| 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
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188 |
1×
539×
44×
4×
3×
1×
12×
2×
2×
1×
2×
2×
1×
19×
19×
1×
27×
27×
27×
27×
26×
26×
27×
1×
11×
11×
11×
11×
11×
13×
13×
11×
11×
11×
7×
7×
7×
7×
4×
1×
8×
3×
4×
1×
1×
4×
3×
3×
3×
1×
2×
1×
1×
3×
1×
5×
4×
2×
4×
1×
6×
6×
26×
10×
1×
9×
5×
6×
1×
12×
14×
5×
5×
5×
5×
5×
1×
9×
12×
24×
10×
8×
12×
12×
2×
1×
1×
2×
12×
1×
4×
4×
3×
1×
| 'use strict';
const _ = require('lodash');
exports.notNull = v => v !== undefined && v !== null;
exports.notEmpty = v => exports.notNull(v) && v.length > 0;
exports.encodeBase64 = s => new Buffer(s, 'utf8').toString('base64');
exports.decodeBase64 = s => new Buffer(s, 'base64').toString('utf8');
exports.decodeJson64 = (json64) => {
if (!exports.notNull(json64)) { return null; }
let np = exports.decodeBase64(json64);
try { return JSON.parse(np); } catch (ex) { return null; }
};
exports.encodeJson64 = (json) => {
Iif (!exports.notNull(json)) { return null; }
return exports.encodeBase64(JSON.stringify(json));
};
// Construct a failure object that can be sent to context.fail()
exports.failure = (code, msg, type) => {
if (!exports.notNull(type)) { type = 'Bad request'; }
return {
statusCode: code,
providerMessage: JSON.stringify(msg),
errorType: type
};
};
// Construct a path from a curly-bars template (like "/abc/{id}/def"),
// and a lookup function that returns the variable values.
exports.constructPath = (tmpl, varLookup) => {
const re = /([^{]*)(?:{([^}]+)})?/g;
let o = '';
let e = null;
while ((e = re.exec(tmpl)) !== null && (e[1] || e[2])) {
o += (e[1] || '');
if (e[2]) { o += (varLookup(e[2]) || ''); }
}
return o;
};
// Given a curly-bars path template (like "/abc/{id}/def") and a path
// that might match it (like "/abc/123/def"), return null if it didn't
// match, or the sub-matches (like {"id": "123"}) if it did.
exports.matchPath = (tmpl, path) => {
// TODO: improve: this is not particularly stable, or flexible
const re = /([^{]*)(?:{([^}]+)})?/g;
let o = '^';
let e = null;
let vnames = [];
while ((e = re.exec(tmpl)) !== null && (e[1] || e[2])) {
o += (e[1] || '');
if (e[2]) { o += '([^/]*)'; vnames.push(e[2]); }
}
let rre = RegExp(o);
let eResult = null;
if ((eResult = rre.exec(path)) !== null) {
let values = {};
for (let i = 0; i < vnames.length; ++i) {
values[vnames[i]] = eResult[i + 1];
}
return values;
} else {
return null;
}
};
// Constructs a context for use by an API Gateway.
exports.apiGateway = (context) => {
return _.assign(_.clone(context), {
succeed: (data) => context.succeed(apiGatewayResponse(data)),
fail: (err) => context.fail(apiGatewayError(err, context)),
done: (err, data) =>
context.done(apiGatewayError(err, context), apiGatewayResponse(data))
});
};
// Morph the response object into something the API Gateway can use.
const apiGatewayResponse = (resp) => {
if (!exports.notNull(resp)) return null;
let headers = resp.headers || {};
let resposeData;
if (exports.notNull(headers["Elements-Next-Page-Token"]) ||
exports.notNull(headers["Elements-Returned-Count"])) {
resposeData = {
data: resp.body,
nextContinuationToken: headers["Elements-Next-Page-Token"],
returnedCount: headers["Elements-Returned-Count"]
};
} else if(_.isArray(resp.body)) {
resposeData = {
data: resp.body,
returnedCount: resp.body.length
};
} else {
resposeData = resp.body;
}
return {
resposeData: resposeData,
resposeHeaders: resp.headers,
status: resp.status
};
};
// Morph the failure object into something that an API Gateway can use.
const apiGatewayError = (err, context) => {
if (!exports.notNull(err)) return null;
if (err.providerMessage && err.providerMessage.length > 1000) {
err.providerMessage = err.providerMessage.substr(0, 997) + '...';
}
return JSON.stringify({
httpStatus: determineStatusCode(err.statusCode),
message: 'Request failed',
providerMessage: err.providerMessage,
errorType: err.errorType,
requestId: context.awsRequestId
});
};
exports.getDeepPropValue = (needle, haystack) => {
let value;
Object.keys(haystack).forEach( (key) => {
if(!exports.notNull(value)) {
if(key === needle) {
value = haystack[needle];
} else if(typeof haystack[key] === 'object') {
value = exports.getDeepPropValue(needle, haystack[key]);
}
}
});
return value;
};
exports.tokenRepl = (o, tokens) => {
const subst = (orig, toks) => {
if (orig.startsWith('{') && orig.indexOf('}') === orig.length - 1) {
let k = orig.substr(1, orig.length - 2);
let val = _.get(toks, k);
// If val is still undefined, try checking in the body
if(!exports.notNull(val)) { val = _.get(toks, `body.${k}`); }
Iif(k === 'pageSize' && (!exports.notNull(val) || isNaN(parseFloat(val)))) { val = 10; } // Add a default pageSize
if (exports.notNull(val)) { return val; }
else { return null; }
}
return orig.replace(/{([^}]*)}/g, (m, k) => toks[k]);
};
const repl = o => {
if (_.isString(o)) { return subst(o, tokens); }
else if (_.isObject(o)) {
return _.each(o, (v, k) => {
const repd = repl(v);
if (exports.notNull(repd)) o[k] = repd;
else {
if (_.isArray(o)) {
o.splice(k, 1);
} else {
delete o[k];
}
}
});
}
else { return o; }
};
return repl(o);
};
const determineStatusCode = (code) => {
const acceptableErrorsCodes = ['200', '400', '401', '403', '404', '405', '409', '500', '502'];
if(acceptableErrorsCodes.indexOf('' + code) !== -1) {
return '' + code;
} else {
return ('' + code).charAt(0) + '00';
}
};
|