Better example code for google protos (#542)

* Better example code for google protos

* Try fix windows build

* Try fix windows build

* Remove generated code in repo

examples/build.rs

@@ -6,5 +6,12 @@ fn main() {
 
     tonic_build::compile_protos("proto/helloworld/helloworld.proto").unwrap();
     tonic_build::compile_protos("proto/echo/echo.proto").unwrap();
-    tonic_build::compile_protos("proto/google/pubsub/pubsub.proto").unwrap();
+
+    tonic_build::configure()
+        .build_server(false)
+        .compile(
+            &["proto/googleapis/google/pubsub/v1/pubsub.proto"],
+            &["proto/googleapis"],
+        )
+        .unwrap();
 }

examples/proto/googleapis/google/api/annotations.proto

@@ -16,7 +16,7 @@ syntax = "proto3";
 
 package google.api;
 
-import "http.proto";
+import "google/api/http.proto";
 import "google/protobuf/descriptor.proto";
 
 option go_package = "google.golang.org/genproto/googleapis/api/annotations;annotations";

examples/proto/googleapis/google/api/client.proto

@@ -1,4 +1,4 @@
-// Copyright 2019 Google LLC.
+// Copyright 2020 Google LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -11,7 +11,6 @@
 // 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";
 

examples/proto/googleapis/google/api/field_behavior.proto

@@ -0,0 +1,84 @@
+// Copyright 2020 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 = "FieldBehaviorProto";
+option java_package = "com.google.api";
+option objc_class_prefix = "GAPI";
+
+extend google.protobuf.FieldOptions {
+  // A designation of a specific field behavior (required, output only, etc.)
+  // in protobuf messages.
+  //
+  // Examples:
+  //
+  //   string name = 1 [(google.api.field_behavior) = REQUIRED];
+  //   State state = 1 [(google.api.field_behavior) = OUTPUT_ONLY];
+  //   google.protobuf.Duration ttl = 1
+  //     [(google.api.field_behavior) = INPUT_ONLY];
+  //   google.protobuf.Timestamp expire_time = 1
+  //     [(google.api.field_behavior) = OUTPUT_ONLY,
+  //      (google.api.field_behavior) = IMMUTABLE];
+  repeated google.api.FieldBehavior field_behavior = 1052;
+}
+
+// An indicator of the behavior of a given field (for example, that a field
+// is required in requests, or given as output but ignored as input).
+// This **does not** change the behavior in protocol buffers itself; it only
+// denotes the behavior and may affect how API tooling handles the field.
+//
+// Note: This enum **may** receive new values in the future.
+enum FieldBehavior {
+  // Conventional default for enums. Do not use this.
+  FIELD_BEHAVIOR_UNSPECIFIED = 0;
+
+  // Specifically denotes a field as optional.
+  // While all fields in protocol buffers are optional, this may be specified
+  // for emphasis if appropriate.
+  OPTIONAL = 1;
+
+  // Denotes a field as required.
+  // This indicates that the field **must** be provided as part of the request,
+  // and failure to do so will cause an error (usually `INVALID_ARGUMENT`).
+  REQUIRED = 2;
+
+  // Denotes a field as output only.
+  // This indicates that the field is provided in responses, but including the
+  // field in a request does nothing (the server *must* ignore it and
+  // *must not* throw an error as a result of the field's presence).
+  OUTPUT_ONLY = 3;
+
+  // Denotes a field as input only.
+  // This indicates that the field is provided in requests, and the
+  // corresponding field is not included in output.
+  INPUT_ONLY = 4;
+
+  // Denotes a field as immutable.
+  // This indicates that the field may be set once in a request to create a
+  // resource, but may not be changed thereafter.
+  IMMUTABLE = 5;
+
+  // Denotes that a (repeated) field is an unordered list.
+  // This indicates that the service may provide the elements of the list
+  // in any arbitrary order, rather than the order the user originally
+  // provided. Additionally, the list's order may or may not be stable.
+  UNORDERED_LIST = 6;
+}

examples/proto/googleapis/google/api/http.proto

@@ -1,4 +1,4 @@
-// Copyright 2019 Google LLC.
+// Copyright 2020 Google LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -11,7 +11,6 @@
 // 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";
 

examples/proto/googleapis/google/api/resource.proto

@@ -0,0 +1,299 @@
+// Copyright 2020 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 cc_enable_arenas = true;
+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"
+//         name_descriptor: {
+//           pattern: "projects/{project}/topics/{topic}"
+//           parent_type: "cloudresourcemanager.googleapis.com/Project"
+//           parent_name_extractor: "projects/{project}"
+//         }
+//       };
+//     }
+//
+// The ResourceDescriptor Yaml config will look like:
+//
+//     resources:
+//     - type: "pubsub.googleapis.com/Topic"
+//       name_descriptor:
+//         - pattern: "projects/{project}/topics/{topic}"
+//           parent_type: "cloudresourcemanager.googleapis.com/Project"
+//           parent_name_extractor: "projects/{project}"
+//
+// 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"
+//         name_descriptor: {
+//           pattern: "projects/{project}/logs/{log}"
+//           parent_type: "cloudresourcemanager.googleapis.com/Project"
+//           parent_name_extractor: "projects/{project}"
+//         }
+//         name_descriptor: {
+//           pattern: "folders/{folder}/logs/{log}"
+//           parent_type: "cloudresourcemanager.googleapis.com/Folder"
+//           parent_name_extractor: "folders/{folder}"
+//         }
+//         name_descriptor: {
+//           pattern: "organizations/{organization}/logs/{log}"
+//           parent_type: "cloudresourcemanager.googleapis.com/Organization"
+//           parent_name_extractor: "organizations/{organization}"
+//         }
+//         name_descriptor: {
+//           pattern: "billingAccounts/{billing_account}/logs/{log}"
+//           parent_type: "billing.googleapis.com/BillingAccount"
+//           parent_name_extractor: "billingAccounts/{billing_account}"
+//         }
+//       };
+//     }
+//
+// The ResourceDescriptor Yaml config will look like:
+//
+//     resources:
+//     - type: 'logging.googleapis.com/LogEntry'
+//       name_descriptor:
+//         - pattern: "projects/{project}/logs/{log}"
+//           parent_type: "cloudresourcemanager.googleapis.com/Project"
+//           parent_name_extractor: "projects/{project}"
+//         - pattern: "folders/{folder}/logs/{log}"
+//           parent_type: "cloudresourcemanager.googleapis.com/Folder"
+//           parent_name_extractor: "folders/{folder}"
+//         - pattern: "organizations/{organization}/logs/{log}"
+//           parent_type: "cloudresourcemanager.googleapis.com/Organization"
+//           parent_name_extractor: "organizations/{organization}"
+//         - pattern: "billingAccounts/{billing_account}/logs/{log}"
+//           parent_type: "billing.googleapis.com/BillingAccount"
+//           parent_name_extractor: "billingAccounts/{billing_account}"
+//
+// For flexible resources, the resource name doesn't contain parent names, but
+// the resource itself has parents for policy evaluation.
+//
+// Example:
+//
+//     message Shelf {
+//       option (google.api.resource) = {
+//         type: "library.googleapis.com/Shelf"
+//         name_descriptor: {
+//           pattern: "shelves/{shelf}"
+//           parent_type: "cloudresourcemanager.googleapis.com/Project"
+//         }
+//         name_descriptor: {
+//           pattern: "shelves/{shelf}"
+//           parent_type: "cloudresourcemanager.googleapis.com/Folder"
+//         }
+//       };
+//     }
+//
+// The ResourceDescriptor Yaml config will look like:
+//
+//     resources:
+//     - type: 'library.googleapis.com/Shelf'
+//       name_descriptor:
+//         - pattern: "shelves/{shelf}"
+//           parent_type: "cloudresourcemanager.googleapis.com/Project"
+//         - pattern: "shelves/{shelf}"
+//           parent_type: "cloudresourcemanager.googleapis.com/Folder"
+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'. 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;
+}

examples/proto/googleapis/google/pubsub/v1/schema.proto

@@ -0,0 +1,289 @@
+// Copyright 2020 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.pubsub.v1;
+
+import "google/api/annotations.proto";
+import "google/api/client.proto";
+import "google/api/field_behavior.proto";
+import "google/api/resource.proto";
+import "google/protobuf/empty.proto";
+
+option cc_enable_arenas = true;
+option csharp_namespace = "Google.Cloud.PubSub.V1";
+option go_package = "google.golang.org/genproto/googleapis/pubsub/v1;pubsub";
+option java_multiple_files = true;
+option java_outer_classname = "SchemaProto";
+option java_package = "com.google.pubsub.v1";
+option php_namespace = "Google\\Cloud\\PubSub\\V1";
+option ruby_package = "Google::Cloud::PubSub::V1";
+
+// Service for doing schema-related operations.
+//
+// EXPERIMENTAL: The Schema service is in development and may not work yet.
+
+service SchemaService {
+  option (google.api.default_host) = "pubsub.googleapis.com";
+  option (google.api.oauth_scopes) =
+      "https://www.googleapis.com/auth/cloud-platform,"
+      "https://www.googleapis.com/auth/pubsub";
+
+  // Creates a schema.
+  rpc CreateSchema(CreateSchemaRequest) returns (Schema) {
+    option (google.api.http) = {
+      post: "/v1/{parent=projects/*}/schemas"
+      body: "schema"
+    };
+    option (google.api.method_signature) = "parent,schema,schema_id";
+  }
+
+  // Gets a schema.
+  rpc GetSchema(GetSchemaRequest) returns (Schema) {
+    option (google.api.http) = {
+      get: "/v1/{name=projects/*/schemas/*}"
+    };
+    option (google.api.method_signature) = "name";
+  }
+
+  // Lists schemas in a project.
+  rpc ListSchemas(ListSchemasRequest) returns (ListSchemasResponse) {
+    option (google.api.http) = {
+      get: "/v1/{parent=projects/*}/schemas"
+    };
+    option (google.api.method_signature) = "parent";
+  }
+
+  // Deletes a schema.
+  rpc DeleteSchema(DeleteSchemaRequest) returns (google.protobuf.Empty) {
+    option (google.api.http) = {
+      delete: "/v1/{name=projects/*/schemas/*}"
+    };
+    option (google.api.method_signature) = "name";
+  }
+
+  // Validates a schema.
+  rpc ValidateSchema(ValidateSchemaRequest) returns (ValidateSchemaResponse) {
+    option (google.api.http) = {
+      post: "/v1/{parent=projects/*}/schemas:validate"
+      body: "*"
+    };
+    option (google.api.method_signature) = "parent,schema";
+  }
+
+  // Validates a message against a schema.
+  rpc ValidateMessage(ValidateMessageRequest)
+      returns (ValidateMessageResponse) {
+    option (google.api.http) = {
+      post: "/v1/{parent=projects/*}/schemas:validateMessage"
+      body: "*"
+    };
+  }
+}
+
+// A schema resource.
+message Schema {
+  option (google.api.resource) = {
+    type: "pubsub.googleapis.com/Schema"
+    pattern: "projects/{project}/schemas/{schema}"
+  };
+
+  // Possible schema definition types.
+  enum Type {
+    // Default value. This value is unused.
+    TYPE_UNSPECIFIED = 0;
+
+    // A Protocol Buffer schema definition.
+    PROTOCOL_BUFFER = 1;
+
+    // An Avro schema definition.
+    AVRO = 2;
+  }
+
+  // Required. Name of the schema.
+  // Format is `projects/{project}/schemas/{schema}`.
+  string name = 1 [(google.api.field_behavior) = REQUIRED];
+
+  // The type of the schema definition.
+  Type type = 2;
+
+  // The definition of the schema. This should contain a string representing
+  // the full definition of the schema that is a valid schema definition of
+  // the type specified in `type`.
+  string definition = 3;
+}
+
+// Request for the CreateSchema method.
+message CreateSchemaRequest {
+  // Required. The name of the project in which to create the schema.
+  // Format is `projects/{project-id}`.
+  string parent = 1 [
+    (google.api.field_behavior) = REQUIRED,
+    (google.api.resource_reference) = {
+      child_type: "pubsub.googleapis.com/Schema"
+    }
+  ];
+
+  // Required. The schema object to create.
+  //
+  // This schema's `name` parameter is ignored. The schema object returned
+  // by CreateSchema will have a `name` made using the given `parent` and
+  // `schema_id`.
+  Schema schema = 2 [(google.api.field_behavior) = REQUIRED];
+
+  // The ID to use for the schema, which will become the final component of
+  // the schema's resource name.
+  //
+  // See https://cloud.google.com/pubsub/docs/admin#resource_names for resource
+  // name constraints.
+  string schema_id = 3;
+}
+
+// View of Schema object fields to be returned by GetSchema and ListSchemas.
+enum SchemaView {
+  // The default / unset value.
+  // The API will default to the BASIC view.
+  SCHEMA_VIEW_UNSPECIFIED = 0;
+
+  // Include the name and type of the schema, but not the definition.
+  BASIC = 1;
+
+  // Include all Schema object fields.
+  FULL = 2;
+}
+
+// Request for the GetSchema method.
+message GetSchemaRequest {
+  // Required. The name of the schema to get.
+  // Format is `projects/{project}/schemas/{schema}`.
+  string name = 1 [
+    (google.api.field_behavior) = REQUIRED,
+    (google.api.resource_reference) = { type: "pubsub.googleapis.com/Schema" }
+  ];
+
+  // The set of fields to return in the response. If not set, returns a Schema
+  // with `name` and `type`, but not `definition`. Set to `FULL` to retrieve all
+  // fields.
+  SchemaView view = 2;
+}
+
+// Request for the `ListSchemas` method.
+message ListSchemasRequest {
+  // Required. The name of the project in which to list schemas.
+  // Format is `projects/{project-id}`.
+  string parent = 1 [
+    (google.api.field_behavior) = REQUIRED,
+    (google.api.resource_reference) = {
+      type: "cloudresourcemanager.googleapis.com/Project"
+    }
+  ];
+
+  // The set of Schema fields to return in the response. If not set, returns
+  // Schemas with `name` and `type`, but not `definition`. Set to `FULL` to
+  // retrieve all fields.
+  SchemaView view = 2;
+
+  // Maximum number of schemas to return.
+  int32 page_size = 3;
+
+  // The value returned by the last `ListSchemasResponse`; indicates that
+  // this is a continuation of a prior `ListSchemas` call, and that the
+  // system should return the next page of data.
+  string page_token = 4;
+}
+
+// Response for the `ListSchemas` method.
+message ListSchemasResponse {
+  // The resulting schemas.
+  repeated Schema schemas = 1;
+
+  // If not empty, indicates that there may be more schemas that match the
+  // request; this value should be passed in a new `ListSchemasRequest`.
+  string next_page_token = 2;
+}
+
+// Request for the `DeleteSchema` method.
+message DeleteSchemaRequest {
+  // Required. Name of the schema to delete.
+  // Format is `projects/{project}/schemas/{schema}`.
+  string name = 1 [
+    (google.api.field_behavior) = REQUIRED,
+    (google.api.resource_reference) = { type: "pubsub.googleapis.com/Schema" }
+  ];
+}
+
+// Request for the `ValidateSchema` method.
+message ValidateSchemaRequest {
+  // Required. The name of the project in which to validate schemas.
+  // Format is `projects/{project-id}`.
+  string parent = 1 [
+    (google.api.field_behavior) = REQUIRED,
+    (google.api.resource_reference) = {
+      type: "cloudresourcemanager.googleapis.com/Project"
+    }
+  ];
+
+  // Required. The schema object to validate.
+  Schema schema = 2 [(google.api.field_behavior) = REQUIRED];
+}
+
+// Response for the `ValidateSchema` method.
+message ValidateSchemaResponse {}
+
+// Request for the `ValidateMessage` method.
+message ValidateMessageRequest {
+  // Required. The name of the project in which to validate schemas.
+  // Format is `projects/{project-id}`.
+  string parent = 1 [
+    (google.api.field_behavior) = REQUIRED,
+    (google.api.resource_reference) = {
+      type: "cloudresourcemanager.googleapis.com/Project"
+    }
+  ];
+
+  oneof schema_spec {
+    // Name of the schema against which to validate.
+    //
+    // Format is `projects/{project}/schemas/{schema}`.
+    string name = 2 [
+      (google.api.resource_reference) = { type: "pubsub.googleapis.com/Schema" }
+    ];
+
+    // Ad-hoc schema against which to validate
+    Schema schema = 3;
+  }
+
+  // Message to validate against the provided `schema_spec`.
+  bytes message = 4;
+
+  // The encoding expected for messages
+  Encoding encoding = 5;
+}
+
+// Response for the `ValidateMessage` method.
+message ValidateMessageResponse {}
+
+// Possible encoding types for messages.
+enum Encoding {
+  // Unspecified
+  ENCODING_UNSPECIFIED = 0;
+
+  // JSON encoding
+  JSON = 1;
+
+  // Binary encoding, as defined by the schema type. For some schema types,
+  // binary encoding may not be available.
+  BINARY = 2;
+}

tonic-build/README.md

@@ -21,6 +21,7 @@ tonic-build = <tonic-version>
 
 ### Simple
 
+In `build.rs`:
 ```rust
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     tonic_build::compile_protos("proto/service.proto")?;
@@ -41,3 +42,63 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
    Ok(())
 }
 ```
+See [more examples here](https://github.com/hyperium/tonic/tree/master/examples)
+
+### Google APIs example
+A good way to use Google API is probably using git submodules.
+
+So suppose in our `proto` folder we do:
+```
+git submodule add https://github.com/googleapis/googleapis
+```
+
+And a bunch of Google proto files in structure will be like this:
+```
+├── googleapis
+│   └── google
+│       ├── api
+│       │   ├── annotations.proto
+│       │   ├── client.proto
+│       │   ├── field_behavior.proto
+│       │   ├── http.proto
+│       │   └── resource.proto
+│       └── pubsub
+│           └── v1
+│               ├── pubsub.proto
+│               └── schema.proto
+```
+
+Then we can generate Rust code via this setup in our `build.rs`
+```rust
+fn main() {
+    tonic_build::configure()
+        .build_server(false)
+        //.out_dir("src/google")  // you can change the generated code's location
+        .compile(
+            &["proto/googleapis/google/pubsub/v1/pubsub.proto"],
+            &["proto/googleapis"], // specify the root location to search proto dependencies
+        ).unwrap();
+}
+```
+
+Then you can reference the generated Rust like this this in your code:
+```rust
+pub mod api {
+    tonic::include_proto!("google.pubsub.v1");
+}
+use api::{publisher_client::PublisherClient, ListTopicsRequest};
+```
+
+Or if you want to save the generated code in your own code base,
+you can uncomment the line `.out_dir(...)` above, and in your lib file
+config a mod like this:
+```rust
+pub mod google {
+    #[path = ""]
+    pub mod pubsub {
+        #[path = "google.pubsub.v1.rs"]
+        pub mod v1;
+    }
+}
+```
+See [the example here](https://github.com/hyperium/tonic/tree/master/examples/src/gcp)