1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
|
/*
*
* Copyright 2015, 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.
*
*/
'use strict';
var grpc = require('../..');
var math = grpc.load(__dirname + '/../../../proto/math/math.proto').math;
/**
* Server function for division. Provides the /Math/DivMany and /Math/Div
* functions (Div is just DivMany with only one stream element). For each
* DivArgs parameter, responds with a DivReply with the results of the division
* @param {Object} call The object containing request and cancellation info
* @param {function(Error, *)} cb Response callback
*/
function mathDiv(call, cb) {
var req = call.request;
// Unary + is explicit coersion to integer
if (+req.divisor === 0) {
cb(new Error('cannot divide by zero'));
} else {
cb(null, {
quotient: req.dividend / req.divisor,
remainder: req.dividend % req.divisor
});
}
}
/**
* Server function for Fibonacci numbers. Provides the /Math/Fib function. Reads
* a single parameter that indicates the number of responses, and then responds
* with a stream of that many Fibonacci numbers.
* @param {stream} stream The stream for sending responses.
*/
function mathFib(stream) {
// Here, call is a standard writable Node object Stream
var previous = 0, current = 1;
for (var i = 0; i < stream.request.limit; i++) {
stream.write({num: current});
var temp = current;
current += previous;
previous = temp;
}
stream.end();
}
/**
* Server function for summation. Provides the /Math/Sum function. Reads a
* stream of number parameters, then responds with their sum.
* @param {stream} call The stream of arguments.
* @param {function(Error, *)} cb Response callback
*/
function mathSum(call, cb) {
// Here, call is a standard readable Node object Stream
var sum = 0;
call.on('data', function(data) {
sum += (+data.num);
});
call.on('end', function() {
cb(null, {num: sum});
});
}
function mathDivMany(stream) {
stream.on('data', function(div_args) {
if (+div_args.divisor === 0) {
stream.emit('error', new Error('cannot divide by zero'));
} else {
stream.write({
quotient: div_args.dividend / div_args.divisor,
remainder: div_args.dividend % div_args.divisor
});
}
});
stream.on('end', function() {
stream.end();
});
}
function getMathServer() {
var server = new grpc.Server();
server.addProtoService(math.Math.service, {
div: mathDiv,
fib: mathFib,
sum: mathSum,
divMany: mathDivMany
});
return server;
}
if (require.main === module) {
var server = getMathServer();
server.bind('0.0.0.0:50051', grpc.ServerCredentials.createInsecure());
server.start();
}
/**
* See docs for server
*/
module.exports = getMathServer;
|
