Publish ITWorx Pulse source

internal/inventoryapi/handler.go

@@ -0,0 +1,142 @@
+package inventoryapi
+
+import (
+	"context"
+	"encoding/base64"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"github.com/itworx/pulse/internal/auth"
+	"github.com/itworx/pulse/internal/inventory"
+	"github.com/itworx/pulse/internal/problem"
+)
+
+type Repository interface {
+	SearchEntities(context.Context, inventory.EntityFilter) ([]inventory.EntitySummary, error)
+	GetEntityDetail(context.Context, string) (inventory.EntityDetail, error)
+}
+
+type Handler struct{ Repository Repository }
+
+func (h Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	if h.Repository == nil {
+		fail(w, r, http.StatusServiceUnavailable, "INVENTORY_UNAVAILABLE", "Inventory is not configured.")
+		return
+	}
+	if _, ok := auth.PrincipalFromContext(r.Context()); !ok {
+		fail(w, r, http.StatusUnauthorized, "UNAUTHORIZED", "Authentication is required to read inventory.")
+		return
+	}
+	if r.Method != http.MethodGet {
+		fail(w, r, http.StatusMethodNotAllowed, "METHOD_NOT_ALLOWED", "Only read-only inventory operations are supported.")
+		return
+	}
+	path := strings.Trim(strings.TrimPrefix(r.URL.Path, "/api/v1/entities"), "/")
+	if path == "" {
+		h.list(w, r)
+		return
+	}
+	parts := strings.Split(path, "/")
+	if len(parts) == 1 && parts[0] != "" {
+		h.detail(w, r, parts[0], false)
+		return
+	}
+	if len(parts) == 2 && parts[0] != "" && parts[1] == "relations" {
+		h.detail(w, r, parts[0], true)
+		return
+	}
+	fail(w, r, http.StatusNotFound, "NOT_FOUND", "Inventory route not found.")
+}
+
+func (h Handler) list(w http.ResponseWriter, r *http.Request) {
+	limit := 50
+	if raw := r.URL.Query().Get("limit"); raw != "" {
+		value, err := strconv.Atoi(raw)
+		if err != nil || value < 1 || value > 100 {
+			fail(w, r, http.StatusBadRequest, "INVALID_LIMIT", "The inventory limit must be between 1 and 100.")
+			return
+		}
+		limit = value
+	}
+	afterName, afterID, err := decodeCursor(r.URL.Query().Get("after"))
+	if err != nil {
+		fail(w, r, http.StatusBadRequest, "INVALID_CURSOR", "The inventory cursor is invalid.")
+		return
+	}
+	direction := r.URL.Query().Get("order")
+	if direction == "" {
+		direction = "asc"
+	}
+	if direction != "asc" && direction != "desc" {
+		fail(w, r, http.StatusBadRequest, "INVALID_SORT", "Inventory order must be asc or desc.")
+		return
+	}
+	filter := inventory.EntityFilter{Limit: limit, AfterName: afterName, AfterID: afterID, Search: strings.TrimSpace(r.URL.Query().Get("q")), EntityType: strings.TrimSpace(r.URL.Query().Get("type")), Status: strings.TrimSpace(r.URL.Query().Get("status")), Direction: direction}
+	items, err := h.Repository.SearchEntities(r.Context(), filter)
+	if err != nil {
+		repositoryFailure(w, r, err)
+		return
+	}
+	hasMore := len(items) > limit
+	if hasMore {
+		items = items[:limit]
+	}
+	next := ""
+	if hasMore && len(items) > 0 {
+		last := items[len(items)-1]
+		next = encodeCursor(last.DisplayName, last.ID)
+	}
+	writeJSON(w, map[string]any{"items": items, "nextCursor": next, "hasMore": hasMore, "filters": map[string]string{"q": filter.Search, "type": filter.EntityType, "status": filter.Status, "order": filter.Direction}})
+}
+
+func (h Handler) detail(w http.ResponseWriter, r *http.Request, id string, relationsOnly bool) {
+	detail, err := h.Repository.GetEntityDetail(r.Context(), id)
+	if err != nil {
+		if errors.Is(err, inventory.ErrNotFound) {
+			fail(w, r, http.StatusNotFound, "ENTITY_NOT_FOUND", "The inventory entity does not exist.")
+			return
+		}
+		repositoryFailure(w, r, err)
+		return
+	}
+	if relationsOnly {
+		writeJSON(w, map[string]any{"items": detail.Relations})
+		return
+	}
+	writeJSON(w, detail)
+}
+
+func encodeCursor(name, id string) string {
+	return base64.RawURLEncoding.EncodeToString([]byte(strings.ToLower(name) + "\x00" + id))
+}
+func decodeCursor(value string) (string, string, error) {
+	if value == "" {
+		return "", "", nil
+	}
+	decoded, err := base64.RawURLEncoding.DecodeString(value)
+	if err != nil {
+		return "", "", err
+	}
+	parts := strings.Split(string(decoded), "\x00")
+	if len(parts) != 2 || parts[0] == "" || parts[1] == "" {
+		return "", "", strconv.ErrSyntax
+	}
+	return parts[0], parts[1], nil
+}
+func repositoryFailure(w http.ResponseWriter, r *http.Request, err error) {
+	if errors.Is(err, context.Canceled) || errors.Is(err, context.DeadlineExceeded) {
+		return
+	}
+	fail(w, r, http.StatusServiceUnavailable, "INVENTORY_UNAVAILABLE", "Inventory could not be read safely.")
+}
+func fail(w http.ResponseWriter, r *http.Request, status int, code, detail string) {
+	problem.Write(w, r, status, code, http.StatusText(status), detail, nil)
+}
+func writeJSON(w http.ResponseWriter, value any) {
+	w.Header().Set("Content-Type", "application/json")
+	w.Header().Set("Cache-Control", "private, no-store")
+	_ = json.NewEncoder(w).Encode(value)
+}