sdk/fidl/fuchsia.modular/entity/entity_reference_factory.fidl

// Copyright 2017 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

library fuchsia.modular;

/// Agents use this interface to create Entity references that can subsequently
/// be dereferenced into an `Entity` interface using `EntityResolver`.
/// Agents that create entity references must also expose an `EntityProvider`
/// service in their application's outgoing services, so that agents can provide
/// data for `Entity`s that they create. This interface is available through an
/// agent's `AgentContext`.
protocol EntityReferenceFactory {
    /// Agents call this to manufacture a reference for an Entity they will
    /// provide. Returns an opaque, persistable `entity_reference` that components
    /// can resolve into an `Entity` interface using `EntityResolver`. When data is
    /// requested from an `Entity` interface resolved from this `entity_reference`,
    /// the `cookie` associated with this `entity_reference` will be passed back to
    /// the `EntityProvider` of the Agent that originally created this reference.
    ///
    /// `cookie` should uniquely identify the `Entity` within the scope of the
    /// calling entity provider. For example, it may be used as the primary key
    /// value for a database.
    CreateReference(string cookie) -> (string entity_reference);
};