@npmcorp/copy

@npminc/copy

Copy files, directories and symlinks

const copy = require('@npminc/copy')
copy('/path/to/thing', '/new/path/thing').then(() => {
  // this is now copied
}).catch(err => {
  // oh noooo
})

Copies files, directories and symlinks. Ownership is maintained when running as root, permissions are always maintained. On Windows, if symlinks are unavailable then junctions will be used.

PUBLIC INTERFACE

copy(from, to, [options]) → Promise

Recursively copies from to to and resolves its promise when finished. If to already exists then the promise will be rejected with an EEXIST error.

Options are:

• maxConcurrency – (Default: 1) The maximum number of concurrent copies to do at once.
• recurseWith - (Default: copy.item) The function to call on each file after recursing into a directory.
• isWindows - (Default: process.platform === 'win32') If true enables Windows symlink semantics. This requires an extra stat to determine if the destination of a symlink is a file or directory. If symlinking a directory fails then we'll try making a junction instead.

Options can also include dependency injection:

• Promise - (Default: global.Promise) The promise implementation to use, defaults to Node's.
• fs - (Default: require('fs')) The filesystem module to use. Can be used to use graceful-fs or to inject a mock.
• writeStreamAtomic - (Default: require('fs-write-stream-atomic')) The implementation of writeStreamAtomic to use. Used to inject a mock.
• getuid - (Default: process.getuid) A function that returns the current UID. Used to inject a mock.

EXTENSION INTERFACE

Ordinarily you'd only call copy above. But it's possible to use it's component functions directly. This is useful if, say, you're writing @npminc/move.

copy.file(from, to, options) → Promise

Copies a ordinary file from to destination to. Uses fs-write-stream-atomic to ensure that the file is entirely copied or not at all.

Options are:

• uid, gid - (Optional) If getuid() is 0 then this and gid will be used to set the user and group of to. If uid is present then gid must be too.
• mode - (Optional) If set then to will have its perms set to mode.
• fs - (Default: require('fs')) The filesystem module to use. Can be used to use graceful-fs or to inject a mock.
• Promise - (Default: global.Promise) The promise implementation to use, defaults to Node's.
• writeStreamAtomic - (Default require('fs-write-stream-atomic')) The implementation of writeStreamAtomic to use. Used to inject a mock.

copy.symlink(from, to, options) → Promise

Copies a symlink from to destination to. If on Windows then if symlinking fails, a junction will be used instead.

Options are:

• top - The top level the copy is being run from. This is used to determine if the symlink destination is within the set of files we're copying or outside it.
• fs - (Default: require('fs')) The filesystem module to use. Can be used to use graceful-fs or to inject a mock.
• Promise - (Default: global.Promise) The promise implementation to use, defaults to Node's.
• isWindows - (Default: process.platform === 'win32') If true enables Windows symlink semantics. This requires an extra stat to determine if the destination of a symlink is a file or directory. If symlinking a directory fails then we'll try making a junction instead.

copy.recurse(from, to, options) → Promise

Reads all of the files in directory from and adds them to the queue using recurseWith (by default copy.item).

Options are:

• queue - A run-queue object to add files found inside from to.
• recurseWith - (Default: copy.item) The function to call on each file after recursing into a directory.
• uid, gid - (Optional) If getuid() is 0 then this and gid will be used to set the user and group of to. If uid is present then gid must be too.
• mode - (Optional) If set then to will have its perms set to mode.
• fs - (Default: require('fs')) The filesystem module to use. Can be used to use graceful-fs or to inject a mock.
• getuid - (Default: process.getuid) A function that returns the current UID. Used to inject a mock.

copy.item(from, to, options) → Promise

Copies some kind of from to destination to. This looks at the filetype and calls copy.file, copy.symlink or copy.recurse as appropriate.

Symlink copies are queued with a priority such that they happen after all file and directory copies as you can't create a junction on windows to a file that doesn't exist yet.

Options are:

• top - The top level the copy is being run from. This is used to determine if the symlink destination is within the set of files we're copying or outside it.
• queue - The run-queue object to pass to copy.recurse if from is a directory.
• recurseWith - (Default: copy.item) The function to call on each file after recursing into a directory.
• uid, gid - (Optional) If getuid() is 0 then this and gid will be used to set the user and group of to. If uid is present then gid must be too.
• mode - (Optional) If set then to will have its perms set to mode.
• fs - (Default: require('fs')) The filesystem module to use. Can be used to use graceful-fs or to inject a mock.
• getuid - (Default: process.getuid) A function that returns the current UID. Used to inject a mock.
• isWindows - (Default: process.platform === 'win32') If true enables Windows symlink semantics. This requires an extra stat to determine if the destination of a symlink is a file or directory. If symlinking a directory fails then we'll try making a junction instead.
• Promise - (Default: global.Promise) The promise implementation to use, defaults to Node's.
• writeStreamAtomic - (Default require('fs-write-stream-atomic')) The implementation of writeStreamAtomic to use. Used to inject a mock.