initial commit

internal/httpapi/preferences.go

@@ -0,0 +1,75 @@
+package httpapi
+
+import (
+	"net/http"
+
+	"github.com/urpi/go-bananas/internal/domain"
+	"github.com/urpi/go-bananas/internal/store"
+)
+
+// PreferenceHandlers serves the caller's own interface preferences.
+//
+// A preference belongs to the account rather than to a browser, so it is stored
+// against the identity subject and travels with the person to another device. It
+// is deliberately not part of the session token: the token is issued by the
+// identity provider and this service does not control its claims, so a choice made
+// here has to be read back from this API.
+type PreferenceHandlers struct {
+	store *store.Store
+	log   Logger
+}
+
+// NewPreferenceHandlers builds the preference handler set.
+func NewPreferenceHandlers(st *store.Store, log Logger) *PreferenceHandlers {
+	return &PreferenceHandlers{store: st, log: log}
+}
+
+// Get returns the caller's preferences, or the empty preference when they have
+// chosen nothing yet.
+func (h *PreferenceHandlers) Get(w http.ResponseWriter, r *http.Request) {
+	identity := mustIdentity(r.Context())
+
+	prefs, err := h.store.Preferences(r.Context(), identity.Subject)
+	if err != nil {
+		h.log.Error("read preferences", "subject", identity.Subject, "error", err)
+		writeProblem(w, r, err)
+		return
+	}
+	writeJSON(w, r, http.StatusOK, prefs)
+}
+
+// Update records the caller's preferences and echoes back what was stored, so the
+// client renders the server's decision rather than its own input.
+//
+// An empty selectedTheme clears the choice. Clearing through the same endpoint
+// rather than a second route keeps the write surface to one path, which matters
+// because this endpoint is the only thing that writes the row.
+func (h *PreferenceHandlers) Update(w http.ResponseWriter, r *http.Request) {
+	identity := mustIdentity(r.Context())
+
+	var request domain.UserPreferences
+	if err := decodeJSON(r, &request); err != nil {
+		writeProblem(w, r, err)
+		return
+	}
+
+	stored, err := h.store.SetPreferences(r.Context(), identity.Subject, request)
+	if err != nil {
+		h.log.Warn("update preferences", "subject", identity.Subject, "error", err)
+		writeProblem(w, r, err)
+		return
+	}
+	writeJSON(w, r, http.StatusOK, stored)
+}
+
+// Reset forgets the caller's preferences and returns them to their defaults.
+func (h *PreferenceHandlers) Reset(w http.ResponseWriter, r *http.Request) {
+	identity := mustIdentity(r.Context())
+
+	if _, err := h.store.ClearPreferences(r.Context(), identity.Subject); err != nil {
+		h.log.Error("clear preferences", "subject", identity.Subject, "error", err)
+		writeProblem(w, r, err)
+		return
+	}
+	writeJSON(w, r, http.StatusOK, domain.UserPreferences{})
+}