StableUserId class

Persists a stable opaque id per typed display name.

In real production, a chat app gets its userId from an external auth provider (Cognito sub, Firebase uid, etc.) — an opaque identifier distinct from the user's display name. Demo / example apps without that infrastructure still need stable ids so the backend can key conversations, history and contacts off the same row across logins.

forDisplayName mints a UUID v4 the first time it sees a name, persists it under <keyPrefix><name> in SharedPreferences, and returns the same id on subsequent calls. Useful as a drop-in for demo/example apps until they wire real auth.

final userId = await StableUserId.forDisplayName('alice');
final config = ChatConfig.withBasicAuth(
  username: userId,
  ...,
);

Properties

hashCode → int

The hash code for this object.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited

Static Methods

forDisplayName(String displayName, {SharedPreferences? prefs, String keyPrefix = defaultKeyPrefix}) → Future<String>

Returns the persisted UUID for displayName, minting a fresh one when none is stored yet. Whitespace in displayName is trimmed and the lookup is case-sensitive — pass the same canonical form (typically lowercased) you intend to use across sessions.

forget(String displayName, {SharedPreferences? prefs, String keyPrefix = defaultKeyPrefix}) → Future<void>

Removes the persisted id for displayName. The next call to forDisplayName with the same name will mint a fresh UUID. Useful as part of a "wipe demo data" flow.

Constants

defaultKeyPrefix → const String