1/*
2 *
3 * Copyright 2014 gRPC authors.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 */
18
19package grpc
20
21import (
22	"context"
23)
24
25// Invoke sends the RPC request on the wire and returns after response is
26// received.  This is typically called by generated code.
27//
28// All errors returned by Invoke are compatible with the status package.
29func (cc *ClientConn) Invoke(ctx context.Context, method string, args, reply interface{}, opts ...CallOption) error {
30	// allow interceptor to see all applicable call options, which means those
31	// configured as defaults from dial option as well as per-call options
32	opts = combine(cc.dopts.callOptions, opts)
33
34	if cc.dopts.unaryInt != nil {
35		return cc.dopts.unaryInt(ctx, method, args, reply, cc, invoke, opts...)
36	}
37	return invoke(ctx, method, args, reply, cc, opts...)
38}
39
40func combine(o1 []CallOption, o2 []CallOption) []CallOption {
41	// we don't use append because o1 could have extra capacity whose
42	// elements would be overwritten, which could cause inadvertent
43	// sharing (and race conditions) between concurrent calls
44	if len(o1) == 0 {
45		return o2
46	} else if len(o2) == 0 {
47		return o1
48	}
49	ret := make([]CallOption, len(o1)+len(o2))
50	copy(ret, o1)
51	copy(ret[len(o1):], o2)
52	return ret
53}
54
55// Invoke sends the RPC request on the wire and returns after response is
56// received.  This is typically called by generated code.
57//
58// DEPRECATED: Use ClientConn.Invoke instead.
59func Invoke(ctx context.Context, method string, args, reply interface{}, cc *ClientConn, opts ...CallOption) error {
60	return cc.Invoke(ctx, method, args, reply, opts...)
61}
62
63var unaryStreamDesc = &StreamDesc{ServerStreams: false, ClientStreams: false}
64
65func invoke(ctx context.Context, method string, req, reply interface{}, cc *ClientConn, opts ...CallOption) error {
66	cs, err := newClientStream(ctx, unaryStreamDesc, cc, method, opts...)
67	if err != nil {
68		return err
69	}
70	if err := cs.SendMsg(req); err != nil {
71		return err
72	}
73	return cs.RecvMsg(reply)
74}
75