/
req.parameter.mutator.ts
302 lines (277 loc) 路 9.22 KB
/
req.parameter.mutator.ts
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
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
import { Request } from 'express';
import {
OpenAPIV3,
OpenApiRequest,
OpenApiRequestMetadata,
ValidationSchema,
} from '../../framework/types';
import * as url from 'url';
import { validationError } from '../util';
import { dereferenceParameter, normalizeParameter } from './util';
import * as mediaTypeParser from 'media-typer';
import * as contentTypeParser from 'content-type';
type SchemaObject = OpenAPIV3.SchemaObject;
type ReferenceObject = OpenAPIV3.ReferenceObject;
type ParameterObject = OpenAPIV3.ParameterObject;
const RESERVED_CHARS = /[\:\/\?#\[\]@!\$&\'()\*\+,;=]/;
const ARRAY_DELIMITER = {
form: ',',
spaceDelimited: ' ',
pipeDelimited: '|',
};
const REQUEST_FIELDS = {
query: 'query',
header: 'headers',
path: 'params',
cookie: 'cookies',
};
type Schema = ReferenceObject | SchemaObject;
type Parameter = ReferenceObject | ParameterObject;
/**
* A class top parse and mutate the incoming request parameters according to the openapi spec.
* the request is mutated to accomodate various styles and types e.g. form, explode, deepObject, etc
*/
export class RequestParameterMutator {
private _apiDocs: OpenAPIV3.Document;
private path: string;
private parsedSchema: ValidationSchema;
constructor(
apiDocs: OpenAPIV3.Document,
path: string,
parsedSchema: ValidationSchema,
) {
this._apiDocs = apiDocs;
this.path = path;
this.parsedSchema = parsedSchema;
}
/**
* Modifies an incoing request object by applying the openapi schema
* req values may be parsed/mutated as a JSON object, JSON Exploded Object, JSON Array, or JSON Exploded Array
* @param req
*/
public modifyRequest(req: OpenApiRequest): void {
const { parameters } = (<OpenApiRequestMetadata>req.openapi).schema;
const rawQuery = this.parseQueryStringUndecoded(
url.parse(req.originalUrl).query,
);
parameters.forEach(p => {
const parameter = dereferenceParameter(this._apiDocs, p);
const { name, schema } = normalizeParameter(parameter);
const { type } = <SchemaObject>schema;
const { style, explode } = parameter;
const i = req.originalUrl.indexOf('?');
const queryString = req.originalUrl.substr(i + 1);
if (parameter.in === 'query' && !parameter.allowReserved) {
this.validateReservedCharacters(name, rawQuery);
}
if (parameter.content) {
this.handleContent(req, name, parameter);
} else if (parameter.in === 'query' && this.isObjectOrXOf(schema)) {
this.parseJsonAndMutateRequest(req, parameter.in, name);
if (style === 'form' && explode) {
this.handleFormExplode(req, name, <SchemaObject>schema, parameter);
} else if (style === 'deepObject') {
this.handleDeepObject(req, queryString, name);
}
} else if (type === 'array' && !explode) {
const delimiter = ARRAY_DELIMITER[parameter.style];
this.validateArrayDelimiter(delimiter, parameter);
this.parseJsonArrayAndMutateRequest(req, parameter.in, name, delimiter);
} else if (type === 'array' && explode) {
this.explodeJsonArrayAndMutateRequest(req, parameter.in, name);
} else if (style === 'form' && explode) {
this.handleFormExplode(req, name, <SchemaObject>schema, parameter);
}
});
}
private handleDeepObject(req: Request, qs: string, name: string): void {
// nothing to do
// TODO handle url encoded?
}
private handleContent(
req: Request,
name: string,
parameter: ParameterObject,
): void {
/**
* Per the OpenAPI3 spec:
* A map containing the representations for the parameter. The key is the media type
* and the value describes it. The map MUST only contain one entry.
* https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#parameterContent
*/
const contentType = Object.keys(parameter.content)[0];
const parsedContentType = contentTypeParser.parse(contentType);
const parsedMediaType = mediaTypeParser.parse(parsedContentType.type);
const { subtype, suffix } = parsedMediaType;
const isMediaTypeJson = [subtype, suffix].includes('json');
if (isMediaTypeJson) {
const reqField = REQUEST_FIELDS[parameter.in];
this.parseJsonAndMutateRequest(req, reqField, name);
}
}
private handleFormExplode(
req: Request,
name: string,
schema: SchemaObject,
parameter: ParameterObject,
): void {
// fetch the keys used for this kind of explode
const type = schema.type;
const hasXOf = schema.allOf || schema.oneOf || schema.anyOf;
const properties = hasXOf
? xOfProperties(schema)
: type === 'object'
? Object.keys(schema.properties)
: [];
this.explodedJsonObjectAndMutateRequest(
req,
parameter.in,
name,
properties,
schema,
);
function xOfProperties(schema: Schema): string[] {
return ['allOf', 'oneOf', 'anyOf'].reduce((acc, key) => {
if (!schema.hasOwnProperty(key)) {
return acc;
} else {
const foundProperties = schema[key].reduce((acc2, obj) => {
return obj.type === 'object'
? acc2.concat(...Object.keys(obj.properties))
: acc2;
}, []);
return foundProperties.length > 0
? acc.concat(...foundProperties)
: acc;
}
}, []);
}
}
private parseJsonAndMutateRequest(
req: Request,
$in: string,
name: string,
): void {
/**
* support json in request params, query, headers and cookies
* like this filter={"type":"t-shirt","color":"blue"}
*
* https://swagger.io/docs/specification/describing-parameters/#schema-vs-content
*/
const field = REQUEST_FIELDS[$in];
if (req[field]?.[name]) {
try {
const value = req[field][name];
const json = JSON.parse(value);
req[field][name] = json;
} catch (e) {
// NOOP If parsing failed but _should_ contain JSON, validator will catch it.
// May contain falsely flagged parameter (e.g. input was object OR string)
}
}
}
private parseJsonArrayAndMutateRequest(
req: Request,
$in: string,
name: string,
delimiter: string,
): void {
/**
* array deserialization
* filter=foo,bar,baz
* filter=foo|bar|baz
* filter=foo%20bar%20baz
*/
const field = REQUEST_FIELDS[$in];
if (req[field]?.[name]) {
const value = req[field][name].split(delimiter);
req[field][name] = value;
}
}
private explodedJsonObjectAndMutateRequest(
req: Request,
$in: string,
name: string,
properties: string[],
schema: SchemaObject,
): void {
// forcing convert to object if scheme describes param as object + explode
// for easy validation, keep the schema but update whereabouts of its sub components
const field = REQUEST_FIELDS[$in];
if (req[field]) {
// check if there is at least one of the nested properties before create the parent
const atLeastOne = properties.some(p => req[field].hasOwnProperty(p));
if (atLeastOne) {
req[field][name] = {};
properties.forEach(property => {
if (req[field][property]) {
const schema = this.parsedSchema[field];
const type = schema.properties[name].properties?.[property]?.type;
const value = req[field][property];
const coercedValue =
type === 'array' && !Array.isArray(value) ? [value] : value;
req[field][name][property] = coercedValue;
delete req[field][property];
}
});
}
}
}
private explodeJsonArrayAndMutateRequest(
req: Request,
$in: string,
name: string,
): void {
/**
* forcing convert to array if scheme describes param as array + explode
*/
const field = REQUEST_FIELDS[$in];
if (req[field]?.[name] && !(req[field][name] instanceof Array)) {
const value = [req[field][name]];
req[field][name] = value;
}
}
private isObjectOrXOf(schema: Schema): boolean {
const schemaHasObject = schema => {
if (!schema) return false;
const { type, allOf, oneOf, anyOf } = schema;
return (
type === 'object' ||
[].concat(allOf, oneOf, anyOf).some(schemaHasObject)
);
};
return schemaHasObject(schema);
}
private validateArrayDelimiter(
delimiter: string,
parameter: ParameterObject,
): void {
if (!delimiter) {
const message = `Parameter 'style' has incorrect value '${parameter.style}' for [${parameter.name}]`;
throw validationError(400, `.query.${parameter.name}`, message);
}
}
private validateReservedCharacters(
name: string,
pairs: { [key: string]: string[] },
) {
const vs = pairs[name];
if (!vs) return;
for (const v of vs) {
if (v?.match(RESERVED_CHARS)) {
const message = `Parameter '${name}' must be url encoded. It's value may not contain reserved characters.`;
throw validationError(400, `.query.${name}`, message);
}
}
}
private parseQueryStringUndecoded(qs: string) {
if (!qs) return {};
const q = qs.replace('?', '');
return q.split('&').reduce((m, p) => {
const [k, v] = p.split('=');
m[k] = m[k] ?? [];
m[k].push(v);
return m;
}, {});
}
}