blob: 95e8858cffd543a3f60e6e4f6ae00885fabc42af [file] [log] [blame]
/*
* Copyright 2020 Google Inc. All rights reserved.
*
* 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.
*/
/*
* NOTE: The following implementation is a translation for the Swift-grpc
* generator since flatbuffers doesnt allow plugins for now. if an issue arises
* please open an issue in the flatbuffers repository. This file should always
* be maintained according to the Swift-grpc repository
*/
#include <map>
#include <sstream>
#include "flatbuffers/util.h"
#include "src/compiler/schema_interface.h"
#include "src/compiler/swift_generator.h"
namespace grpc_swift_generator {
std::string WrapInNameSpace(const std::vector<std::string> &components, const grpc::string &name) {
std::string qualified_name;
for (auto it = components.begin(); it != components.end(); ++it)
qualified_name += *it + "_";
return qualified_name + name;
}
grpc::string GenerateMessage(const std::vector<std::string> &components, const grpc::string &name) {
return "Message<" + WrapInNameSpace(components, name) + ">";
}
// MARK: - Client
grpc::string GenerateClientFuncName(const grpc_generator::Method *method) {
if (method->NoStreaming()) {
return "$GenAccess$ func $MethodName$(_ request: $Input$"
", callOptions: CallOptions?$isNil$) -> UnaryCall<$Input$,$Output$>";
}
if (method->ClientStreaming()) {
return "$GenAccess$ func $MethodName$"
"(callOptions: CallOptions?$isNil$) -> "
"ClientStreamingCall<$Input$,$Output$>";
}
if (method->ServerStreaming()) {
return "$GenAccess$ func $MethodName$(_ request: $Input$"
", callOptions: CallOptions?$isNil$, handler: @escaping ($Output$"
") -> Void) -> ServerStreamingCall<$Input$, $Output$>";
}
return "$GenAccess$ func $MethodName$"
"(callOptions: CallOptions?$isNil$, handler: @escaping ($Output$"
") -> Void) -> BidirectionalStreamingCall<$Input$, $Output$>";
}
grpc::string GenerateClientFuncBody(const grpc_generator::Method *method) {
if (method->NoStreaming()) {
return "return self.makeUnaryCall(path: "
"\"/$PATH$$ServiceName$/$MethodName$\", request: request, "
"callOptions: callOptions ?? self.defaultCallOptions)";
}
if (method->ClientStreaming()) {
return "return self.makeClientStreamingCall(path: "
"\"/$PATH$$ServiceName$/$MethodName$\", callOptions: callOptions ?? "
"self.defaultCallOptions)";
}
if (method->ServerStreaming()) {
return "return self.makeServerStreamingCall(path: "
"\"/$PATH$$ServiceName$/$MethodName$\", request: request, "
"callOptions: callOptions ?? self.defaultCallOptions, handler: "
"handler)";
}
return "return self.makeBidirectionalStreamingCall(path: "
"\"/$PATH$$ServiceName$/$MethodName$\", callOptions: callOptions ?? "
"self.defaultCallOptions, handler: handler)";
}
void GenerateClientProtocol(const grpc_generator::Service *service,
grpc_generator::Printer *printer,
std::map<grpc::string, grpc::string> *dictonary) {
auto vars = *dictonary;
printer->Print(vars, "$ACCESS$ protocol $ServiceQualifiedName$Service {\n");
vars["GenAccess"] = "";
for (auto it = 0; it < service->method_count(); it++) {
auto method = service->method(it);
vars["Input"] = GenerateMessage(method->get_input_namespace_parts(), method->get_input_type_name());
vars["Output"] = GenerateMessage(method->get_output_namespace_parts(), method->get_output_type_name());
vars["MethodName"] = method->name();
vars["isNil"] = "";
printer->Print(" ");
auto func = GenerateClientFuncName(method.get());
printer->Print(vars, func.c_str());
printer->Print("\n");
}
printer->Print("}\n\n");
}
void GenerateClientClass(const grpc_generator::Service *service,
grpc_generator::Printer *printer,
std::map<grpc::string, grpc::string> *dictonary) {
auto vars = *dictonary;
printer->Print(vars,
"$ACCESS$ final class $ServiceQualifiedName$ServiceClient: GRPCClient, "
"$ServiceQualifiedName$Service {\n");
printer->Print(vars, " $ACCESS$ let channel: GRPCChannel\n");
printer->Print(vars, " $ACCESS$ var defaultCallOptions: CallOptions\n");
printer->Print("\n");
printer->Print(vars,
" $ACCESS$ init(channel: GRPCChannel, "
"defaultCallOptions: CallOptions = CallOptions()) {\n");
printer->Print(" self.channel = channel\n");
printer->Print(" self.defaultCallOptions = defaultCallOptions\n");
printer->Print(" }");
printer->Print("\n");
vars["GenAccess"] = service->is_internal() ? "internal" : "public";
for (auto it = 0; it < service->method_count(); it++) {
auto method = service->method(it);
vars["Input"] = GenerateMessage(method->get_input_namespace_parts(), method->get_input_type_name());
vars["Output"] = GenerateMessage(method->get_output_namespace_parts(), method->get_output_type_name());
vars["MethodName"] = method->name();
vars["isNil"] = " = nil";
printer->Print("\n ");
auto func = GenerateClientFuncName(method.get());
printer->Print(vars, func.c_str());
printer->Print(" {\n");
auto body = GenerateClientFuncBody(method.get());
printer->Print(" ");
printer->Print(vars, body.c_str());
printer->Print("\n }\n");
}
printer->Print("}\n");
}
// MARK: - Server
grpc::string GenerateServerFuncName(const grpc_generator::Method *method) {
if (method->NoStreaming()) {
return "func $MethodName$(_ request: $Input$"
", context: StatusOnlyCallContext) -> EventLoopFuture<$Output$>";
}
if (method->ClientStreaming()) {
return "func $MethodName$(context: UnaryResponseCallContext<$Output$>) -> "
"EventLoopFuture<(StreamEvent<$Input$"
">) -> Void>";
}
if (method->ServerStreaming()) {
return "func $MethodName$(request: $Input$"
", context: StreamingResponseCallContext<$Output$>) -> "
"EventLoopFuture<GRPCStatus>";
}
return "func $MethodName$(context: StreamingResponseCallContext<$Output$>) "
"-> EventLoopFuture<(StreamEvent<$Input$>) -> Void>";
}
grpc::string GenerateServerExtensionBody(const grpc_generator::Method *method) {
grpc::string start = " case \"$MethodName$\":\n ";
if (method->NoStreaming()) {
return start +
"return CallHandlerFactory.makeUnary(callHandlerContext: callHandlerContext) { "
"context in"
"\n "
"return { request in"
"\n "
"self.$MethodName$(request, context: context)"
"\n }"
"\n }";
}
if (method->ClientStreaming()) {
return start +
"return CallHandlerFactory.makeClientStreaming(callHandlerContext: "
"callHandlerContext) { context in"
"\n "
"self.$MethodName$(context: context)"
"\n }";
}
if (method->ServerStreaming()) {
return start +
"return CallHandlerFactory.makeServerStreaming(callHandlerContext: "
"callHandlerContext) { context in"
"\n "
"return { request in"
"\n "
"self.$MethodName$(request: request, context: context)"
"\n }"
"\n }";
}
if (method->BidiStreaming()) {
return start +
"return CallHandlerFactory.makeBidirectionalStreaming(callHandlerContext: "
"callHandlerContext) { context in"
"\n "
"self.$MethodName$(context: context)"
"\n }";
}
return "";
}
void GenerateServerProtocol(const grpc_generator::Service *service,
grpc_generator::Printer *printer,
std::map<grpc::string, grpc::string> *dictonary) {
auto vars = *dictonary;
printer->Print(
vars, "$ACCESS$ protocol $ServiceQualifiedName$Provider: CallHandlerProvider {\n");
for (auto it = 0; it < service->method_count(); it++) {
auto method = service->method(it);
vars["Input"] = GenerateMessage(method->get_input_namespace_parts(), method->get_input_type_name());
vars["Output"] = GenerateMessage(method->get_output_namespace_parts(), method->get_output_type_name());
vars["MethodName"] = method->name();
printer->Print(" ");
auto func = GenerateServerFuncName(method.get());
printer->Print(vars, func.c_str());
printer->Print("\n");
}
printer->Print("}\n\n");
printer->Print(vars, "$ACCESS$ extension $ServiceQualifiedName$Provider {\n");
printer->Print("\n");
printer->Print(vars,
" var serviceName: Substring { return "
"\"$PATH$$ServiceName$\" }\n");
printer->Print("\n");
printer->Print(
" func handleMethod(_ methodName: Substring, callHandlerContext: "
"CallHandlerContext) -> GRPCCallHandler? {\n");
printer->Print(" switch methodName {\n");
for (auto it = 0; it < service->method_count(); it++) {
auto method = service->method(it);
vars["Input"] = GenerateMessage(method->get_input_namespace_parts(), method->get_input_type_name());
vars["Output"] = GenerateMessage(method->get_output_namespace_parts(), method->get_output_type_name());
vars["MethodName"] = method->name();
auto body = GenerateServerExtensionBody(method.get());
printer->Print(vars, body.c_str());
printer->Print("\n");
}
printer->Print(" default: return nil;\n");
printer->Print(" }\n");
printer->Print(" }\n\n");
printer->Print("}");
}
grpc::string Generate(grpc_generator::File *file,
const grpc_generator::Service *service) {
grpc::string output;
std::map<grpc::string, grpc::string> vars;
vars["PATH"] = file->package();
if (!file->package().empty()) { vars["PATH"].append("."); }
vars["ServiceQualifiedName"] = WrapInNameSpace(service->namespace_parts(), service->name());
vars["ServiceName"] = service->name();
vars["ACCESS"] = service->is_internal() ? "internal" : "public";
auto printer = file->CreatePrinter(&output);
printer->Print(vars,
"/// Usage: instantiate $ServiceQualifiedName$ServiceClient, then call "
"methods of this protocol to make API calls.\n");
GenerateClientProtocol(service, &*printer, &vars);
GenerateClientClass(service, &*printer, &vars);
printer->Print("\n");
GenerateServerProtocol(service, &*printer, &vars);
return output;
}
grpc::string GenerateHeader() {
grpc::string code;
code +=
"/// The following code is generated by the Flatbuffers library which "
"might not be in sync with grpc-swift\n";
code +=
"/// in case of an issue please open github issue, though it would be "
"maintained\n";
code += "\n";
code += "// swiftlint:disable all\n";
code += "// swiftformat:disable all\n";
code += "\n";
code += "import Foundation\n";
code += "import GRPC\n";
code += "import NIO\n";
code += "import NIOHTTP1\n";
code += "import FlatBuffers\n";
code += "\n";
code +=
"public protocol GRPCFlatBufPayload: GRPCPayload, FlatBufferGRPCMessage "
"{}\n";
code += "public extension GRPCFlatBufPayload {\n";
code += " init(serializedByteBuffer: inout NIO.ByteBuffer) throws {\n";
code +=
" self.init(byteBuffer: FlatBuffers.ByteBuffer(contiguousBytes: "
"serializedByteBuffer.readableBytesView, count: "
"serializedByteBuffer.readableBytes))\n";
code += " }\n";
code += " func serialize(into buffer: inout NIO.ByteBuffer) throws {\n";
code +=
" let buf = UnsafeRawBufferPointer(start: self.rawPointer, count: "
"Int(self.size))\n";
code += " buffer.writeBytes(buf)\n";
code += " }\n";
code += "}\n";
code += "extension Message: GRPCFlatBufPayload {}\n";
return code;
}
} // namespace grpc_swift_generator