// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc.
// http://code.google.com/p/protobuf/
//
// 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.
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using Google.ProtocolBuffers.DescriptorProtos;
namespace Google.ProtocolBuffers.Descriptors {
/// <summary>
/// Describes a .proto file, including everything defined within.
/// IDescriptor is implemented such that the File property returns this descriptor,
/// and the FullName is the same as the Name.
/// </summary>
public sealed class FileDescriptor : IDescriptor<FileDescriptorProto> {
private readonly FileDescriptorProto proto;
private readonly IList<MessageDescriptor> messageTypes;
private readonly IList<EnumDescriptor> enumTypes;
private readonly IList<ServiceDescriptor> services;
private readonly IList<FieldDescriptor> extensions;
private readonly IList<FileDescriptor> dependencies;
private readonly DescriptorPool pool;
private FileDescriptor(FileDescriptorProto proto, FileDescriptor[] dependencies, DescriptorPool pool) {
this.pool = pool;
this.proto = proto;
this.dependencies = new ReadOnlyCollection<FileDescriptor>((FileDescriptor[]) dependencies.Clone());
pool.AddPackage(Package, this);
messageTypes = DescriptorUtil.ConvertAndMakeReadOnly(proto.MessageTypeList,
(message, index) => new MessageDescriptor(message, this, null, index));
enumTypes = DescriptorUtil.ConvertAndMakeReadOnly(proto.EnumTypeList,
(enumType, index) => new EnumDescriptor(enumType, this, null, index));
services = DescriptorUtil.ConvertAndMakeReadOnly(proto.ServiceList,
(service, index) => new ServiceDescriptor(service, this, index));
extensions = DescriptorUtil.ConvertAndMakeReadOnly(proto.ExtensionList,
(field, index) => new FieldDescriptor(field, this, null, index, true));
}
/// <value>
/// The descriptor in its protocol message representation.
/// </value>
public FileDescriptorProto Proto {
get { return proto; }
}
/// <value>
/// The <see cref="FileOptions" /> defined in <c>descriptor.proto</c>.
/// </value>
public FileOptions Options {
get { return proto.Options; }
}
/// <value>
/// The file name.
/// </value>
public string Name {
get { return proto.Name; }
}
/// <summary>
/// The package as declared in the .proto file. This may or may not
/// be equivalent to the .NET namespace of the generated classes.
/// </summary>
public string Package {
get { return proto.Package; }
}
/// <value>
/// Unmodifiable list of top-level message types declared in this file.
/// </value>
public IList<MessageDescriptor> MessageTypes {
get { return messageTypes; }
}
/// <value>
/// Unmodifiable list of top-level enum types declared in this file.
/// </value>
public IList<EnumDescriptor> EnumTypes {
get { return enumTypes; }
}
/// <value>
/// Unmodifiable list of top-level services declared in this file.
/// </value>
public IList<ServiceDescriptor> Services {
get { return services; }
}
/// <value>
/// Unmodifiable list of top-level extensions declared in this file.
/// </value>
public IList<FieldDescriptor> Extensions {
get { return extensions; }
}
/// <value>
/// Unmodifiable list of this file's dependencies (imports).
/// </value>
public IList<FileDescriptor> Dependencies {
get { return dependencies; }
}
/// <value>
/// Implementation of IDescriptor.FullName - just returns the same as Name.
/// </value>
string IDescriptor.FullName {
get { return Name; }
}
/// <value>
/// Implementation of IDescriptor.File - just returns this descriptor.
/// </value>
FileDescriptor IDescriptor.File {
get { return this; }
}
/// <value>
/// Protocol buffer describing this descriptor.
/// </value>
IMessage IDescriptor.Proto {
get { return Proto; }
}
/// <value>
/// Pool containing symbol descriptors.
/// </value>
internal DescriptorPool DescriptorPool {
get { return pool; }
}
/// <summary>
/// Finds a type (message, enum, service or extension) in the file by name. Does not find nested types.
/// </summary>
/// <param name="name">The unqualified type name to look for.</param>
/// <typeparam name="T">The type of descriptor to look for (or ITypeDescriptor for any)</typeparam>
/// <returns>The type's descriptor, or null if not found.</returns>
public T FindTypeByName<T>(String name)
where T : class, IDescriptor {
// Don't allow looking up nested types. This will make optimization
// easier later.
if (name.IndexOf('.') != -1) {
return null;
}
if (Package.Length > 0) {
name = Package + "." + name;
}
T result = pool.FindSymbol<T>(name);
if (result != null && result.File == this) {
return result;
}
return null;
}
/// <summary>
/// Builds a FileDescriptor from its protocol buffer representation.
/// </summary>
/// <param name="proto">The protocol message form of the FileDescriptor.</param>
/// <param name="dependencies">FileDescriptors corresponding to all of the
/// file's dependencies, in the exact order listed in the .proto file. May be null,
/// in which case it is treated as an empty array.</param>
/// <exception cref="DescriptorValidationException">If <paramref name="proto"/> is not
/// a valid descriptor. This can occur for a number of reasons, such as a field
/// having an undefined type or because two messages were defined with the same name.</exception>
public static FileDescriptor BuildFrom(FileDescriptorProto proto, FileDescriptor[] dependencies) {
// Building descriptors involves two steps: translating and linking.
// In the translation step (implemented by FileDescriptor's
// constructor), we build an object tree mirroring the
// FileDescriptorProto's tree and put all of the descriptors into the
// DescriptorPool's lookup tables. In the linking step, we look up all
// type references in the DescriptorPool, so that, for example, a
// FieldDescriptor for an embedded message contains a pointer directly
// to the Descriptor for that message's type. We also detect undefined
// types in the linking step.
if (dependencies == null) {
dependencies = new FileDescriptor[0];
}
DescriptorPool pool = new DescriptorPool(dependencies);
FileDescriptor result = new FileDescriptor(proto, dependencies, pool);
if (dependencies.Length != proto.DependencyCount) {
throw new DescriptorValidationException(result,
"Dependencies passed to FileDescriptor.BuildFrom() don't match " +
"those listed in the FileDescriptorProto.");
}
for (int i = 0; i < proto.DependencyCount; i++) {
if (dependencies[i].Name != proto.DependencyList[i]) {
/*throw new DescriptorValidationException(result,
"Dependencies passed to FileDescriptor.BuildFrom() don't match " +
"those listed in the FileDescriptorProto.");*/
}
}
result.CrossLink();
return result;
}
private void CrossLink() {
foreach (MessageDescriptor message in messageTypes) {
message.CrossLink();
}
foreach (ServiceDescriptor service in services) {
service.CrossLink();
}
foreach (FieldDescriptor extension in extensions) {
extension.CrossLink();
}
foreach (MessageDescriptor message in messageTypes) {
message.CheckRequiredFields();
}
}
/// <summary>
/// This method is to be called by generated code only. It is equivalent
/// to BuilderFrom except that the FileDescriptorProto is encoded in
/// protocol buffer wire format.
/// </summary>
public static FileDescriptor InternalBuildGeneratedFileFrom(byte[] descriptorData,
FileDescriptor[] dependencies) {
FileDescriptorProto proto = FileDescriptorProto.ParseFrom(descriptorData);
return BuildFrom(proto, dependencies);
}
}
}
