call.go

/*
 *
 * Copyright 2014 gRPC authors.
 *
 * 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.
 *
 */

package grpc

import (
	"context"
	"fmt"
)

import (
	"github.com/dubbogo/grpc-go/metadata"
)

// Invoke sends the RPC request on the wire and returns after response is
// received.  This is typically called by generated code.
//
// All errors returned by Invoke are compatible with the status package.
func (cc *ClientConn) Invoke(ctx context.Context, method string, args, reply interface{}, opts ...CallOption) (metadata.MD, error) {
	// allow interceptor to see all applicable call options, which means those
	// configured as defaults from dial option as well as per-call options
	opts = Combine(cc.dopts.callOptions, opts)

	if cc.dopts.unaryInt != nil {
		return cc.dopts.unaryInt(ctx, method, args, reply, cc, GRPCConnInvokeWithTrailer, opts...)
	}
	return GRPCConnInvokeWithTrailer(ctx, method, args, reply, cc, opts...)
}

func Combine(o1 []CallOption, o2 []CallOption) []CallOption {
	// we don't use append because o1 could have extra capacity whose
	// elements would be overwritten, which could cause inadvertent
	// sharing (and race conditions) between concurrent calls
	if len(o1) == 0 {
		return o2
	} else if len(o2) == 0 {
		return o1
	}
	ret := make([]CallOption, len(o1)+len(o2))
	copy(ret, o1)
	copy(ret[len(o1):], o2)
	return ret
}

// Invoke sends the RPC request on the wire and returns after response is
// received.  This is typically called by generated code.
//
// DEPRECATED: Use ClientConn.Invoke instead.
func Invoke(ctx context.Context, method string, args, reply interface{}, cc *ClientConn, opts ...CallOption) (metadata.MD, error) {
	return cc.Invoke(ctx, method, args, reply, opts...)
}

var unaryStreamDesc = &StreamDesc{ServerStreams: false, ClientStreams: false}

func GRPCConnInvoke(ctx context.Context, method string, req, reply interface{}, cc *ClientConn, opts ...CallOption) error {
	cs, err := newClientStream(ctx, unaryStreamDesc, cc, method, opts...)
	if err != nil {
		return err
	}
	if err := cs.SendMsg(req); err != nil {
		return err
	}
	if err := cs.RecvMsg(reply); err != nil {
		return err
	}
	trailer := cs.Trailer()
	fmt.Println(trailer)
	return nil
}

func GRPCConnInvokeWithTrailer(ctx context.Context, method string, req, reply interface{}, cc *ClientConn, opts ...CallOption) (metadata.MD, error) {
	cs, err := newClientStream(ctx, unaryStreamDesc, cc, method, opts...)
	trailer := make(metadata.MD)
	if err != nil {
		return trailer, err
	}
	if err := cs.SendMsg(req); err != nil {
		return trailer, err
	}
	if err := cs.RecvMsg(reply); err != nil {
		return trailer, err
	}
	trailer = cs.Trailer()
	return trailer, nil
}