socketio/socket.io · error · Error

No adapter for this namespace, are you trying to get the lis

Error message

No adapter for this namespace, are you trying to get the list of clients of a dynamic namespace?

What it means

Thrown by the deprecated BroadcastOperator.allSockets() when this.adapter is undefined (the BroadcastOperator was constructed without an adapter). allSockets() delegates to the namespace adapter; without one it cannot enumerate sockets. The message specifically flags dynamic namespaces, which do not have a concrete adapter instance to query.

Source

Thrown at packages/socket.io/lib/broadcast-operator.ts:349

          err.responses = responses;
          return reject(err);
        } else {
          return resolve(responses);
        }
      });
      this.emit(ev, ...(args as any[] as EventParams<EmitEvents, Ev>));
    });
  }

  /**
   * Gets a list of clients.
   *
   * @deprecated this method will be removed in the next major release, please use {@link Server#serverSideEmit} or
   * {@link fetchSockets} instead.
   */
  public allSockets(): Promise<Set<SocketId>> {
    if (!this.adapter) {
      throw new Error(
        "No adapter for this namespace, are you trying to get the list of clients of a dynamic namespace?",
      );
    }
    return this.adapter.sockets(this.rooms);
  }

  /**
   * Returns the matching socket instances. This method works across a cluster of several Socket.IO servers.
   *
   * Note: this method also works within a cluster of multiple Socket.IO servers, with a compatible {@link Adapter}.
   *
   * @example
   * // return all Socket instances
   * const sockets = await io.fetchSockets();
   *
   * // return all Socket instances in the "room1" room
   * const sockets = await io.in("room1").fetchSockets();
   *

View on GitHub (pinned to ae7fb46e08)

Solutions

1. Use a concrete namespace (io.of('/name')) instead of a dynamic regex namespace when you need to list sockets.
2. Migrate from the deprecated allSockets() to fetchSockets() on a concrete namespace.
3. For dynamic namespaces, iterate matched namespaces via io.of(/^/.../).sockets or resolve a specific namespace instance first.

Example fix

// before
const ids = await io.of(/^/tenant-/).allSockets(); // throws

// after
const ids = await io.of('/tenant-1').allSockets(); // concrete namespace
// or, the non-deprecated alternative:
const sockets = await io.of('/tenant-1').fetchSockets();

function hasAdapter(operator){ return !!operator.adapter; }

function isConcreteNamespace(ns){ return !!ns && !!ns.adapter; }

When it happens

Trigger: Calling allSockets() on a BroadcastOperator that has no adapter — typically obtained from a dynamic/regex namespace (io.of(/^/dynamic-/)) whose matching Namespace is abstract, or by constructing a BroadcastOperator directly without injecting an adapter.

Common situations: Using io.of(/regex/).allSockets() on a dynamic namespace; or calling the deprecated allSockets() (the message itself notes deprecation) instead of fetchSockets/allSockets on a concrete namespace.

Related errors

• "${String(ev)}" is a reserved event name
• "${String(ev)}" is a reserved event name
• You are trying to attach socket.io to an express request han

AI-assisted analysis of socketio/socket.io@ae7fb46e08 (2026-08-03). Data as JSON: /data/errors/7bfd7fa3a7a3a073.json. Report an issue: GitHub.