feat(notifications): ntfy/Gotify push channels with live delivery (#69)

Per-user notification_channels (ntfy + Gotify): every
insertUserNotification now fans out best-effort to enabled channels —
deployment/backup/security/agent alerts reach the user's phone via the
ntfy app with zero extra infrastructure.

- POST/GET/DELETE /notifications/channels + POST .../:id/test which
  pushes a real probe so misconfiguration surfaces before alerts depend
  on it (502 DELIVERY_FAILED on endpoint errors).
- ntfy: POST to endpoint (topic in path), Title/Tags headers, optional
  Bearer token. Gotify: POST {endpoint}/message?token=...
- Delivery is best-effort by design — a dead relay never breaks the
  producing flow; one shared 5s-timeout client.
- CLI `notifications channels list|add|test|remove`, MCP tools,
  OpenAPI paths + NotificationChannel schema.
- Web settings "Push notifications" section and a Push channels card on
  the mobile notifications tab (add/test/remove).

Verified live: channel CRUD, test-ping hit a recording endpoint with
correct headers/body, and a real deployment fanned out "Deployment
succeeded" through the channel end-to-end.

Generated with [Devin](https://devin.ai)

Co-authored-by: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

app/backend/internal/api/notification_channels.go

@@ -0,0 +1,225 @@
+package api
+
+// Push notification channels — self-hosted ntfy and Gotify endpoints users
+// attach to their account. insertUserNotification fans out best-effort.
+
+import (
+	"bytes"
+	"context"
+	"database/sql"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+
+	"containr/internal/database"
+	"containr/internal/database/sqlcdb"
+
+	"github.com/gin-gonic/gin"
+	"github.com/google/uuid"
+)
+
+// jarvis: ceiling — one shared client; no retry/backoff, delivery is
+// best-effort and failures are silent by design (notifications must never
+// break the producing flow).
+var pushHTTPClient = &http.Client{Timeout: 5 * time.Second}
+
+type notificationChannelDTO struct {
+	ID        string `json:"id"`
+	Kind      string `json:"kind"`
+	Endpoint  string `json:"endpoint"`
+	Enabled   bool   `json:"enabled"`
+	CreatedAt string `json:"created_at"`
+}
+
+func mapChannel(row sqlcdb.NotificationChannel) notificationChannelDTO {
+	return notificationChannelDTO{
+		ID:        row.ID.String(),
+		Kind:      row.Kind,
+		Endpoint:  row.Endpoint,
+		Enabled:   row.Enabled,
+		CreatedAt: row.CreatedAt.Time.Format(time.RFC3339),
+	}
+}
+
+func handleListNotificationChannels(c *gin.Context) {
+	userID, ok := requireAuthenticatedUserID(c)
+	if !ok {
+		return
+	}
+	db := c.MustGet("db").(*database.DB)
+	uid, _ := uuid.Parse(userID)
+	rows, err := sqlcdb.New(db.DB).ListAllNotificationChannelsByUser(c.Request.Context(), uid)
+	if err != nil {
+		respondError(c, http.StatusInternalServerError, "INTERNAL_ERROR", "Failed to list channels")
+		return
+	}
+	out := make([]notificationChannelDTO, 0, len(rows))
+	for _, r := range rows {
+		out = append(out, mapChannel(r))
+	}
+	c.JSON(http.StatusOK, gin.H{"channels": out})
+}
+
+func handleCreateNotificationChannel(c *gin.Context) {
+	userID, ok := requireAuthenticatedUserID(c)
+	if !ok {
+		return
+	}
+	var req struct {
+		Kind     string `json:"kind" binding:"required,oneof=ntfy gotify"`
+		Endpoint string `json:"endpoint" binding:"required"`
+		Token    string `json:"token"`
+	}
+	if err := c.ShouldBindJSON(&req); err != nil {
+		respondError(c, http.StatusBadRequest, "VALIDATION", "kind (ntfy|gotify) and endpoint are required")
+		return
+	}
+	endpoint := strings.TrimRight(strings.TrimSpace(req.Endpoint), "/")
+	u, err := url.Parse(endpoint)
+	if err != nil || u.Scheme == "" || u.Host == "" || (u.Scheme != "http" && u.Scheme != "https") {
+		respondError(c, http.StatusBadRequest, "VALIDATION", "endpoint must be a valid http(s) URL")
+		return
+	}
+	db := c.MustGet("db").(*database.DB)
+	uid, _ := uuid.Parse(userID)
+	row, err := sqlcdb.New(db.DB).InsertNotificationChannel(c.Request.Context(), sqlcdb.InsertNotificationChannelParams{
+		UserID:   uid,
+		Kind:     req.Kind,
+		Endpoint: endpoint,
+		Token:    sql.NullString{String: req.Token, Valid: req.Token != ""},
+	})
+	if err != nil {
+		respondError(c, http.StatusInternalServerError, "INTERNAL_ERROR", "Failed to create channel")
+		return
+	}
+	c.JSON(http.StatusCreated, gin.H{"channel": mapChannel(row)})
+}
+
+func handleDeleteNotificationChannel(c *gin.Context) {
+	userID, ok := requireAuthenticatedUserID(c)
+	if !ok {
+		return
+	}
+	id, err := uuid.Parse(c.Param("id"))
+	if err != nil {
+		respondError(c, http.StatusBadRequest, "VALIDATION", "Invalid channel id")
+		return
+	}
+	db := c.MustGet("db").(*database.DB)
+	uid, _ := uuid.Parse(userID)
+	n, err := sqlcdb.New(db.DB).DeleteNotificationChannel(c.Request.Context(), sqlcdb.DeleteNotificationChannelParams{
+		ID: id, UserID: uid,
+	})
+	if err != nil {
+		respondError(c, http.StatusInternalServerError, "INTERNAL_ERROR", "Failed to delete channel")
+		return
+	}
+	if n == 0 {
+		respondError(c, http.StatusNotFound, "NOT_FOUND", "Channel not found")
+		return
+	}
+	c.JSON(http.StatusOK, gin.H{"message": "Channel deleted"})
+}
+
+// handleTestNotificationChannel pushes a probe notification through the
+// channel — surfaces misconfiguration before real alerts depend on it.
+func handleTestNotificationChannel(c *gin.Context) {
+	userID, ok := requireAuthenticatedUserID(c)
+	if !ok {
+		return
+	}
+	id, err := uuid.Parse(c.Param("id"))
+	if err != nil {
+		respondError(c, http.StatusBadRequest, "VALIDATION", "Invalid channel id")
+		return
+	}
+	db := c.MustGet("db").(*database.DB)
+	uid, _ := uuid.Parse(userID)
+	rows, err := sqlcdb.New(db.DB).ListAllNotificationChannelsByUser(c.Request.Context(), uid)
+	if err != nil {
+		respondError(c, http.StatusInternalServerError, "INTERNAL_ERROR", "Failed to load channel")
+		return
+	}
+	var target *sqlcdb.NotificationChannel
+	for i := range rows {
+		if rows[i].ID == id {
+			target = &rows[i]
+			break
+		}
+	}
+	if target == nil {
+		respondError(c, http.StatusNotFound, "NOT_FOUND", "Channel not found")
+		return
+	}
+	if err := deliverPush(c.Request.Context(), *target, "test", "Containr test notification", "Your push channel is configured correctly."); err != nil {
+		respondError(c, http.StatusBadGateway, "DELIVERY_FAILED", fmt.Sprintf("Push failed: %v", err))
+		return
+	}
+	c.JSON(http.StatusOK, gin.H{"message": "Test notification sent"})
+}
+
+// deliverPush sends one notification through a channel. ntfy expects the
+// body at POST {endpoint} with Title/Priority headers; Gotify takes JSON at
+// POST {endpoint}/message?token=...
+func deliverPush(ctx context.Context, ch sqlcdb.NotificationChannel, kind, title, body string) error {
+	var req *http.Request
+	var err error
+	switch ch.Kind {
+	case "ntfy":
+		req, err = http.NewRequestWithContext(ctx, http.MethodPost, ch.Endpoint, strings.NewReader(body))
+		if err == nil {
+			req.Header.Set("Title", title)
+			req.Header.Set("Tags", "containr,"+kind)
+			if ch.Token.Valid && ch.Token.String != "" {
+				req.Header.Set("Authorization", "Bearer "+ch.Token.String)
+			}
+		}
+	case "gotify":
+		payload, _ := json.Marshal(map[string]interface{}{
+			"title":    title,
+			"message":  body,
+			"priority": 5,
+		})
+		endpoint := ch.Endpoint + "/message"
+		if ch.Token.Valid && ch.Token.String != "" {
+			endpoint += "?token=" + url.QueryEscape(ch.Token.String)
+		}
+		req, err = http.NewRequestWithContext(ctx, http.MethodPost, endpoint, bytes.NewReader(payload))
+		if err == nil {
+			req.Header.Set("Content-Type", "application/json")
+		}
+	default:
+		return fmt.Errorf("unsupported channel kind %q", ch.Kind)
+	}
+	if err != nil {
+		return err
+	}
+	res, err := pushHTTPClient.Do(req)
+	if err != nil {
+		return err
+	}
+	defer res.Body.Close()
+	if res.StatusCode >= 400 {
+		return fmt.Errorf("push endpoint returned %d", res.StatusCode)
+	}
+	return nil
+}
+
+// fanoutUserPush delivers a notification to every enabled channel the user
+// configured. Errors are swallowed — the in-app row already landed.
+func fanoutUserPush(db *database.DB, userID, kind, title, body string) {
+	uid, err := uuid.Parse(userID)
+	if err != nil {
+		return
+	}
+	rows, err := sqlcdb.New(db.DB).ListNotificationChannelsByUser(context.Background(), uid)
+	if err != nil || len(rows) == 0 {
+		return
+	}
+	for _, ch := range rows {
+		_ = deliverPush(context.Background(), ch, kind, title, body)
+	}
+}

app/backend/internal/api/notification_channels_test.go

@@ -0,0 +1,80 @@
+package api
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"containr/internal/database/sqlcdb"
+)
+
+func TestDeliverPushNtfy(t *testing.T) {
+	var gotAuth, gotTitle, gotTags, gotBody string
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		gotAuth = r.Header.Get("Authorization")
+		gotTitle = r.Header.Get("Title")
+		gotTags = r.Header.Get("Tags")
+		b, _ := io.ReadAll(r.Body)
+		gotBody = string(b)
+		w.WriteHeader(http.StatusOK)
+	}))
+	defer srv.Close()
+
+	ch := sqlcdb.NotificationChannel{
+		Kind:     "ntfy",
+		Endpoint: srv.URL + "/alerts",
+		Token:    sql.NullString{String: "tk_abc", Valid: true},
+	}
+	if err := deliverPush(context.Background(), ch, "deployment", "Deploy done", "svc is live"); err != nil {
+		t.Fatalf("deliverPush: %v", err)
+	}
+	if gotAuth != "Bearer tk_abc" {
+		t.Fatalf("auth header = %q", gotAuth)
+	}
+	if gotTitle != "Deploy done" || gotTags != "containr,deployment" || gotBody != "svc is live" {
+		t.Fatalf("title=%q tags=%q body=%q", gotTitle, gotTags, gotBody)
+	}
+}
+
+func TestDeliverPushGotify(t *testing.T) {
+	var gotPath, gotToken string
+	var payload map[string]interface{}
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		gotPath = r.URL.Path
+		gotToken = r.URL.Query().Get("token")
+		_ = json.NewDecoder(r.Body).Decode(&payload)
+		w.WriteHeader(http.StatusOK)
+	}))
+	defer srv.Close()
+
+	ch := sqlcdb.NotificationChannel{
+		Kind:     "gotify",
+		Endpoint: srv.URL,
+		Token:    sql.NullString{String: "apptoken", Valid: true},
+	}
+	if err := deliverPush(context.Background(), ch, "backup", "Backup done", "db backup ok"); err != nil {
+		t.Fatalf("deliverPush: %v", err)
+	}
+	if gotPath != "/message" || gotToken != "apptoken" {
+		t.Fatalf("path=%q token=%q", gotPath, gotToken)
+	}
+	if payload["title"] != "Backup done" || payload["message"] != "db backup ok" {
+		t.Fatalf("payload = %v", payload)
+	}
+}
+
+func TestDeliverPushFailure(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusInternalServerError)
+	}))
+	defer srv.Close()
+
+	ch := sqlcdb.NotificationChannel{Kind: "ntfy", Endpoint: srv.URL}
+	if err := deliverPush(context.Background(), ch, "k", "t", "b"); err == nil {
+		t.Fatal("expected error on 500")
+	}
+}

app/backend/internal/api/notifications.go

@@ -41,6 +41,7 @@ func insertUserNotification(db *database.DB, userID, kind, title, body, resource
 		ResourceID:   sql.NullString{String: resourceID, Valid: resourceID != ""},
 		CreatedAt:    sql.NullTime{Time: time.Now(), Valid: true},
 	})
+	go fanoutUserPush(db, userID, kind, title, body)
 }
 
 func mapNotification(row sqlcdb.Notification) NotificationItem {

app/backend/internal/api/routes.go

@@ -364,6 +364,10 @@ func SetupRoutes(router *gin.Engine, db *database.DB, redis *database.Redis, cfg
 			authed.GET("/notifications", handleListNotifications)
 			authed.POST("/notifications/:id/read", handleMarkNotificationRead)
 			authed.POST("/notifications/read-all", handleMarkAllNotificationsRead)
+			authed.GET("/notifications/channels", handleListNotificationChannels)
+			authed.POST("/notifications/channels", handleCreateNotificationChannel)
+			authed.POST("/notifications/channels/:id/test", handleTestNotificationChannel)
+			authed.DELETE("/notifications/channels/:id", handleDeleteNotificationChannel)
 
 			// WebSocket endpoint
 			authed.GET("/ws", handleWebSocket)