unpkg/modules/utils/npm.js

130 lines
3.4 KiB
JavaScript

import url from 'url';
import https from 'https';
import gunzip from 'gunzip-maybe';
import tar from 'tar-stream';
import LRUCache from 'lru-cache';
import debug from './debug.js';
import bufferStream from './bufferStream.js';
const npmRegistryURL =
process.env.NPM_REGISTRY_URL || 'https://registry.npmjs.org';
const agent = new https.Agent({
keepAlive: true
});
function parseJSON(res) {
return bufferStream(res).then(JSON.parse);
}
export function fetchPackageInfo(packageName) {
return new Promise((accept, reject) => {
const encodedPackageName =
packageName.charAt(0) === '@'
? `@${encodeURIComponent(packageName.substring(1))}`
: encodeURIComponent(packageName);
const infoURL = `${npmRegistryURL}/${encodedPackageName}`;
debug('Fetching package info for %s from %s', packageName, infoURL);
const { hostname, pathname } = url.parse(infoURL);
const options = {
agent: agent,
hostname: hostname,
path: pathname,
headers: {
Accept: 'application/json'
}
};
https
.get(options, async res => {
if (res.statusCode === 200) {
accept(parseJSON(res));
} else if (res.statusCode === 404) {
accept(null);
} else {
const data = await bufferStream(res);
const content = data.toString('utf-8');
const error = new Error(
`Failed to fetch info for ${packageName}\nstatus: ${res.statusCode}\ndata: ${content}`
);
reject(error);
}
})
.on('error', reject);
});
}
export function fetchPackage(packageConfig) {
return new Promise((accept, reject) => {
const tarballURL = packageConfig.dist.tarball;
debug('Fetching package for %s from %s', packageConfig.name, tarballURL);
const { hostname, pathname } = url.parse(tarballURL);
const options = {
agent: agent,
hostname: hostname,
path: pathname
};
https
.get(options, async res => {
if (res.statusCode === 200) {
accept(res.pipe(gunzip()).pipe(tar.extract()));
} else {
const data = await bufferStream(res);
const spec = `${packageConfig.name}@${packageConfig.version}`;
const content = data.toString('utf-8');
const error = new Error(
`Failed to fetch tarball for ${spec}\nstatus: ${res.statusCode}\ndata: ${content}`
);
reject(error);
}
})
.on('error', reject);
});
}
const oneMegabyte = 1024 * 1024;
const oneSecond = 1000;
const oneMinute = oneSecond * 60;
const cache = new LRUCache({
max: oneMegabyte * 40,
length: Buffer.byteLength,
maxAge: oneSecond
});
const notFound = '';
export async function getPackageInfo(packageName) {
const key = `npmPackageInfo-${packageName}`;
const value = cache.get(key);
if (value != null) {
return value === notFound ? null : JSON.parse(value);
}
const info = await fetchPackageInfo(packageName);
if (info == null) {
// Cache 404s for 5 minutes. This prevents us from making
// unnecessary requests to the registry for bad package names.
// In the worst case, a brand new package's info will be
// available within 5 minutes.
cache.set(key, notFound, oneMinute * 5);
return null;
}
// Cache valid package info for 1 minute. In the worst case,
// new versions won't be available for 1 minute.
cache.set(key, JSON.stringify(info), oneMinute);
return info;
}