sdk/fidl/fuchsia.component.internal/component_id_index.fidl

// Copyright 2020 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.

/// The FIDL representation of the component ID Index.
///
/// See (component ID index)[//docs/development/components/component_id_index.md]
/// for documentation on the schema.
library fuchsia.component.internal;

using fuchsia.component;
using fuchsia.sys;

/// 256 bits encoded in lower-cased base64 (64 chars).
alias InstanceId = string:64;
/// The path to the appmgr realm where the component runs.
alias AppmgrRealmPath = vector<fuchsia.component.name>:256;

/// Top-level type describing the component ID index.
table ComponentIdIndex {
    /// If `true`, `appmgr` requires components which use
    /// `isolated-persistent-storage` to list their instance in the index.
    /// Otherwise, they fail to run.  Note that this flag is only used by appmgr,
    /// and is ignored by component_manager.
    1: bool appmgr_restrict_isolated_persistent_storage;

    /// A list of component ID instance entries.
    ///
    /// Required, but may be empty.
    2: vector<InstanceIdEntry>:1024 instances;
};

table InstanceIdEntry {
    /// A 256-bit identifier encoded in base64 which is unique across all other
    /// instance IDs in the index.
    1: InstanceId instance_id;

    /// An appmgr-based moniker identifying an appmgr component instance
    /// associated with `instance_id`. Note that component manager ignores
    /// this field; it is only consumed by appmgr.
    2: AppmgrMoniker appmgr_moniker;

    /// The absolute moniker identifying the component instance. Note that
    /// appmgr ignores thie field; it is only consumed by component manager.
    3: string:fuchsia.component.MAX_MONIKER_LENGTH moniker;
};

table AppmgrMoniker {
    /// The component's URL.
    1: fuchsia.sys.component_url url;

    /// The path to the appmgr realm where the component runs.
    2: AppmgrRealmPath realm_path;

    /// The component instance's previous realm paths. `appmgr` will consider
    /// these realms in addition to `realm_path`. This feature is useful when
    /// moving a component to a new `realm_path`, but still needing to retain the
    /// previous realm paths. For example, this feature can be used when a
    /// component ID index change and the realm path code change cannot be
    /// submitted atomically.
    ///
    /// Optional.
    3: vector<AppmgrRealmPath>:64 transitional_realm_paths;
};