updates: add wrapper for API calls to update users

Signed-off-by: Sumner Evans <sumner.evans@automattic.com>

pkg/connector/api.go

@@ -0,0 +1,34 @@
+package connector
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/gotd/td/tg"
+)
+
+type hasUpdates interface {
+	GetUsers() []tg.UserClass
+}
+
+// Wrapper for API calls that return a response with updates.
+func APICallWithUpdates[U hasUpdates](ctx context.Context, t *TelegramClient, fn func() (U, error)) (U, error) {
+	resp, err := fn()
+	if err != nil {
+		return resp, err
+	}
+
+	// TODO do we also need to expand this to chats and messages?
+	for _, user := range resp.GetUsers() {
+		user, ok := user.(*tg.User)
+		if !ok {
+			return resp, fmt.Errorf("user is %T not *tg.User", user)
+		}
+		err := t.updateGhost(ctx, user.ID, user)
+		if err != nil {
+			return resp, err
+		}
+	}
+
+	return resp, nil
+}