(service.Config)
+
+	if err := service.pkr.SetDefaultProps(service.Config); err != nil {
+		return fmt.Errorf("setting default properties: %w", err)
+	}
+
+	if err := service.Config.SetURL(configURL); err != nil {
+		return fmt.Errorf("setting config URL: %w", err)
+	}
+
+	return nil
+}
+
+// GetID provides the identifier for this service.
+func (service *Service) GetID() string {
+	return Scheme
+}
+
+// CreateAPIURLFromConfig builds a POST URL from the Discord configuration.
+func CreateAPIURLFromConfig(config *Config) string {
+	if config.WebhookID == "" || config.Token == "" {
+		return "" // Invalid cases are caught in doSend
+	}
+	// Trim whitespace to prevent malformed URLs
+	webhookID := strings.TrimSpace(config.WebhookID)
+	token := strings.TrimSpace(config.Token)
+
+	baseURL := fmt.Sprintf("%s/%s/%s", HooksBaseURL, webhookID, token)
+
+	if config.ThreadID != "" {
+		// Append thread_id as a query parameter
+		query := url.Values{}
+		query.Set("thread_id", strings.TrimSpace(config.ThreadID))
+
+		return baseURL + "?" + query.Encode()
+	}
+
+	return baseURL
+}
+
+// doSend executes an HTTP POST request to deliver the payload to Discord.
+//
+//nolint:gosec,noctx
+func doSend(payload []byte, postURL string) error {
+	if postURL == "" {
+		return ErrEmptyURL
+	}
+
+	parsedURL, err := url.ParseRequestURI(postURL)
+	if err != nil {
+		return fmt.Errorf("invalid URL: %w", err)
+	}
+
+	if !strings.HasPrefix(parsedURL.String(), HooksBaseURL) {
+		return ErrInvalidURLPrefix
+	}
+
+	parts := strings.Split(strings.TrimPrefix(postURL, HooksBaseURL+"/"), "/")
+	if len(parts) != 2 || parts[0] == "" || parts[1] == "" {
+		return ErrMalformedURL
+	}
+
+	webhookID := strings.TrimSpace(parts[0])
+	token := strings.TrimSpace(parts[1])
+	safeURL := fmt.Sprintf("%s/%s/%s", HooksBaseURL, webhookID, token)
+
+	res, err := http.Post(safeURL, "application/json", bytes.NewBuffer(payload))
+	if err != nil {
+		return fmt.Errorf("making HTTP POST request: %w", err)
+	}
+
+	if res == nil {
+		return ErrUnknownAPIError
+	}
+	defer res.Body.Close()
+
+	if res.StatusCode != http.StatusNoContent {
+		return fmt.Errorf("%w: %s", ErrUnexpectedStatus, res.Status)
+	}
+
+	return nil
+}