Show notes from similar earlier incidents

Each incident gets a signature: the alert name plus the group labels that say what is broken, minus the ones that only say where it ran (instance, pod, container, ...). GET /api/incidents/{id}/similar returns resolved incidents in the same team with the same signature that have notes. Notes can be marked as the resolution note, "what fixed it", either with a resolution field on resolve or pinned on a note. Those lead the similar list, show on the incident page as "Seen before", and the triggered notification carries the latest one. Claude-Session: https://claude.ai/code/session_01MMados3BD1oSjevHxbmVqU
2026-09-25 15:42:25 +02:00
parent 734cd9c5fd
commit 60ebb75cd2
12 changed files with 400 additions and 23 deletions
@@ -0,0 +1,113 @@
+package api
+
+import (
+	"context"
+	"database/sql"
+	"net/http"
+	"strconv"
+	"time"
+
+	"git.ryuvia.com/niklas/terdut-server/internal/models"
+)
+
+const (
+	similarDefaultLimit = 5
+	similarMaxLimit     = 20
+)
+
+// handleIncidentSimilar lists earlier, resolved incidents in the same team with
+// the same signature that someone left notes on, incidents with a resolution
+// note first. This is the "have we seen this before" answer for a responder
+// looking at a fresh incident; the plain notes are one timeline fetch away.
+func handleIncidentSimilar(db *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		id, ok := incidentIDParam(w, r, db)
+		if !ok {
+			return
+		}
+		limit := similarDefaultLimit
+		if v := r.URL.Query().Get("limit"); v != "" {
+			n, err := strconv.Atoi(v)
+			if err != nil || n < 1 {
+				respond(w, http.StatusBadRequest, errResp("invalid limit"))
+				return
+			}
+			limit = min(n, similarMaxLimit)
+		}
+
+		out, err := similarIncidents(r.Context(), db, id, limit)
+		if err != nil {
+			respond(w, http.StatusInternalServerError, errResp("internal error"))
+			return
+		}
+		respond(w, http.StatusOK, out)
+	}
+}
+
+func similarIncidents(ctx context.Context, q querier, id int64, limit int) ([]models.SimilarIncident, error) {
+	rows, err := q.QueryContext(ctx, `
+		SELECT o.id, o.title, o.triggered_at, o.resolved_at,
+		       (SELECT COUNT(*) FROM incident_events e
+		         WHERE e.incident_id = o.id AND e.type = $3)
+		FROM   incidents i
+		JOIN   incidents o ON o.team_id = i.team_id AND o.signature = i.signature
+		WHERE  i.id = $1 AND o.id <> i.id AND o.resolved_at IS NOT NULL
+		  AND  EXISTS (SELECT 1 FROM incident_events e
+		                WHERE e.incident_id = o.id AND e.type IN ($3, $4))
+		ORDER  BY EXISTS (SELECT 1 FROM incident_events e
+		                   WHERE e.incident_id = o.id AND e.type = $4) DESC,
+		          o.triggered_at DESC
+		LIMIT  $2`, id, limit, evNote, evResolutionNote)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	out := []models.SimilarIncident{}
+	ids := []int64{}
+	for rows.Next() {
+		var s models.SimilarIncident
+		var triggered, resolved int64
+		if err := rows.Scan(&s.ID, &s.Title, &triggered, &resolved, &s.NoteCount); err != nil {
+			return nil, err
+		}
+		s.TriggeredAt = time.Unix(triggered, 0).UTC()
+		s.ResolvedAt = time.Unix(resolved, 0).UTC()
+		s.ResolutionNotes = []models.IncidentEvent{}
+		out = append(out, s)
+		ids = append(ids, s.ID)
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+	if len(out) == 0 {
+		return out, nil
+	}
+
+	nrows, err := q.QueryContext(ctx, `
+		SELECT e.id, e.incident_id, e.type, e.user_id, u.username, e.detail, e.created_at
+		FROM   incident_events e
+		LEFT   JOIN users u ON u.id = e.user_id
+		WHERE  e.incident_id = ANY($1) AND e.type = $2
+		ORDER  BY e.created_at, e.id`, ids, evResolutionNote)
+	if err != nil {
+		return nil, err
+	}
+	defer nrows.Close()
+
+	byID := make(map[int64]*models.SimilarIncident, len(out))
+	for i := range out {
+		byID[out[i].ID] = &out[i]
+	}
+	for nrows.Next() {
+		var e models.IncidentEvent
+		var ts int64
+		if err := nrows.Scan(&e.ID, &e.IncidentID, &e.Type, &e.UserID, &e.Username, &e.Detail, &ts); err != nil {
+			return nil, err
+		}
+		e.CreatedAt = time.Unix(ts, 0).UTC()
+		s := byID[e.IncidentID]
+		s.ResolutionNotes = append(s.ResolutionNotes, e)
+	}
+	return out, nrows.Err()
+}