What causes "cannot select user in multiuser mode" in m1k1o/neko?

Do not call Select in multiuser mode; use the session/authenticated state instead of member lookup.

cannot select user in multiuser mode

Error message

cannot select user in multiuser mode

What it means

The multiuser provider does not keep an in-memory member registry keyed by ID; members exist only as config entries and sessions created on first login. Select() is therefore unsupported and always returns this error instead of a profile.

Source

Thrown at server/internal/member/multiuser/provider.go:73

	}

	return "", types.MemberProfile{}, types.ErrMemberInvalidPassword
}

func (provider *MemberProviderCtx) Insert(username string, password string, profile types.MemberProfile) (string, error) {
	return "", errors.New("new user is created on first login in multiuser mode")
}

func (provider *MemberProviderCtx) UpdateProfile(id string, profile types.MemberProfile) error {
	return nil
}

func (provider *MemberProviderCtx) UpdatePassword(id string, password string) error {
	return errors.New("password can only be modified in config while in multiuser mode")
}

func (provider *MemberProviderCtx) Select(id string) (types.MemberProfile, error) {
	return types.MemberProfile{}, errors.New("cannot select user in multiuser mode")
}

func (provider *MemberProviderCtx) SelectAll(limit int, offset int) (map[string]types.MemberProfile, error) {
	return map[string]types.MemberProfile{}, nil
}

func (provider *MemberProviderCtx) Delete(id string) error {
	return errors.New("cannot delete user in multiuser mode")
}

View on GitHub (pinned to b0f01cedea)

Solutions

Do not call Select in multiuser mode; use the session/authenticated state instead of member lookup.
Read the intended user data from the server config entries directly.
Switch to a dynamic member provider if per-ID profile lookup is required.

Example fix

// before
profile, err := memberClient.Select(id)

// after: guard against unsupported mode
if memberProvider == "multiuser" {
    return errors.New("user lookup unsupported in multiuser mode")
}
profile, err := memberClient.Select(id)

Defensive patterns

Strategy: validation

Validate before calling

if memberProvider == "multiuser" {
    return errors.New("per-ID member lookup unsupported in multiuser mode")
}
profile, err := memberClient.Select(id)

Type guard

func isSelectUnsupportedErr(err error) bool {
    return err != nil && strings.Contains(err.Error(), "cannot select user")
}

Try / catch

profile, err := memberClient.Select(id)
if err != nil {
    if isSelectUnsupportedErr(err) {
        profile = types.MemberProfile{} // fall back to empty/anonymous profile
    } else {
        return err
    }
}

Prevention

Avoid per-ID member lookups in static provider modes; use the session identity instead.
Derive profile data from config entries rather than the members API in multiuser mode.
Gate user-detail admin views on the active member provider.
Remember SelectAll returns an empty map in multiuser mode — do not infer users from it.

When it happens

Trigger: Any call to the member Select API (lookup a member profile by ID, e.g. admin user-detail endpoint) while the member provider is 'multiuser'.

Common situations: An admin panel tries to fetch a user profile by ID after authentication; in multiuser mode this lookup is not implemented, so it always fails even for users who logged in successfully.

Related errors

AI-assisted analysis of m1k1o/neko@b0f01cedea (2026-09-01). Data as JSON: /api/errors/ac34e27af47dd9a4. Report an issue: GitHub.