feat: implement ntfy-discord bridge in Go

- SSE subscription to ntfy with auto-reconnect
- Discord webhook integration with embed formatting
- Priority to color mapping, tag to emoji conversion
- Native HashiCorp Vault support (Kubernetes + token auth)
- Hot reload secrets via fsnotify or Vault polling
- Prometheus metrics (/metrics endpoint)
- Health/ready endpoints for Kubernetes probes
- Comprehensive unit tests and fuzz tests
- Multi-stage Docker build (~10MB scratch image)
- CI/CD pipeline for Gitea Actions

internal/discord/webhook_test.go

@@ -0,0 +1,260 @@
+package discord
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"git.daviestechlabs.io/daviestechlabs/ntfy-discord/internal/ntfy"
+)
+
+func TestClient_Send(t *testing.T) {
+	tests := []struct {
+		name       string
+		msg        ntfy.Message
+		wantStatus int
+		wantErr    bool
+	}{
+		{
+			name: "successful send",
+			msg: ntfy.Message{
+				ID:       "test-id",
+				Topic:    "alerts",
+				Title:    "Test Alert",
+				Message:  "This is a test message",
+				Priority: 3,
+				Time:     time.Now().Unix(),
+			},
+			wantStatus: http.StatusNoContent,
+			wantErr:    false,
+		},
+		{
+			name: "high priority message",
+			msg: ntfy.Message{
+				ID:       "high-priority",
+				Topic:    "urgent",
+				Title:    "Urgent Alert",
+				Message:  "Critical issue detected",
+				Priority: 5,
+				Tags:     []string{"warning", "fire"},
+			},
+			wantStatus: http.StatusNoContent,
+			wantErr:    false,
+		},
+		{
+			name: "server error",
+			msg: ntfy.Message{
+				ID:    "error-test",
+				Topic: "test",
+			},
+			wantStatus: http.StatusInternalServerError,
+			wantErr:    true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var receivedPayload WebhookPayload
+
+			server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				if r.Method != http.MethodPost {
+					t.Errorf("expected POST, got %s", r.Method)
+				}
+				if r.Header.Get("Content-Type") != "application/json" {
+					t.Errorf("expected application/json, got %s", r.Header.Get("Content-Type"))
+				}
+
+				if err := json.NewDecoder(r.Body).Decode(&receivedPayload); err != nil {
+					t.Errorf("failed to decode payload: %v", err)
+				}
+
+				w.WriteHeader(tt.wantStatus)
+			}))
+			defer server.Close()
+
+			client := NewClient()
+			err := client.Send(context.Background(), server.URL, tt.msg)
+
+			if (err != nil) != tt.wantErr {
+				t.Errorf("Send() error = %v, wantErr %v", err, tt.wantErr)
+			}
+
+			if !tt.wantErr && len(receivedPayload.Embeds) != 1 {
+				t.Errorf("expected 1 embed, got %d", len(receivedPayload.Embeds))
+			}
+		})
+	}
+}
+
+func TestClient_Send_NoWebhookURL(t *testing.T) {
+	client := NewClient()
+	err := client.Send(context.Background(), "", ntfy.Message{})
+
+	if err == nil {
+		t.Error("expected error for empty webhook URL")
+	}
+}
+
+func TestClient_buildEmbed(t *testing.T) {
+	client := NewClient()
+
+	tests := []struct {
+		name      string
+		msg       ntfy.Message
+		wantColor int
+		wantEmoji string
+	}{
+		{
+			name: "default priority",
+			msg: ntfy.Message{
+				Title:    "Test",
+				Message:  "Hello",
+				Priority: 3,
+			},
+			wantColor: 3066993, // Blue
+			wantEmoji: "",
+		},
+		{
+			name: "max priority with warning tag",
+			msg: ntfy.Message{
+				Title:    "Alert",
+				Message:  "Critical",
+				Priority: 5,
+				Tags:     []string{"warning"},
+			},
+			wantColor: 15158332, // Red
+			wantEmoji: "⚠️",
+		},
+		{
+			name: "low priority",
+			msg: ntfy.Message{
+				Title:    "Info",
+				Message:  "Low priority",
+				Priority: 2,
+			},
+			wantColor: 9807270, // Gray
+			wantEmoji: "",
+		},
+		{
+			name: "with check tag",
+			msg: ntfy.Message{
+				Title:    "Success",
+				Message:  "Completed",
+				Priority: 3,
+				Tags:     []string{"check", "success"},
+			},
+			wantColor: 3066993,
+			wantEmoji: "✅",
+		},
+		{
+			name: "no title uses topic",
+			msg: ntfy.Message{
+				Topic:   "alerts",
+				Message: "No title",
+			},
+			wantColor: 3066993,
+			wantEmoji: "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			embed := client.buildEmbed(tt.msg)
+
+			if embed.Color != tt.wantColor {
+				t.Errorf("Color = %d, want %d", embed.Color, tt.wantColor)
+			}
+
+			if tt.wantEmoji != "" {
+				if len(embed.Title) < 2 || embed.Title[:len(tt.wantEmoji)] != tt.wantEmoji {
+					t.Errorf("Title should start with emoji %s, got %s", tt.wantEmoji, embed.Title)
+				}
+			}
+
+			if embed.Description != tt.msg.Message {
+				t.Errorf("Description = %s, want %s", embed.Description, tt.msg.Message)
+			}
+		})
+	}
+}
+
+func TestClient_extractEmoji(t *testing.T) {
+	client := NewClient()
+
+	tests := []struct {
+		name string
+		tags []string
+		want string
+	}{
+		{"warning tag", []string{"warning"}, "⚠️"},
+		{"check tag", []string{"check"}, "✅"},
+		{"fire tag", []string{"fire"}, "🔥"},
+		{"rocket tag", []string{"rocket"}, "🚀"},
+		{"unknown tag", []string{"unknown"}, ""},
+		{"empty tags", []string{}, ""},
+		{"multiple tags first match", []string{"unknown", "fire", "warning"}, "🔥"},
+		{"case insensitive", []string{"WARNING"}, "⚠️"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := client.extractEmoji(tt.tags)
+			if got != tt.want {
+				t.Errorf("extractEmoji(%v) = %s, want %s", tt.tags, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestPriorityColors(t *testing.T) {
+	expected := map[int]int{
+		1: 12370112, // Light Gray
+		2: 9807270,  // Gray
+		3: 3066993,  // Blue
+		4: 15105570, // Orange
+		5: 15158332, // Red
+	}
+
+	for priority, color := range expected {
+		if priorityColors[priority] != color {
+			t.Errorf("priorityColors[%d] = %d, want %d", priority, priorityColors[priority], color)
+		}
+	}
+}
+
+func TestWebhookPayload_JSON(t *testing.T) {
+	payload := WebhookPayload{
+		Embeds: []Embed{
+			{
+				Title:       "Test",
+				Description: "Hello World",
+				Color:       3066993,
+				Fields: []Field{
+					{Name: "Topic", Value: "alerts", Inline: true},
+				},
+				Footer: &Footer{Text: "ntfy"},
+			},
+		},
+	}
+
+	data, err := json.Marshal(payload)
+	if err != nil {
+		t.Fatalf("failed to marshal: %v", err)
+	}
+
+	var decoded WebhookPayload
+	if err := json.Unmarshal(data, &decoded); err != nil {
+		t.Fatalf("failed to unmarshal: %v", err)
+	}
+
+	if len(decoded.Embeds) != 1 {
+		t.Errorf("expected 1 embed, got %d", len(decoded.Embeds))
+	}
+
+	if decoded.Embeds[0].Title != "Test" {
+		t.Errorf("Title = %s, want Test", decoded.Embeds[0].Title)
+	}
+}