ScopedIdGenerator class

An IdGenerator that stamps a scope into every identifier it produces.

Entity ids have to be unique across a whole federation, not just within one store. A hub caches "which provider owns which id" and deduplicates aggregated listings by id; two nodes independently minting the same id would make one entity shadow the other, and route writes to the wrong machine. Independent processes cannot coordinate a counter, so the scope — normally the provider id — is what keeps them apart.

ScopedIdGenerator(RandomIdGenerator(), 'node-eu').next('rel');
// => 'rel-node-eu-1k3f9x'

The scope is also a diagnostic: an id in a log or a URL says which node created the record, which is the first thing you want to know when a federated deployment misbehaves.

Implemented types

• IdGenerator

Constructors

ScopedIdGenerator(IdGenerator inner, String scope)

Wraps inner, stamping scope into every id.

Properties

hashCode → int

The hash code for this object.

no setter, inherited

inner → IdGenerator

The generator supplying the unique part of each id.

final

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

scope → String

The scope stamped into every id, normalised to lower-case alphanumerics and -.

final

Methods

next([String prefix = '']) → String

Returns a fresh identifier, optionally namespaced with prefix (e.g. conn, node, req).

override

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