晋太元中,武陵人捕鱼为业。缘溪行,忘路之远近。忽逢桃花林,夹岸数百步,中无杂树,芳草鲜美,落英缤纷。渔人甚异之,复前行,欲穷其林。 林尽水源,便得一山,山有小口,仿佛若有光。便舍船,从口入。初极狭,才通人。复行数十步,豁然开朗。土地平旷,屋舍俨然,有良田、美池、桑竹之属。阡陌交通,鸡犬相闻。其中往来种作,男女衣着,悉如外人。黄发垂髫,并怡然自乐。 见渔人,乃大惊,问所从来。具答之。便要还家,设酒杀鸡作食。村中闻有此人,咸来问讯。自云先世避秦时乱,率妻子邑人来此绝境,不复出焉,遂与外人间隔。问今是何世,乃不知有汉,无论魏晋。此人一一为具言所闻,皆叹惋。余人各复延至其家,皆出酒食。停数日,辞去。此中人语云:“不足为外人道也。”(间隔 一作:隔绝) 既出,得其船,便扶向路,处处志之。及郡下,诣太守,说如此。太守即遣人随其往,寻向所志,遂迷,不复得路。 南阳刘子骥,高尚士也,闻之,欣然规往。未果,寻病终。后遂无问津者。
| DIR:/lib/node_modules/npm/node_modules/cacache/lib/ |
| Current File : //lib/node_modules/npm/node_modules/cacache/lib/verify.js |
'use strict'
const BB = require('bluebird')
const contentPath = require('./content/path')
const figgyPudding = require('figgy-pudding')
const finished = BB.promisify(require('mississippi').finished)
const fixOwner = require('./util/fix-owner')
const fs = require('graceful-fs')
const glob = BB.promisify(require('glob'))
const index = require('./entry-index')
const path = require('path')
const rimraf = BB.promisify(require('rimraf'))
const ssri = require('ssri')
BB.promisifyAll(fs)
const VerifyOpts = figgyPudding({
concurrency: {
default: 20
},
filter: {},
log: {
default: { silly () {} }
}
})
module.exports = verify
function verify (cache, opts) {
opts = VerifyOpts(opts)
opts.log.silly('verify', 'verifying cache at', cache)
return BB.reduce([
markStartTime,
fixPerms,
garbageCollect,
rebuildIndex,
cleanTmp,
writeVerifile,
markEndTime
], (stats, step, i) => {
const label = step.name || `step #${i}`
const start = new Date()
return BB.resolve(step(cache, opts)).then(s => {
s && Object.keys(s).forEach(k => {
stats[k] = s[k]
})
const end = new Date()
if (!stats.runTime) { stats.runTime = {} }
stats.runTime[label] = end - start
return stats
})
}, {}).tap(stats => {
stats.runTime.total = stats.endTime - stats.startTime
opts.log.silly('verify', 'verification finished for', cache, 'in', `${stats.runTime.total}ms`)
})
}
function markStartTime (cache, opts) {
return { startTime: new Date() }
}
function markEndTime (cache, opts) {
return { endTime: new Date() }
}
function fixPerms (cache, opts) {
opts.log.silly('verify', 'fixing cache permissions')
return fixOwner.mkdirfix(cache, cache).then(() => {
// TODO - fix file permissions too
return fixOwner.chownr(cache, cache)
}).then(() => null)
}
// Implements a naive mark-and-sweep tracing garbage collector.
//
// The algorithm is basically as follows:
// 1. Read (and filter) all index entries ("pointers")
// 2. Mark each integrity value as "live"
// 3. Read entire filesystem tree in `content-vX/` dir
// 4. If content is live, verify its checksum and delete it if it fails
// 5. If content is not marked as live, rimraf it.
//
function garbageCollect (cache, opts) {
opts.log.silly('verify', 'garbage collecting content')
const indexStream = index.lsStream(cache)
const liveContent = new Set()
indexStream.on('data', entry => {
if (opts.filter && !opts.filter(entry)) { return }
liveContent.add(entry.integrity.toString())
})
return finished(indexStream).then(() => {
const contentDir = contentPath._contentDir(cache)
return glob(path.join(contentDir, '**'), {
follow: false,
nodir: true,
nosort: true
}).then(files => {
return BB.resolve({
verifiedContent: 0,
reclaimedCount: 0,
reclaimedSize: 0,
badContentCount: 0,
keptSize: 0
}).tap((stats) => BB.map(files, (f) => {
const split = f.split(/[/\\]/)
const digest = split.slice(split.length - 3).join('')
const algo = split[split.length - 4]
const integrity = ssri.fromHex(digest, algo)
if (liveContent.has(integrity.toString())) {
return verifyContent(f, integrity).then(info => {
if (!info.valid) {
stats.reclaimedCount++
stats.badContentCount++
stats.reclaimedSize += info.size
} else {
stats.verifiedContent++
stats.keptSize += info.size
}
return stats
})
} else {
// No entries refer to this content. We can delete.
stats.reclaimedCount++
return fs.statAsync(f).then(s => {
return rimraf(f).then(() => {
stats.reclaimedSize += s.size
return stats
})
})
}
}, { concurrency: opts.concurrency }))
})
})
}
function verifyContent (filepath, sri) {
return fs.statAsync(filepath).then(stat => {
const contentInfo = {
size: stat.size,
valid: true
}
return ssri.checkStream(
fs.createReadStream(filepath),
sri
).catch(err => {
if (err.code !== 'EINTEGRITY') { throw err }
return rimraf(filepath).then(() => {
contentInfo.valid = false
})
}).then(() => contentInfo)
}).catch({ code: 'ENOENT' }, () => ({ size: 0, valid: false }))
}
function rebuildIndex (cache, opts) {
opts.log.silly('verify', 'rebuilding index')
return index.ls(cache).then(entries => {
const stats = {
missingContent: 0,
rejectedEntries: 0,
totalEntries: 0
}
const buckets = {}
for (let k in entries) {
if (entries.hasOwnProperty(k)) {
const hashed = index._hashKey(k)
const entry = entries[k]
const excluded = opts.filter && !opts.filter(entry)
excluded && stats.rejectedEntries++
if (buckets[hashed] && !excluded) {
buckets[hashed].push(entry)
} else if (buckets[hashed] && excluded) {
// skip
} else if (excluded) {
buckets[hashed] = []
buckets[hashed]._path = index._bucketPath(cache, k)
} else {
buckets[hashed] = [entry]
buckets[hashed]._path = index._bucketPath(cache, k)
}
}
}
return BB.map(Object.keys(buckets), key => {
return rebuildBucket(cache, buckets[key], stats, opts)
}, { concurrency: opts.concurrency }).then(() => stats)
})
}
function rebuildBucket (cache, bucket, stats, opts) {
return fs.truncateAsync(bucket._path).then(() => {
// This needs to be serialized because cacache explicitly
// lets very racy bucket conflicts clobber each other.
return BB.mapSeries(bucket, entry => {
const content = contentPath(cache, entry.integrity)
return fs.statAsync(content).then(() => {
return index.insert(cache, entry.key, entry.integrity, {
metadata: entry.metadata,
size: entry.size
}).then(() => { stats.totalEntries++ })
}).catch({ code: 'ENOENT' }, () => {
stats.rejectedEntries++
stats.missingContent++
})
})
})
}
function cleanTmp (cache, opts) {
opts.log.silly('verify', 'cleaning tmp directory')
return rimraf(path.join(cache, 'tmp'))
}
function writeVerifile (cache, opts) {
const verifile = path.join(cache, '_lastverified')
opts.log.silly('verify', 'writing verifile to ' + verifile)
try {
return fs.writeFileAsync(verifile, '' + (+(new Date())))
} finally {
fixOwner.chownr.sync(cache, verifile)
}
}
module.exports.lastRun = lastRun
function lastRun (cache) {
return fs.readFileAsync(
path.join(cache, '_lastverified'), 'utf8'
).then(data => new Date(+data))
}
|