Compound File Binary File Format extractor
npm install @albanm/cfbPure JS implementation of various container file formats, including ZIP and CFB.
In the browser:
``html`
With npm:
`bash`
$ npm install cfb
The xlscfb.js file is designed to be embedded in js-xlsx
In node:
`js`
var CFB = require('cfb');
For example, to get the Workbook content from an Excel 2003 XLS file:
`js`
var cfb = CFB.read(filename, {type: 'file'});
var workbook = CFB.find(cfb, 'Workbook');
var data = workbook.content;
It is preferable to install the library globally with npm:
`bash`
$ npm install -g cfb
The global installation adds a command cfb which can work with files:
- cfb file [names...] extracts the contents of the file. If additional names
are supplied, only the listed files will be extracted.
- cfb -l file lists the contained files (following unzip -l "short format")
- cfb -r file attempts to repair by reading and re-writing the file.
This fixes some issues with files generated by non-standard tools.
- cfb -c file [files...] creates a new file containing the listed files.Root Entry
The default root entry name is .
- cfb -a file [files...] adds the listed files to the original file.
- cfb -d file [files...] deletes the listed files from the original file.
TypeScript definitions are maintained in types/index.d.ts.
The CFB object exposes the following methods and properties:
CFB.parse(blob) takes a nodejs Buffer or an array of bytes and returns an
parsed representation of the data.
CFB.read(blob, opts) wraps parse.
CFB.find(cfb, path) performs a case-insensitive match for the path (or file
name, if there are no slashes) and returns an entry object or null if not found.
CFB.write(cfb, opts) generates a file based on the container.
CFB.writeFile(cfb, filename, opts) creates a file with the specified name.
CFB.read takes an options argument. opts.type controls the behavior:
| type | expected input |"base64"
|------------|:----------------------------------------------------------------|
| | string: Base64 encoding of the file |"binary"
| | string: binary string (byte n is data.charCodeAt(n)) |"file"
| | string: path of file that will be read (nodejs only) |n
| (default) | buffer or array of 8-bit unsigned int (byte is data[n]) |
CFB.write and CFB.writeFile take options argument.
opts.type controls the behavior:
| type | output |"base64"
|------------|:----------------------------------------------------------------|
| | string: Base64 encoding of the file |"binary"
| | string: binary string (byte n is data.charCodeAt(n)) |"file"
| | string: path of file that will be created (nodejs only) |
| (default) | buffer if available, array of 8-bit unsigned int otherwise |
opts.fileType controls the output file type:
| fileType | output |'cfb'
|:-------------------|:--------------|
| (default) | CFB container |'zip'
| | ZIP file |
opts.compression enables DEFLATE compression for ZIP file type.
The utility functions are available in the CFB.utils object. Functions thatname
accept a argument strictly deal with absolute file names:
- .cfb_new(?opts) creates a new container object..cfb_add(cfb, name, ?content, ?opts)
- adds a new file to the cfb.{unsafe:true}
Set the option to skip existence checks (for bulk additions).cfb_del(cfb, name)
- deletes the specified file.cfb_mov(cfb, old_name, new_name)
- moves the old file to new path and name.use_zlib(require("zlib"))
- loads a nodejs zlib instance.
By default, the library uses a pure JS inflate/deflate implementation. NodeJS
zlib.InflateRaw exposes the number of bytes read in versions after 8.11.0.zlib
If a supplied does not support the required features, a warning will be
displayed in the console and the pure JS fallback will be used.
The objects returned by parse and read have the following properties:
- .FullPaths is an array of the names of all of the streams (files) and
storages (directories) in the container. The paths are properly prefixed from
the root entry (so the entries are unique)
- .FileIndex is an array, in the same order as .FullPaths, whose values are
objects following the schema:
`typescript`
interface CFBEntry {
name: string; /* Case-sensitive internal name /
type: number; /* 1 = dir, 2 = file, 5 = root ; see [MS-CFB] 2.6.1 /
content: Buffer | number[] | Uint8Array; /* Raw Content /
ct?: Date; /* Creation Time /
mt?: Date; /* Modification Time /
}
Please consult the attached LICENSE file for details. All rights not explicitly
granted by the Apache 2.0 License are reserved by the Original Author.
- [MS-CFB]: Compound File Binary File Format
- ZIP APPNOTE.TXT`: https://pkware.cachefly.net/webdocs/APPNOTE/APPNOTE-6.3.4.TXT
- RFC1951: https://www.ietf.org/rfc/rfc1951.txt