@whatwg-node/node-fetch
Version:
Fetch API implementation for Node
142 lines (141 loc) • 6.17 kB
JavaScript
import { request as httpRequest, STATUS_CODES } from 'node:http';
import { request as httpsRequest } from 'node:https';
import { PassThrough, Readable } from 'node:stream';
import { createBrotliDecompress, createGunzip, createInflate, createInflateRaw } from 'node:zlib';
import { handleMaybePromise } from '@whatwg-node/promise-helpers';
import { PonyfillRequest } from './Request.js';
import { PonyfillResponse } from './Response.js';
import { PonyfillURL } from './URL.js';
import { endStream, getHeadersObj, isNodeReadable, pipeThrough, safeWrite, shouldRedirect, } from './utils.js';
function getRequestFnForProtocol(url) {
if (url.startsWith('http:')) {
return httpRequest;
}
else if (url.startsWith('https:')) {
return httpsRequest;
}
throw new Error(`Unsupported protocol: ${url.split(':')[0] || url}`);
}
export function fetchNodeHttp(fetchRequest) {
return new Promise((resolve, reject) => {
try {
const requestFn = getRequestFnForProtocol(fetchRequest.parsedUrl?.protocol || fetchRequest.url);
const headersSerializer = fetchRequest.headersSerializer || getHeadersObj;
const nodeHeaders = headersSerializer(fetchRequest.headers);
nodeHeaders['accept-encoding'] ||= 'gzip, deflate, br';
nodeHeaders['user-agent'] ||= 'node';
let signal;
if (fetchRequest._signal == null) {
signal = undefined;
}
else if (fetchRequest._signal) {
signal = fetchRequest._signal;
}
let nodeRequest;
// If it is our ponyfilled Request, it should have `parsedUrl` which is a `URL` object
if (fetchRequest.parsedUrl) {
nodeRequest = requestFn(fetchRequest.parsedUrl, {
method: fetchRequest.method,
headers: nodeHeaders,
signal,
agent: fetchRequest.agent,
});
}
else {
nodeRequest = requestFn(fetchRequest.url, {
method: fetchRequest.method,
headers: nodeHeaders,
signal,
agent: fetchRequest.agent,
});
}
nodeRequest.once('error', reject);
nodeRequest.once('response', nodeResponse => {
let outputStream;
const contentEncoding = nodeResponse.headers['content-encoding'];
switch (contentEncoding) {
case 'x-gzip':
case 'gzip':
outputStream = createGunzip();
break;
case 'x-deflate':
case 'deflate':
outputStream = createInflate();
break;
case 'x-deflate-raw':
case 'deflate-raw':
outputStream = createInflateRaw();
break;
case 'br':
outputStream = createBrotliDecompress();
break;
}
if (nodeResponse.headers.location && shouldRedirect(nodeResponse.statusCode)) {
if (fetchRequest.redirect === 'error') {
const redirectError = new Error('Redirects are not allowed');
reject(redirectError);
nodeResponse.resume();
return;
}
if (fetchRequest.redirect === 'follow') {
const redirectedUrl = new PonyfillURL(nodeResponse.headers.location, fetchRequest.parsedUrl || fetchRequest.url);
const redirectResponse$ = fetchNodeHttp(new PonyfillRequest(redirectedUrl, fetchRequest));
resolve(redirectResponse$.then(redirectResponse => {
redirectResponse.redirected = true;
return redirectResponse;
}));
nodeResponse.resume();
return;
}
}
outputStream ||= new PassThrough();
pipeThrough({
src: nodeResponse,
dest: outputStream,
signal,
onError: e => {
if (!nodeResponse.destroyed) {
nodeResponse.destroy(e);
}
if (!outputStream.destroyed) {
outputStream.destroy(e);
}
reject(e);
},
});
const statusCode = nodeResponse.statusCode || 200;
let statusText = nodeResponse.statusMessage || STATUS_CODES[statusCode];
if (statusText == null) {
statusText = '';
}
const ponyfillResponse = new PonyfillResponse(outputStream || nodeResponse, {
status: statusCode,
statusText,
headers: nodeResponse.headers,
url: fetchRequest.url,
signal,
});
resolve(ponyfillResponse);
});
if (fetchRequest['_buffer'] != null) {
handleMaybePromise(() => safeWrite(fetchRequest['_buffer'], nodeRequest), () => endStream(nodeRequest), reject);
}
else {
const nodeReadable = (fetchRequest.body != null
? isNodeReadable(fetchRequest.body)
? fetchRequest.body
: Readable.from(fetchRequest.body)
: null);
if (nodeReadable) {
nodeReadable.pipe(nodeRequest);
}
else {
endStream(nodeRequest);
}
}
}
catch (e) {
reject(e);
}
});
}