trouble-in-terror-town/node_modules/cacache/lib/entry-index.js
Mikolaj 2bbacbea09 did some more work on networking and removed EOS in favor of LRM
did some more work on networking and removed EOS in favor of Light Reflective Mirror
2022-05-31 15:04:31 +02:00

403 lines
11 KiB
JavaScript

'use strict'
const util = require('util')
const crypto = require('crypto')
const fs = require('@npmcli/fs')
const Minipass = require('minipass')
const path = require('path')
const ssri = require('ssri')
const uniqueFilename = require('unique-filename')
const contentPath = require('./content/path')
const fixOwner = require('./util/fix-owner')
const hashToSegments = require('./util/hash-to-segments')
const indexV = require('../package.json')['cache-version'].index
const moveFile = require('@npmcli/move-file')
const _rimraf = require('rimraf')
const rimraf = util.promisify(_rimraf)
rimraf.sync = _rimraf.sync
module.exports.NotFoundError = class NotFoundError extends Error {
constructor (cache, key) {
super(`No cache entry for ${key} found in ${cache}`)
this.code = 'ENOENT'
this.cache = cache
this.key = key
}
}
module.exports.compact = compact
async function compact (cache, key, matchFn, opts = {}) {
const bucket = bucketPath(cache, key)
const entries = await bucketEntries(bucket)
const newEntries = []
// we loop backwards because the bottom-most result is the newest
// since we add new entries with appendFile
for (let i = entries.length - 1; i >= 0; --i) {
const entry = entries[i]
// a null integrity could mean either a delete was appended
// or the user has simply stored an index that does not map
// to any content. we determine if the user wants to keep the
// null integrity based on the validateEntry function passed in options.
// if the integrity is null and no validateEntry is provided, we break
// as we consider the null integrity to be a deletion of everything
// that came before it.
if (entry.integrity === null && !opts.validateEntry) {
break
}
// if this entry is valid, and it is either the first entry or
// the newEntries array doesn't already include an entry that
// matches this one based on the provided matchFn, then we add
// it to the beginning of our list
if ((!opts.validateEntry || opts.validateEntry(entry) === true) &&
(newEntries.length === 0 ||
!newEntries.find((oldEntry) => matchFn(oldEntry, entry)))) {
newEntries.unshift(entry)
}
}
const newIndex = '\n' + newEntries.map((entry) => {
const stringified = JSON.stringify(entry)
const hash = hashEntry(stringified)
return `${hash}\t${stringified}`
}).join('\n')
const setup = async () => {
const target = uniqueFilename(path.join(cache, 'tmp'), opts.tmpPrefix)
await fixOwner.mkdirfix(cache, path.dirname(target))
return {
target,
moved: false,
}
}
const teardown = async (tmp) => {
if (!tmp.moved) {
return rimraf(tmp.target)
}
}
const write = async (tmp) => {
await fs.writeFile(tmp.target, newIndex, { flag: 'wx' })
await fixOwner.mkdirfix(cache, path.dirname(bucket))
// we use @npmcli/move-file directly here because we
// want to overwrite the existing file
await moveFile(tmp.target, bucket)
tmp.moved = true
try {
await fixOwner.chownr(cache, bucket)
} catch (err) {
if (err.code !== 'ENOENT') {
throw err
}
}
}
// write the file atomically
const tmp = await setup()
try {
await write(tmp)
} finally {
await teardown(tmp)
}
// we reverse the list we generated such that the newest
// entries come first in order to make looping through them easier
// the true passed to formatEntry tells it to keep null
// integrity values, if they made it this far it's because
// validateEntry returned true, and as such we should return it
return newEntries.reverse().map((entry) => formatEntry(cache, entry, true))
}
module.exports.insert = insert
async function insert (cache, key, integrity, opts = {}) {
const { metadata, size } = opts
const bucket = bucketPath(cache, key)
const entry = {
key,
integrity: integrity && ssri.stringify(integrity),
time: Date.now(),
size,
metadata,
}
try {
await fixOwner.mkdirfix(cache, path.dirname(bucket))
const stringified = JSON.stringify(entry)
// NOTE - Cleverness ahoy!
//
// This works because it's tremendously unlikely for an entry to corrupt
// another while still preserving the string length of the JSON in
// question. So, we just slap the length in there and verify it on read.
//
// Thanks to @isaacs for the whiteboarding session that ended up with
// this.
await fs.appendFile(bucket, `\n${hashEntry(stringified)}\t${stringified}`)
await fixOwner.chownr(cache, bucket)
} catch (err) {
if (err.code === 'ENOENT') {
return undefined
}
throw err
// There's a class of race conditions that happen when things get deleted
// during fixOwner, or between the two mkdirfix/chownr calls.
//
// It's perfectly fine to just not bother in those cases and lie
// that the index entry was written. Because it's a cache.
}
return formatEntry(cache, entry)
}
module.exports.insert.sync = insertSync
function insertSync (cache, key, integrity, opts = {}) {
const { metadata, size } = opts
const bucket = bucketPath(cache, key)
const entry = {
key,
integrity: integrity && ssri.stringify(integrity),
time: Date.now(),
size,
metadata,
}
fixOwner.mkdirfix.sync(cache, path.dirname(bucket))
const stringified = JSON.stringify(entry)
fs.appendFileSync(bucket, `\n${hashEntry(stringified)}\t${stringified}`)
try {
fixOwner.chownr.sync(cache, bucket)
} catch (err) {
if (err.code !== 'ENOENT') {
throw err
}
}
return formatEntry(cache, entry)
}
module.exports.find = find
async function find (cache, key) {
const bucket = bucketPath(cache, key)
try {
const entries = await bucketEntries(bucket)
return entries.reduce((latest, next) => {
if (next && next.key === key) {
return formatEntry(cache, next)
} else {
return latest
}
}, null)
} catch (err) {
if (err.code === 'ENOENT') {
return null
} else {
throw err
}
}
}
module.exports.find.sync = findSync
function findSync (cache, key) {
const bucket = bucketPath(cache, key)
try {
return bucketEntriesSync(bucket).reduce((latest, next) => {
if (next && next.key === key) {
return formatEntry(cache, next)
} else {
return latest
}
}, null)
} catch (err) {
if (err.code === 'ENOENT') {
return null
} else {
throw err
}
}
}
module.exports.delete = del
function del (cache, key, opts = {}) {
if (!opts.removeFully) {
return insert(cache, key, null, opts)
}
const bucket = bucketPath(cache, key)
return rimraf(bucket)
}
module.exports.delete.sync = delSync
function delSync (cache, key, opts = {}) {
if (!opts.removeFully) {
return insertSync(cache, key, null, opts)
}
const bucket = bucketPath(cache, key)
return rimraf.sync(bucket)
}
module.exports.lsStream = lsStream
function lsStream (cache) {
const indexDir = bucketDir(cache)
const stream = new Minipass({ objectMode: true })
// Set all this up to run on the stream and then just return the stream
Promise.resolve().then(async () => {
const buckets = await readdirOrEmpty(indexDir)
await Promise.all(buckets.map(async (bucket) => {
const bucketPath = path.join(indexDir, bucket)
const subbuckets = await readdirOrEmpty(bucketPath)
await Promise.all(subbuckets.map(async (subbucket) => {
const subbucketPath = path.join(bucketPath, subbucket)
// "/cachename/<bucket 0xFF>/<bucket 0xFF>./*"
const subbucketEntries = await readdirOrEmpty(subbucketPath)
await Promise.all(subbucketEntries.map(async (entry) => {
const entryPath = path.join(subbucketPath, entry)
try {
const entries = await bucketEntries(entryPath)
// using a Map here prevents duplicate keys from showing up
// twice, I guess?
const reduced = entries.reduce((acc, entry) => {
acc.set(entry.key, entry)
return acc
}, new Map())
// reduced is a map of key => entry
for (const entry of reduced.values()) {
const formatted = formatEntry(cache, entry)
if (formatted) {
stream.write(formatted)
}
}
} catch (err) {
if (err.code === 'ENOENT') {
return undefined
}
throw err
}
}))
}))
}))
stream.end()
}).catch(err => stream.emit('error', err))
return stream
}
module.exports.ls = ls
async function ls (cache) {
const entries = await lsStream(cache).collect()
return entries.reduce((acc, xs) => {
acc[xs.key] = xs
return acc
}, {})
}
module.exports.bucketEntries = bucketEntries
async function bucketEntries (bucket, filter) {
const data = await fs.readFile(bucket, 'utf8')
return _bucketEntries(data, filter)
}
module.exports.bucketEntries.sync = bucketEntriesSync
function bucketEntriesSync (bucket, filter) {
const data = fs.readFileSync(bucket, 'utf8')
return _bucketEntries(data, filter)
}
function _bucketEntries (data, filter) {
const entries = []
data.split('\n').forEach((entry) => {
if (!entry) {
return
}
const pieces = entry.split('\t')
if (!pieces[1] || hashEntry(pieces[1]) !== pieces[0]) {
// Hash is no good! Corruption or malice? Doesn't matter!
// EJECT EJECT
return
}
let obj
try {
obj = JSON.parse(pieces[1])
} catch (e) {
// Entry is corrupted!
return
}
if (obj) {
entries.push(obj)
}
})
return entries
}
module.exports.bucketDir = bucketDir
function bucketDir (cache) {
return path.join(cache, `index-v${indexV}`)
}
module.exports.bucketPath = bucketPath
function bucketPath (cache, key) {
const hashed = hashKey(key)
return path.join.apply(
path,
[bucketDir(cache)].concat(hashToSegments(hashed))
)
}
module.exports.hashKey = hashKey
function hashKey (key) {
return hash(key, 'sha256')
}
module.exports.hashEntry = hashEntry
function hashEntry (str) {
return hash(str, 'sha1')
}
function hash (str, digest) {
return crypto
.createHash(digest)
.update(str)
.digest('hex')
}
function formatEntry (cache, entry, keepAll) {
// Treat null digests as deletions. They'll shadow any previous entries.
if (!entry.integrity && !keepAll) {
return null
}
return {
key: entry.key,
integrity: entry.integrity,
path: entry.integrity ? contentPath(cache, entry.integrity) : undefined,
size: entry.size,
time: entry.time,
metadata: entry.metadata,
}
}
function readdirOrEmpty (dir) {
return fs.readdir(dir).catch((err) => {
if (err.code === 'ENOENT' || err.code === 'ENOTDIR') {
return []
}
throw err
})
}