sdk/fidl/fuchsia.app/context.fidl

// Copyright 2019 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.app;

using fuchsia.io;

/// A common base protocol for fuchsia.app.(module|agent|*shell|).Context.
/// Clients of those protocols will have access to all of these methods through those interfaces.
[FragileBase]
protocol Context {
    /// Obtains a fuchsia.io.Directory of services from the agent specified in |request.handler|.
    /// Services are bound to |request.services|. The agent endpoint may close |request.services|
    /// at its discretion, at which point |request.controller| must be closed by the caller.
    ///
    /// If brokering a connection is successful, keeping |request.controller| open will ensure
    /// that the agent endpoint is not terminated.
    ///
    /// Failure to provide all required fields in |request| will close the
    /// Context channel with an ZX_ERR_INVALID_ARGS.
    ConnectToAgent(AgentConnectionRequest request);
};

table AgentConnectionRequest {
    /// The component URL of the agent which is to provide services.
    ///
    /// Required.
    1: ComponentUrl handler;

    /// |services| will be connected to a directory of services provided by |handler|.
    ///
    /// Required.
    2: request<fuchsia.io.Directory> services;

    /// The agent providing |services| stays alive so long as the channel backing |controller|
    /// is not dropped.
    ///
    /// Required.
    3: request<AgentController> controller;
};

/// This interface is used by calls to *Context/ConnectToAgent() to signal to the framework to keep
/// the agent alive, so long as the AgentController channel is open.
protocol AgentController {};