AlkantarClanX12
Your IP : 3.144.46.90
'use strict'
const BB = require('bluebird')
const cacheFile = require('npm-cache-filename')
const chownr = BB.promisify(require('chownr'))
const correctMkdir = BB.promisify(require('../utils/correct-mkdir.js'))
const figgyPudding = require('figgy-pudding')
const fs = require('graceful-fs')
const JSONStream = require('JSONStream')
const log = require('npmlog')
const mkdir = BB.promisify(require('mkdirp'))
const ms = require('mississippi')
const npmFetch = require('libnpm/fetch')
const path = require('path')
const sortedUnionStream = require('sorted-union-stream')
const url = require('url')
const writeStreamAtomic = require('fs-write-stream-atomic')
const statAsync = BB.promisify(fs.stat)
const APMOpts = figgyPudding({
cache: {},
registry: {}
})
// Returns a sorted stream of all package metadata. Internally, takes care of
// maintaining its metadata cache and making partial or full remote requests,
// according to staleness, validity, etc.
//
// The local cache must hold certain invariants:
// 1. It must be a proper JSON object
// 2. It must have its keys lexically sorted
// 3. The first entry must be `_updated` with a millisecond timestamp as a val.
// 4. It must include all entries that exist in the metadata endpoint as of
// the value in `_updated`
module.exports = allPackageMetadata
function allPackageMetadata (opts) {
const staleness = opts.staleness
const stream = ms.through.obj()
opts = APMOpts(opts)
const cacheBase = cacheFile(path.resolve(path.dirname(opts.cache)))(url.resolve(opts.registry, '/-/all'))
const cachePath = path.join(cacheBase, '.cache.json')
createEntryStream(
cachePath, staleness, opts
).then(({entryStream, latest, newEntries}) => {
log.silly('all-package-metadata', 'entry stream created')
if (entryStream && newEntries) {
return createCacheWriteStream(cachePath, latest, opts).then(writer => {
log.silly('all-package-metadata', 'output stream created')
ms.pipeline.obj(entryStream, writer, stream)
})
} else if (entryStream) {
ms.pipeline.obj(entryStream, stream)
} else {
stream.emit('error', new Error('No search sources available'))
}
}).catch(err => stream.emit('error', err))
return stream
}
// Creates a stream of the latest available package metadata.
// Metadata will come from a combination of the local cache and remote data.
module.exports._createEntryStream = createEntryStream
function createEntryStream (cachePath, staleness, opts) {
return createCacheEntryStream(
cachePath, opts
).catch(err => {
log.warn('', 'Failed to read search cache. Rebuilding')
log.silly('all-package-metadata', 'cache read error: ', err)
return {}
}).then(({
updateStream: cacheStream,
updatedLatest: cacheLatest
}) => {
cacheLatest = cacheLatest || 0
return createEntryUpdateStream(staleness, cacheLatest, opts).catch(err => {
log.warn('', 'Search data request failed, search might be stale')
log.silly('all-package-metadata', 'update request error: ', err)
return {}
}).then(({updateStream, updatedLatest}) => {
updatedLatest = updatedLatest || 0
const latest = updatedLatest || cacheLatest
if (!cacheStream && !updateStream) {
throw new Error('No search sources available')
}
if (cacheStream && updateStream) {
// Deduped, unioned, sorted stream from the combination of both.
return {
entryStream: createMergedStream(cacheStream, updateStream),
latest,
newEntries: !!updatedLatest
}
} else {
// Either one works if one or the other failed
return {
entryStream: cacheStream || updateStream,
latest,
newEntries: !!updatedLatest
}
}
})
})
}
// Merges `a` and `b` into one stream, dropping duplicates in favor of entries
// in `b`. Both input streams should already be individually sorted, and the
// returned output stream will have semantics resembling the merge step of a
// plain old merge sort.
module.exports._createMergedStream = createMergedStream
function createMergedStream (a, b) {
linkStreams(a, b)
return sortedUnionStream(b, a, ({name}) => name)
}
// Reads the local index and returns a stream that spits out package data.
module.exports._createCacheEntryStream = createCacheEntryStream
function createCacheEntryStream (cacheFile, opts) {
log.verbose('all-package-metadata', 'creating entry stream from local cache')
log.verbose('all-package-metadata', cacheFile)
return statAsync(cacheFile).then(stat => {
// TODO - This isn't very helpful if `cacheFile` is empty or just `{}`
const entryStream = ms.pipeline.obj(
fs.createReadStream(cacheFile),
JSONStream.parse('*'),
// I believe this passthrough is necessary cause `jsonstream` returns
// weird custom streams that behave funny sometimes.
ms.through.obj()
)
return extractUpdated(entryStream, 'cached-entry-stream', opts)
})
}
// Stream of entry updates from the server. If `latest` is `0`, streams the
// entire metadata object from the registry.
module.exports._createEntryUpdateStream = createEntryUpdateStream
function createEntryUpdateStream (staleness, latest, opts) {
log.verbose('all-package-metadata', 'creating remote entry stream')
let partialUpdate = false
let uri = '/-/all'
if (latest && (Date.now() - latest < (staleness * 1000))) {
// Skip the request altogether if our `latest` isn't stale.
log.verbose('all-package-metadata', 'Local data up to date, skipping update')
return BB.resolve({})
} else if (latest === 0) {
log.warn('', 'Building the local index for the first time, please be patient')
log.verbose('all-package-metadata', 'No cached data: requesting full metadata db')
} else {
log.verbose('all-package-metadata', 'Cached data present with timestamp:', latest, 'requesting partial index update')
uri += '/since?stale=update_after&startkey=' + latest
partialUpdate = true
}
return npmFetch(uri, opts).then(res => {
log.silly('all-package-metadata', 'request stream opened, code:', res.statusCode)
let entryStream = ms.pipeline.obj(
res.body,
JSONStream.parse('*', (pkg, key) => {
if (key[0] === '_updated' || key[0][0] !== '_') {
return pkg
}
})
)
if (partialUpdate) {
// The `/all/since` endpoint doesn't return `_updated`, so we
// just use the request's own timestamp.
return {
updateStream: entryStream,
updatedLatest: Date.parse(res.headers.get('date'))
}
} else {
return extractUpdated(entryStream, 'entry-update-stream', opts)
}
})
}
// Both the (full) remote requests and the local index have `_updated` as their
// first returned entries. This is the "latest" unix timestamp for the metadata
// in question. This code does a bit of juggling with the data streams
// so that we can pretend that field doesn't exist, but still extract `latest`
function extractUpdated (entryStream, label, opts) {
log.silly('all-package-metadata', 'extracting latest')
return new BB((resolve, reject) => {
function nope (msg) {
return function () {
log.warn('all-package-metadata', label, msg)
entryStream.removeAllListeners()
entryStream.destroy()
reject(new Error(msg))
}
}
const onErr = nope('Failed to read stream')
const onEnd = nope('Empty or invalid stream')
entryStream.on('error', onErr)
entryStream.on('end', onEnd)
entryStream.once('data', latest => {
log.silly('all-package-metadata', 'got first stream entry for', label, latest)
entryStream.removeListener('error', onErr)
entryStream.removeListener('end', onEnd)
if (typeof latest === 'number') {
// The extra pipeline is to return a stream that will implicitly unpause
// after having an `.on('data')` listener attached, since using this
// `data` event broke its initial state.
resolve({
updateStream: entryStream.pipe(ms.through.obj()),
updatedLatest: latest
})
} else {
reject(new Error('expected first entry to be _updated'))
}
})
})
}
// Creates a stream that writes input metadata to the current cache.
// Cache updates are atomic, and the stream closes when *everything* is done.
// The stream is also passthrough, so entries going through it will also
// be output from it.
module.exports._createCacheWriteStream = createCacheWriteStream
function createCacheWriteStream (cacheFile, latest, opts) {
return _ensureCacheDirExists(cacheFile, opts).then(() => {
log.silly('all-package-metadata', 'creating output stream')
const outStream = _createCacheOutStream()
const cacheFileStream = writeStreamAtomic(cacheFile)
const inputStream = _createCacheInStream(
cacheFileStream, outStream, latest
)
// Glue together the various streams so they fail together.
// `cacheFileStream` errors are already handled by the `inputStream`
// pipeline
let errEmitted = false
linkStreams(inputStream, outStream, () => { errEmitted = true })
cacheFileStream.on('close', () => !errEmitted && outStream.end())
return ms.duplex.obj(inputStream, outStream)
})
}
function _ensureCacheDirExists (cacheFile, opts) {
var cacheBase = path.dirname(cacheFile)
log.silly('all-package-metadata', 'making sure cache dir exists at', cacheBase)
return correctMkdir(opts.cache).then(st => {
return mkdir(cacheBase).then(made => {
return chownr(made || cacheBase, st.uid, st.gid)
})
})
}
function _createCacheOutStream () {
// NOTE: this looks goofy, but it's necessary in order to get
// JSONStream to play nice with the rest of everything.
return ms.pipeline.obj(
ms.through(),
JSONStream.parse('*', (obj, key) => {
// This stream happens to get _updated passed through it, for
// implementation reasons. We make sure to filter it out cause
// the fact that it comes t
if (typeof obj === 'object') {
return obj
}
}),
ms.through.obj()
)
}
function _createCacheInStream (writer, outStream, latest) {
let updatedWritten = false
const inStream = ms.pipeline.obj(
ms.through.obj((pkg, enc, cb) => {
if (!updatedWritten && typeof pkg === 'number') {
// This is the `_updated` value getting sent through.
updatedWritten = true
return cb(null, ['_updated', pkg])
} else if (typeof pkg !== 'object') {
this.emit('error', new Error('invalid value written to input stream'))
} else {
// The [key, val] format is expected by `jsonstream` for object writing
cb(null, [pkg.name, pkg])
}
}),
JSONStream.stringifyObject('{', ',', '}'),
ms.through((chunk, enc, cb) => {
// This tees off the buffer data to `outStream`, and then continues
// the pipeline as usual
outStream.write(chunk, enc, () => cb(null, chunk))
}),
// And finally, we write to the cache file.
writer
)
inStream.write(latest)
return inStream
}
// Links errors between `a` and `b`, preventing cycles, and calls `cb` if
// an error happens, once per error.
function linkStreams (a, b, cb) {
var lastError = null
a.on('error', function (err) {
if (err !== lastError) {
lastError = err
b.emit('error', err)
cb && cb(err)
}
})
b.on('error', function (err) {
if (err !== lastError) {
lastError = err
a.emit('error', err)
cb && cb(err)
}
})
}