public/fidl/fuchsia.modular/intent/intent.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;

using fuchsia.mem;

// The Intent struct is a runtime descriptor for an abstract action to be initiated
// in Fuchsia. For details please see docs/intent.md.
struct Intent {
    // The name of the action represented by this Intent.
    //
    // This is nullable for backwards compatibility.
    // TODO(MI4-1100): Make action non-nullable.
    string? action;

    // An explicit handler for the Intent. Specified as the component URL of the
    // module.
    string? handler;

    // The parameters that will be passed to the handler of |action|.
    vector<IntentParameter>? parameters;
};

// A struct representing a parameter that is passed to the handler of an Intent's
// Action.
struct IntentParameter {
    // The name of the parameter. The handler (i.e. selected mod) will be provided
    // with the data for this parameter under a link called |name|.
    string? name;

    // The data that will be passed to the intent handler.
    IntentParameterData data;
};

union IntentParameterData {
    // Set this if you already have an Entity reference at runtime.
    // Entity.getTypes() will be used to set the constraints for this noun during
    // resolution.
    string entity_reference;

    // Set this if you have structured JSON data. Values typically are a JSON
    // object with a "@type" attribute and other associated data.  TODO(thatguy):
    // We need to decide if we want to keep this in place, or deprecate this
    // eventually and move entirely to using Entity references.
    //
    // DEPRECATED: Use |entity_reference|.
    fuchsia.mem.Buffer json;

    // Set this if you want to explicitly define this noun's allowed types. This
    // is also useful in the cases where the noun has a 'direction' of type
    // 'output', and you wish to set the allowable output types from the Module
    // (see docs/modular/manifests/action_template.md for a definition of
    // 'direction').
    //
    // Only one entry in |entity_type| must match the constraint specified by
    // the Module for the constraint to be considered satisfied.
    vector<string> entity_type;

    // Set this to use an existing Link accessible from your Module as the noun's
    // value.
    // TODO(thatguy): This is allowed to be null for backwards compatibility with
    // Mods that use the 'default link' (= a link with null name). Once no mods
    // use the default link any more, this can be made required again.
    // MI4-736
    string? link_name;

    // Set to re-use an existing link within a story.
    LinkPath link_path;
};