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Diffstat (limited to 'src/cpp/client/channel.cc')
| -rw-r--r-- | src/cpp/client/channel.cc | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/src/cpp/client/channel.cc b/src/cpp/client/channel.cc new file mode 100644 index 0000000000..7a7529104f --- /dev/null +++ b/src/cpp/client/channel.cc @@ -0,0 +1,212 @@ +/* + * + * Copyright 2014, Google Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Google Inc. nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ + +#include "src/cpp/client/channel.h" + +#include <chrono> +#include <string> + +#include <grpc/grpc.h> +#include <grpc/support/log.h> +#include <grpc/support/slice.h> +#include <grpc/support/time.h> + +#include "src/cpp/rpc_method.h" +#include "src/cpp/proto/proto_utils.h" +#include "src/cpp/stream/stream_context.h" +#include "src/cpp/util/time.h" +#include <grpc++/config.h> +#include <google/protobuf/message.h> +#include <grpc++/client_context.h> +#include <grpc++/status.h> + +namespace grpc { + +Channel::Channel(const grpc::string& target) : target_(target) { + c_channel_ = grpc_channel_create(target_.c_str(), nullptr); +} + +Channel::~Channel() { grpc_channel_destroy(c_channel_); } + +namespace { +// Poll one event from the compeletion queue. Return false when an error +// occured or the polled type is not expected. If a finished event has been +// polled, set finished and set status if it has not been set. +bool NextEvent(grpc_completion_queue* cq, grpc_completion_type expected_type, + bool* finished, bool* status_set, Status* status, + google::protobuf::Message* result) { + // We rely on the c layer to enforce deadline and thus do not use deadline + // here. + grpc_event* ev = grpc_completion_queue_next(cq, gpr_inf_future); + if (!ev) { + return false; + } + bool ret = ev->type == expected_type; + switch (ev->type) { + case GRPC_INVOKE_ACCEPTED: + ret = ret && (ev->data.invoke_accepted == GRPC_OP_OK); + break; + case GRPC_READ: + ret = ret && (ev->data.read != nullptr); + if (ret && !DeserializeProto(ev->data.read, result)) { + *status_set = true; + *status = + Status(StatusCode::DATA_LOSS, "Failed to parse response proto."); + ret = false; + } + break; + case GRPC_WRITE_ACCEPTED: + ret = ret && (ev->data.write_accepted == GRPC_OP_OK); + break; + case GRPC_FINISH_ACCEPTED: + ret = ret && (ev->data.finish_accepted == GRPC_OP_OK); + break; + case GRPC_CLIENT_METADATA_READ: + break; + case GRPC_FINISHED: + *finished = true; + if (!*status_set) { + *status_set = true; + StatusCode error_code = static_cast<StatusCode>(ev->data.finished.code); + grpc::string details( + ev->data.finished.details ? ev->data.finished.details : ""); + *status = Status(error_code, details); + } + break; + default: + gpr_log(GPR_ERROR, "Dropping unhandled event with type %d", ev->type); + break; + } + grpc_event_finish(ev); + return ret; +} + +// If finished is not true, get final status by polling until a finished +// event is obtained. +void GetFinalStatus(grpc_completion_queue* cq, bool status_set, bool finished, + Status* status) { + while (!finished) { + NextEvent(cq, GRPC_FINISHED, &finished, &status_set, status, nullptr); + } +} + +} // namespace + +// TODO(yangg) more error handling +Status Channel::StartBlockingRpc(const RpcMethod& method, + ClientContext* context, + const google::protobuf::Message& request, + google::protobuf::Message* result) { + Status status; + bool status_set = false; + bool finished = false; + gpr_timespec absolute_deadline; + AbsoluteDeadlineTimepoint2Timespec(context->absolute_deadline(), + &absolute_deadline); + grpc_call* call = grpc_channel_create_call(c_channel_, method.name(), + // FIXME(yangg) + "localhost", absolute_deadline); + context->set_call(call); + grpc_completion_queue* cq = grpc_completion_queue_create(); + context->set_cq(cq); + // add_metadata from context + // + // invoke + GPR_ASSERT(grpc_call_start_invoke(call, cq, call, call, call, + GRPC_WRITE_BUFFER_HINT) == GRPC_CALL_OK); + if (!NextEvent(cq, GRPC_INVOKE_ACCEPTED, &status_set, &finished, &status, + nullptr)) { + GetFinalStatus(cq, finished, status_set, &status); + return status; + } + // write request + grpc_byte_buffer* write_buffer = nullptr; + bool success = SerializeProto(request, &write_buffer); + if (!success) { + grpc_call_cancel(call); + status_set = true; + status = + Status(StatusCode::DATA_LOSS, "Failed to serialize request proto."); + GetFinalStatus(cq, finished, status_set, &status); + return status; + } + GPR_ASSERT(grpc_call_start_write(call, write_buffer, call, + GRPC_WRITE_BUFFER_HINT) == GRPC_CALL_OK); + grpc_byte_buffer_destroy(write_buffer); + if (!NextEvent(cq, GRPC_WRITE_ACCEPTED, &finished, &status_set, &status, + nullptr)) { + GetFinalStatus(cq, finished, status_set, &status); + return status; + } + // writes done + GPR_ASSERT(grpc_call_writes_done(call, call) == GRPC_CALL_OK); + if (!NextEvent(cq, GRPC_FINISH_ACCEPTED, &finished, &status_set, &status, + nullptr)) { + GetFinalStatus(cq, finished, status_set, &status); + return status; + } + // start read metadata + // + if (!NextEvent(cq, GRPC_CLIENT_METADATA_READ, &finished, &status_set, &status, + nullptr)) { + GetFinalStatus(cq, finished, status_set, &status); + return status; + } + // start read + GPR_ASSERT(grpc_call_start_read(call, call) == GRPC_CALL_OK); + if (!NextEvent(cq, GRPC_READ, &finished, &status_set, &status, result)) { + GetFinalStatus(cq, finished, status_set, &status); + return status; + } + // wait status + GetFinalStatus(cq, finished, status_set, &status); + return status; +} + +StreamContextInterface* Channel::CreateStream(const RpcMethod& method, + ClientContext* context, + const google::protobuf::Message* request, + google::protobuf::Message* result) { + gpr_timespec absolute_deadline; + AbsoluteDeadlineTimepoint2Timespec(context->absolute_deadline(), + &absolute_deadline); + grpc_call* call = grpc_channel_create_call(c_channel_, method.name(), + // FIXME(yangg) + "localhost", absolute_deadline); + context->set_call(call); + grpc_completion_queue* cq = grpc_completion_queue_create(); + context->set_cq(cq); + return new StreamContext(method, context, request, result); +} + +} // namespace grpc |