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
|
import { BufReader, UnexpectedEOFError, BufWriter } from "../io/bufio.ts";
import { TextProtoReader } from "../textproto/mod.ts";
import { assert } from "../testing/asserts.ts";
import { encoder } from "../strings/mod.ts";
export function emptyReader(): Deno.Reader {
return {
async read(_: Uint8Array): Promise<number | Deno.EOF> {
return Deno.EOF;
}
};
}
export function bodyReader(contentLength: number, r: BufReader): Deno.Reader {
let totalRead = 0;
let finished = false;
async function read(buf: Uint8Array): Promise<number | Deno.EOF> {
if (finished) return Deno.EOF;
let result: number | Deno.EOF;
const remaining = contentLength - totalRead;
if (remaining >= buf.byteLength) {
result = await r.read(buf);
} else {
const readBuf = buf.subarray(0, remaining);
result = await r.read(readBuf);
}
if (result !== Deno.EOF) {
totalRead += result;
}
finished = totalRead === contentLength;
return result;
}
return { read };
}
export function chunkedBodyReader(h: Headers, r: BufReader): Deno.Reader {
// Based on https://tools.ietf.org/html/rfc2616#section-19.4.6
const tp = new TextProtoReader(r);
let finished = false;
const chunks: Array<{
offset: number;
data: Uint8Array;
}> = [];
async function read(buf: Uint8Array): Promise<number | Deno.EOF> {
if (finished) return Deno.EOF;
const [chunk] = chunks;
if (chunk) {
const chunkRemaining = chunk.data.byteLength - chunk.offset;
const readLength = Math.min(chunkRemaining, buf.byteLength);
for (let i = 0; i < readLength; i++) {
buf[i] = chunk.data[chunk.offset + i];
}
chunk.offset += readLength;
if (chunk.offset === chunk.data.byteLength) {
chunks.shift();
// Consume \r\n;
if ((await tp.readLine()) === Deno.EOF) {
throw new UnexpectedEOFError();
}
}
return readLength;
}
const line = await tp.readLine();
if (line === Deno.EOF) throw new UnexpectedEOFError();
// TODO: handle chunk extension
const [chunkSizeString] = line.split(";");
const chunkSize = parseInt(chunkSizeString, 16);
if (Number.isNaN(chunkSize) || chunkSize < 0) {
throw new Error("Invalid chunk size");
}
if (chunkSize > 0) {
if (chunkSize > buf.byteLength) {
let eof = await r.readFull(buf);
if (eof === Deno.EOF) {
throw new UnexpectedEOFError();
}
const restChunk = new Uint8Array(chunkSize - buf.byteLength);
eof = await r.readFull(restChunk);
if (eof === Deno.EOF) {
throw new UnexpectedEOFError();
} else {
chunks.push({
offset: 0,
data: restChunk
});
}
return buf.byteLength;
} else {
const bufToFill = buf.subarray(0, chunkSize);
const eof = await r.readFull(bufToFill);
if (eof === Deno.EOF) {
throw new UnexpectedEOFError();
}
// Consume \r\n
if ((await tp.readLine()) === Deno.EOF) {
throw new UnexpectedEOFError();
}
return chunkSize;
}
} else {
assert(chunkSize === 0);
// Consume \r\n
if ((await r.readLine()) === Deno.EOF) {
throw new UnexpectedEOFError();
}
await readTrailers(h, r);
finished = true;
return Deno.EOF;
}
}
return { read };
}
const kProhibitedTrailerHeaders = [
"transfer-encoding",
"content-length",
"trailer"
];
/**
* Read trailer headers from reader and append values to headers.
* "trailer" field will be deleted.
* */
export async function readTrailers(
headers: Headers,
r: BufReader
): Promise<void> {
const keys = parseTrailer(headers.get("trailer"));
if (!keys) return;
const tp = new TextProtoReader(r);
const result = await tp.readMIMEHeader();
assert(result != Deno.EOF, "trailer must be set");
for (const [k, v] of result) {
if (!keys.has(k)) {
throw new Error("Undeclared trailer field");
}
keys.delete(k);
headers.append(k, v);
}
assert(keys.size === 0, "Missing trailers");
headers.delete("trailer");
}
function parseTrailer(field: string | null): Set<string> | undefined {
if (field == null) {
return undefined;
}
const keys = field.split(",").map(v => v.trim());
if (keys.length === 0) {
throw new Error("Empty trailer");
}
for (const invalid of kProhibitedTrailerHeaders) {
if (keys.includes(invalid)) {
throw new Error(`Prohibited field for trailer`);
}
}
return new Set(keys);
}
export async function writeChunkedBody(
w: Deno.Writer,
r: Deno.Reader
): Promise<void> {
const writer = BufWriter.create(w);
for await (const chunk of Deno.toAsyncIterator(r)) {
if (chunk.byteLength <= 0) continue;
const start = encoder.encode(`${chunk.byteLength.toString(16)}\r\n`);
const end = encoder.encode("\r\n");
await writer.write(start);
await writer.write(chunk);
await writer.write(end);
}
const endChunk = encoder.encode("0\r\n\r\n");
await writer.write(endChunk);
}
/** write trailer headers to writer. it mostly should be called after writeResponse */
export async function writeTrailers(
w: Deno.Writer,
headers: Headers,
trailers: Headers
): Promise<void> {
const trailer = headers.get("trailer");
if (trailer === null) {
throw new Error('response headers must have "trailer" header field');
}
const transferEncoding = headers.get("transfer-encoding");
if (transferEncoding === null || !transferEncoding.match(/^chunked/)) {
throw new Error(
`trailer headers is only allowed for "transfer-encoding: chunked": got "${transferEncoding}"`
);
}
const writer = BufWriter.create(w);
const trailerHeaderFields = trailer
.split(",")
.map(s => s.trim().toLowerCase());
for (const f of trailerHeaderFields) {
assert(
!kProhibitedTrailerHeaders.includes(f),
`"${f}" is prohibited for trailer header`
);
}
for (const [key, value] of trailers) {
assert(
trailerHeaderFields.includes(key),
`Not trailer header field: ${key}`
);
await writer.write(encoder.encode(`${key}: ${value}\r\n`));
}
await writer.write(encoder.encode("\r\n"));
await writer.flush();
}
|
