-
Notifications
You must be signed in to change notification settings - Fork 5
/
Watchman.js
158 lines (150 loc) · 5.46 KB
/
Watchman.js
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
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
/**
* Copyright 2019, 2023 IBM Corp. 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.
*/
const RequestLib = require('@razee/request-util');
const validUrl = require('valid-url');
const JSONStream = require('JSONStream');
const delay = require('delay');
const merge = require('deepmerge');
const KubeApiConfig = require('./KubeApiConfig');
module.exports = class Watchman {
constructor(options, objectHandler) {
if ((typeof objectHandler) !== 'function') {
throw 'Watchman objectHandler must be a function.';
}
this._objectHandler = objectHandler;
const kac = KubeApiConfig();
this._requestOptions = merge.all(
[
{
headers: {
'User-Agent': 'razee-watchman'
},
baseUrl: kac.baseUrl, // needs the baseurl for validUrl check, but i dont want the other KubeApiConfig values here so that we can fetch them before each call to watch().
json: true, // Automatically parses the JSON string in the response
resolveWithFullResponse: true,
simple: false
},
options.requestOptions ?? {}
]
);
if ((options.logger) && ((typeof options.logger) !== 'object')) {
throw 'options.logger must be an object.';
}
this._logger = options.logger;
if (!validUrl.isUri(`${this._requestOptions.baseUrl}${this._requestOptions.uri}`) || !this._requestOptions?.uri?.includes('watch')) {
throw `uri '${this._requestOptions.baseUrl}${this._requestOptions.uri}' not valid watch uri.`;
}
this._rewatchOnTimeout = typeof options.rewatchOnTimeout === 'boolean' ? options.rewatchOnTimeout : true;
this._requestStream = undefined;
this._jsonStream = undefined;
this._errors = 0;
this._error = false;
this._watching = false;
}
//private methods
get selfLink() {
return this._requestOptions.uri;
}
get logger() {
return this._logger;
}
get objectHandler() {
return this._objectHandler;
}
get watching() {
return this._watching;
}
get watchStart() {
// Returns the numeric value corresponding to when the watch started — the number of milliseconds elapsed since January 1, 1970 00:00:00 UTC
return this._watchStart;
}
_watchError() {
this._errors++;
this._error = true;
this.end(this._rewatchOnTimeout);
delay(this._errors * 1000).then(() => {
if (this._rewatchOnTimeout)
this.watch();
});
}
// public methods
watch() {
this._logger.debug('Watchman: initializing watch');
this.end(this._rewatchOnTimeout);
this._logger.debug('Watchman: attempting new watch ');
// this._requestOptions must not contain a prior KubeApiConfig(), otherwise the old values will overrite the newly fetched ones
this._requestStream = RequestLib.getStream(merge(KubeApiConfig(), this._requestOptions), this._logger)
.on('response', (response) => {
if (response.statusCode !== 200) {
if (this._logger) {
this._logger.error(`GET ${this._requestOptions.uri} returned ${response.statusCode}`);
}
this._watchError();
} else {
this._logger.debug('Watchman: watch started');
this._watchStart = Date.now();
this._watching = true;
this._error = false;
}
})
.on('error', (err) => {
if (this._logger) {
this._logger.error(`GET ${this._requestOptions.uri} errored`, err);
}
this._watchError();
})
.on('close', () => {
this._watching = false;
if (!this._error) {
this._errors = 0;
}
if (this._logger) {
this._logger.info(`GET ${this._requestOptions.uri} closed. rewatchOnTimeout: ${this._rewatchOnTimeout}, errors: ${this._errors}`);
}
if (this._rewatchOnTimeout && this._errors == 0) {
this.watch();
}
});
var parser = JSONStream.parse(true);
parser.on('data', (data) => {
if (data.type === 'ERROR') {
if (this._logger) {
this._logger.error(`GET ${this._requestOptions.uri} errored at data.type === ERROR, aborting`, JSON.stringify(data.object));
}
if( this._requestStream && this._requestStream.abort ) this._requestStream.abort(); // During automated test, the call to logger.error will call end() on the Watchman instance, destroying _requestStream
} else {
this.objectHandler(data);
}
});
parser.on('error', (err) => {
if (this._logger) {
this._logger.error(`GET ${this._requestOptions.uri} errored at parser.on error, aborting`, err);
}
this._requestStream.abort();
});
this._jsonStream = this._requestStream.pipe(parser);
}
end(rewatchOnTimeout = false) {
this._logger.debug('Watchman: ending previous watch');
this._watching = false;
this._rewatchOnTimeout = rewatchOnTimeout;
if (this._requestStream) {
this._requestStream.destroy();
}
this._requestStream = undefined;
this._jsonStream = undefined;
}
};