// Copyright 2026 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

syntax = "proto3";

package google.api;

import "google/protobuf/descriptor.proto";

option go_package = "google.golang.org/genproto/googleapis/api/annotations;annotations";
option java_multiple_files = true;
option java_outer_classname = "ResourceProto";
option java_package = "com.google.api";
option objc_class_prefix = "GAPI";

extend google.protobuf.FieldOptions {
  // An annotation that describes a resource reference, see
  // [ResourceReference][].
  google.api.ResourceReference resource_reference = 1055;
}

extend google.protobuf.FileOptions {
  // An annotation that describes a resource definition without a corresponding
  // message; see [ResourceDescriptor][].
  repeated google.api.ResourceDescriptor resource_definition = 1053;
}

extend google.protobuf.MessageOptions {
  // An annotation that describes a resource definition, see
  // [ResourceDescriptor][].
  google.api.ResourceDescriptor resource = 1053;
}

// A simple descriptor of a resource type.
//
// ResourceDescriptor annotates a resource message (either by means of a
// protobuf annotation or use in the service config), and associates the
// resource's schema, the resource type, and the pattern of the resource name.
//
// Example:
//
//     message Topic {
//       // Indicates this message defines a resource schema.
//       // Declares the resource type in the format of {service}/{kind}.
//       // For Kubernetes resources, the format is {api group}/{kind}.
//       option (google.api.resource) = {
//         type: "pubsub.googleapis.com/Topic"
//         pattern: "projects/{project}/topics/{topic}"
//       };
//     }
//
// The ResourceDescriptor Yaml config will look like:
//
//     resources:
//     - type: "pubsub.googleapis.com/Topic"
//       pattern: "projects/{project}/topics/{topic}"
//
// Sometimes, resources have multiple patterns, typically because they can
// live under multiple parents.
//
// Example:
//
//     message LogEntry {
//       option (google.api.resource) = {
//         type: "logging.googleapis.com/LogEntry"
//         pattern: "projects/{project}/logs/{log}"
//         pattern: "folders/{folder}/logs/{log}"
//         pattern: "organizations/{organization}/logs/{log}"
//         pattern: "billingAccounts/{billing_account}/logs/{log}"
//       };
//     }
//
// The ResourceDescriptor Yaml config will look like:
//
//     resources:
//     - type: 'logging.googleapis.com/LogEntry'
//       pattern: "projects/{project}/logs/{log}"
//       pattern: "folders/{folder}/logs/{log}"
//       pattern: "organizations/{organization}/logs/{log}"
//       pattern: "billingAccounts/{billing_account}/logs/{log}"
message ResourceDescriptor {
  // A description of the historical or future-looking state of the
  // resource pattern.
  enum History {
    // The "unset" value.
    HISTORY_UNSPECIFIED = 0;

    // The resource originally had one pattern and launched as such, and
    // additional patterns were added later.
    ORIGINALLY_SINGLE_PATTERN = 1;

    // The resource has one pattern, but the API owner expects to add more
    // later. (This is the inverse of ORIGINALLY_SINGLE_PATTERN, and prevents
    // that from being necessary once there are multiple patterns.)
    FUTURE_MULTI_PATTERN = 2;
  }

  // A flag representing a specific style that a resource claims to conform to.
  enum Style {
    // The unspecified value. Do not use.
    STYLE_UNSPECIFIED = 0;

    // This resource is intended to be "declarative-friendly".
    //
    // Declarative-friendly resources must be more strictly consistent, and
    // setting this to true communicates to tools that this resource should
    // adhere to declarative-friendly expectations.
    //
    // Note: This is used by the API linter (linter.aip.dev) to enable
    // additional checks.
    DECLARATIVE_FRIENDLY = 1;
  }

  // The resource type. It must be in the format of
  // {service_name}/{resource_type_kind}. The `resource_type_kind` must be
  // singular and must not include version numbers.
  //
  // Example: `storage.googleapis.com/Bucket`
  //
  // The value of the resource_type_kind must follow the regular expression
  // /[A-Za-z][a-zA-Z0-9]+/. It should start with an upper case character and
  // should use PascalCase (UpperCamelCase). The maximum number of
  // characters allowed for the `resource_type_kind` is 100.
  string type = 1;

  // Optional. The relative resource name pattern associated with this resource
  // type. The DNS prefix of the full resource name shouldn't be specified here.
  //
  // The path pattern must follow the syntax, which aligns with HTTP binding
  // syntax:
  //
  //     Template = Segment { "/" Segment } ;
  //     Segment = LITERAL | Variable ;
  //     Variable = "{" LITERAL "}" ;
  //
  // Examples:
  //
  //     - "projects/{project}/topics/{topic}"
  //     - "projects/{project}/knowledgeBases/{knowledge_base}"
  //
  // The components in braces correspond to the IDs for each resource in the
  // hierarchy. It is expected that, if multiple patterns are provided,
  // the same component name (e.g. "project") refers to IDs of the same
  // type of resource.
  repeated string pattern = 2;

  // Optional. The field on the resource that designates the resource name
  // field. If omitted, this is assumed to be "name".
  string name_field = 3;

  // Optional. The historical or future-looking state of the resource pattern.
  //
  // Example:
  //
  //     // The InspectTemplate message originally only supported resource
  //     // names with organization, and project was added later.
  //     message InspectTemplate {
  //       option (google.api.resource) = {
  //         type: "dlp.googleapis.com/InspectTemplate"
  //         pattern:
  //         "organizations/{organization}/inspectTemplates/{inspect_template}"
  //         pattern: "projects/{project}/inspectTemplates/{inspect_template}"
  //         history: ORIGINALLY_SINGLE_PATTERN
  //       };
  //     }
  History history = 4;

  // The plural name used in the resource name and permission names, such as
  // 'projects' for the resource name of 'projects/{project}' and the permission
  // name of 'cloudresourcemanager.googleapis.com/projects.get'. One exception
  // to this is for Nested Collections that have stuttering names, as defined
  // in [AIP-122](https://google.aip.dev/122#nested-collections), where the
  // collection ID in the resource name pattern does not necessarily directly
  // match the `plural` value.
  //
  // It is the same concept of the `plural` field in k8s CRD spec
  // https://kubernetes.io/docs/tasks/access-kubernetes-api/custom-resources/custom-resource-definitions/
  //
  // Note: The plural form is required even for singleton resources. See
  // https://aip.dev/156
  string plural = 5;

  // The same concept of the `singular` field in k8s CRD spec
  // https://kubernetes.io/docs/tasks/access-kubernetes-api/custom-resources/custom-resource-definitions/
  // Such as "project" for the `resourcemanager.googleapis.com/Project` type.
  string singular = 6;

  // Style flag(s) for this resource.
  // These indicate that a resource is expected to conform to a given
  // style. See the specific style flags for additional information.
  repeated Style style = 10;
}

// Defines a proto annotation that describes a string field that refers to
// an API resource.
message ResourceReference {
  // The resource type that the annotated field references.
  //
  // Example:
  //
  //     message Subscription {
  //       string topic = 2 [(google.api.resource_reference) = {
  //         type: "pubsub.googleapis.com/Topic"
  //       }];
  //     }
  //
  // Occasionally, a field may reference an arbitrary resource. In this case,
  // APIs use the special value * in their resource reference.
  //
  // Example:
  //
  //     message GetIamPolicyRequest {
  //       string resource = 2 [(google.api.resource_reference) = {
  //         type: "*"
  //       }];
  //     }
  string type = 1;

  // The resource type of a child collection that the annotated field
  // references. This is useful for annotating the `parent` field that
  // doesn't have a fixed resource type.
  //
  // Example:
  //
  //     message ListLogEntriesRequest {
  //       string parent = 1 [(google.api.resource_reference) = {
  //         child_type: "logging.googleapis.com/LogEntry"
  //       };
  //     }
  string child_type = 2;
}
