npmpacote
Fetches package manifests and tarballs from the npm registry.
USAGE
const pacote = require('pacote')
// get a package manifest
pacote.manifest('foo@1.x').then(manifest => console.log('got it', manifest))
// extract a package into a folder
pacote.extract('github:npm/cli', 'some/path', options)
.then(({from, resolved, integrity}) => {
console.log('extracted!', from, resolved, integrity)
})
pacote.tarball('https://server.com/package.tgz').then(data => {
console.log('got ' + data.length + ' bytes of tarball data')
})
pacote works with any kind of package specifier that npm can install. If
you can pass it to the npm CLI, you can pass it to pacote. (In fact, that's
exactly what the npm CLI does.)
Anything that you can do with one kind of package, you can do with another.
Data that isn't relevant (like a packument for a tarball) will be simulated.
prepare scripts will be run when generating tarballs from git and
directory locations, to simulate what would be published to the
registry, so that you get a working package instead of just raw source
code that might need to be transpiled.
CLI
This module exports a command line interface that can do most of what is
described below. Run pacote -h to learn more.
Pacote - The JavaScript Package Handler, v10.1.1
Usage:
pacote resolve <spec>
Resolve a specifier and output the fully resolved target
Returns integrity and from if '--long' flag is set.
pacote manifest <spec>
Fetch a manifest and print to stdout
pacote packument <spec>
Fetch a full packument and print to stdout
pacote tarball <spec> [<filename>]
Fetch a package tarball and save to <filename>
If <filename> is missing or '-', the tarball will be streamed to stdout.
pacote extract <spec> <folder>
Extract a package to the destination folder.
Configuration values all match the names of configs passed to npm, or
options passed to Pacote. Additional flags for this executable:
--long Print an object from 'resolve', including integrity and spec.
--json Print result objects as JSON rather than node's default.
(This is the default if stdout is not a TTY.)
--help -h Print this helpful text.
For example '--cache=/path/to/folder' will use that folder as the cache.
API
The spec refers to any kind of package specifier that npm can install.
If you can pass it to the npm CLI, you can pass it to pacote. (In fact,
that's exactly what the npm CLI does.)
See below for valid opts values.
pacote.resolve(spec, opts)Resolve a specifier likefoo@latestorgithub:user/projectall the way to a tarball url, tarball file, or git repo with commit hash.pacote.extract(spec, dest, opts)Extract a package's tarball into a destination folder. Returns a promise that resolves to the{from,resolved,integrity}of the extracted package.pacote.manifest(spec, opts)Fetch (or simulate) a package's manifest (basically, thepackage.jsonfile, plus a bit of metadata). See below for more on manifests and packuments. Returns a Promise that resolves to the manifest object.pacote.packument(spec, opts)Fetch (or simulate) a package's packument (basically, the top-level package document listing all the manifests that the registry returns). See below for more on manifests and packuments. Returns a Promise that resolves to the packument object.pacote.tarball(spec, opts)Get a package tarball data as a buffer in memory. Returns a Promise that resolves to the tarball data Buffer, withfrom,resolved, andintegrityfields attached.pacote.tarball.file(spec, dest, opts)Save a package tarball data to a file on disk. Returns a Promise that resolves to{from,integrity,resolved}of the fetched tarball.pacote.tarball.stream(spec, streamHandler, opts)Fetch a tarball and make the stream available to thestreamHandlerfunction.This is mostly an internal function, but it is exposed because it does provide some functionality that may be difficult to achieve otherwise.
The
streamHandlerfunction MUST return a Promise that resolves when the stream (and all associated work) is ended, or rejects if the stream has an error.The
streamHandlerfunction MAY be called multiple times, as Pacote retries requests in some scenarios, such as cache corruption or retriable network failures.
Options
Options are passed to
npm-registry-fetch and
cacache, so in addition to these, anything for
those modules can be given to pacote as well.
Options object is cloned, and mutated along the way to add integrity, resolved, and other properties, as they are determined.
cacheWhere to store cache entries and temp files. Passed tocacache. Defaults to the same cache directory that npm will use by default, based on platform and environment.whereBase folder for resolving relativefile:dependencies.resolvedShortcut for looking up resolved values. Should be specified if known.integrityExpected integrity of fetched package tarball. If specified, tarballs with mismatched integrity values will raise anEINTEGRITYerror.umaskPermission mode mask for extracted files and directories. Defaults to0o22. See "Extracted File Modes" below.fmodeMinimum permission mode for extracted files. Defaults to0o666. See "Extracted File Modes" below.dmodeMinimum permission mode for extracted directories. Defaults to0o777. See "Extracted File Modes" below.preferOnlinePrefer to revalidate cache entries, even when it would not be strictly necessary. Defaultfalse.beforeWhen picking a manifest from a packument, only consider packages published before the specified date. Defaultnull.defaultTagThe defaultdist-tagto use when choosing a manifest from a packument. Defaults tolatest.registryThe npm registry to use by default. Defaults tohttps://registry.npmjs.org/.fullMetadataFetch the full metadata from the registry for packuments, including information not strictly required for installation (author, description, etc.) Defaults totruewhenbeforeis set, since the version publish time is part of the extended packument metadata.fullReadJsonUse the slowerread-package-jsonpackage insted ofread-package-json-fastin order to include extra fields like "readme" in the manifest. Defaults tofalse.packumentCacheFor registry packuments only, you may provide aMapobject which will be used to cache packument requests between pacote calls. This allows you to easily avoid hitting the registry multiple times (even just to validate the cache) for a given packument, since it is unlikely to change in the span of a single command.verifySignaturesA boolean that will make pacote verify the integrity signature of a manifest, if present. There must be a configured_keysentry in the config that is scoped to the registry the manifest is being fetched from.verifyAttestationsA boolean that will make pacote verify Sigstore attestations, if present. There must be a configured_keysentry in the config that is scoped to the registry the manifest is being fetched from.tufCacheWhere to store metadata/target files when retrieving the package attestation key material via TUF. Defaults to the same cache directory that npm will use by default, based on platform and environment.
Advanced API
Each different type of fetcher is exposed for more advanced usage such as using helper methods from this classes:
DirFetcherFileFetcherGitFetcherRegistryFetcherRemoteFetcher
Extracted File Modes
Files are extracted with a mode matching the following formula:
( (tarball entry mode value) | (minimum mode option) ) ~ (umask)
This is in order to prevent unreadable files or unlistable directories from
cluttering a project's node_modules folder, even if the package tarball
specifies that the file should be inaccessible.
It also prevents files from being group- or world-writable without explicit
opt-in by the user, because all file and directory modes are masked against
the umask value.
So, a file which is 0o771 in the tarball, using the default fmode of
0o666 and umask of 0o22, will result in a file mode of 0o755:
(0o771 | 0o666) => 0o777
(0o777 ~ 0o22) => 0o755
In almost every case, the defaults are appropriate. To respect exactly
what is in the package tarball (even if this makes an unusable system), set
both dmode and fmode options to 0. Otherwise, the umask config
should be used in most cases where file mode modifications are required,
and this functions more or less the same as the umask value in most Unix
systems.
Extracted File Ownership
When running as root on Unix systems, all extracted files and folders
will have their owning uid and gid values set to match the ownership
of the containing folder.
This prevents root-owned files showing up in a project's node_modules
folder when a user runs sudo npm install.
Manifests
A manifest is similar to a package.json file. However, it has a few
pieces of extra metadata, and sometimes lacks metadata that is inessential
to package installation.
In addition to the common package.json fields, manifests include:
manifest._resolvedThe tarball url or file path where the package artifact can be found.manifest._fromA normalized form of the spec passed in as an argument.manifest._integrityThe integrity value for the package artifact.manifest._idThe canonical spec of this package version: name@version.manifest.distRegistry manifests (those included in a packument) have adistobject. Onlytarballis required, though at least one ofshasumorintegrityis almost always present.tarballThe url to the associated package artifact. (Copied by Pacote tomanifest._resolved.)integrityThe integrity SRI string for the artifact. This may not be present for older packages on the npm registry. (Copied by Pacote tomanifest._integrity.)shasumLegacy integrity value. Hexadecimal-encoded sha1 hash. (Converted to an SRI string and copied by Pacote tomanifest._integritywhendist.integrityis not present.)fileCountNumber of files in the tarball.unpackedSizeSize on disk of the package when unpacked.signaturesSignatures of the shasum. Includes the keyid that correlates to akey from the npm registry
Packuments
A packument is the top-level package document that lists the set of manifests for available versions for a package.
When a packument is fetched with accept:
application/vnd.npm.install-v1+json in the HTTP headers, only the most
minimum necessary metadata is returned. Additional metadata is returned
when fetched with only accept: application/json.
For Pacote's purposes, the following fields are relevant:
versionsAn object where each key is a version, and each value is the manifest for that version.dist-tagsAn object mapping dist-tags to version numbers. This is howfoo@latestgets turned intofoo@1.2.3.timeIn the full packument, an object mapping version numbers to publication times, for theopts.beforefunctionality.
Pacote adds the following field, regardless of the accept header:
_contentLengthThe size of the packument.