node-temp -- temporary files and directories for node.js

Handles generating a unique file/directory name under the appropriate system temporary directory, changing the file to an appropriate mode, and supports automatic removal.

temp has a similar API to the fs module.

Synopsis

You can create temporary files with open and openSync, temporary directories with mkdir and mkdirSync, or you can get a unique name in the system temporary directory with path.

Working copies of the following examples can be found under the examples directory.

Temporary Files

To create a temporary file use open or openSync, passing them an optional prefix, suffix, or both (see below for details on affixes). The object passed to the callback (or returned) has path and fd keys:

{ path: "/path/to/file",
, fd: theFileDescriptor
}

In this example we write to a temporary file and call out to grep and wc -l to determine the number of time foo occurs in the text. The temporary file is chmod'd 0600 and cleaned up automatically when the process at exit:

var temp = require('temp'),
    fs   = require('fs'),
    util  = require('util'),
    exec = require('child_process').exec;

// Fake data
var myData = "foo\nbar\nfoo\nbaz";

// Process the data (note: error handling omitted)
temp.open('myprefix', function(err, info) {
  fs.write(info.fd, myData);
  fs.close(info.fd, function(err) {
    exec("grep foo '" + info.path + "' | wc -l", function(err, stdout) {
      util.puts(stdout.trim());
    });
  });
});

Temporary Directories

To create a temporary directory, use mkdir or mkdirSync, passing it an optional prefix, suffix, or both (see below for details on affixes).

In this example we create a temporary directory, write to a file within it, call out to an external program to create a PDF, and read the result. While the external process creates a lot of additional files, the temporary directory is removed automatically at exit:

var temp = require('../lib/temp'),
    fs   = require('fs'),
    util = require('util'),
    path = require('path'),
    exec = require('child_process').exec;

// For use with ConTeXt, http://wiki.contextgarden.net
var myData = "\\starttext\nHello World\n\\stoptext";

temp.mkdir('pdfcreator', function(err, dirPath) {
  var inputPath = path.join(dirPath, 'input.tex')
  fs.writeFile(inputPath, myData, function(err) {
    if (err) throw err;
    process.chdir(dirPath);
    exec("texexec '" + inputPath + "'", function(err) {
      if (err) throw err;
      fs.readFile(path.join(dirPath, 'input.pdf'), function(err, data) {
        if (err) throw err;
        sys.print(data);
      });
    });
  });
});

Temporary Streams

To create a temporary WriteStream, use 'createWriteStream', which sits on top of fs.createWriteStream. The return value is a fs.WriteStream whose path is registered for removal when temp.cleanup is called.

var temp = require('temp');

var stream = temp.createWriteStream();
stream.write("Some data");
// Maybe do some other things
stream.end();

Affixes

You can provide custom prefixes and suffixes when creating temporary files and directories. If you provide a string, it is used as the prefix for the temporary name. If you provide an object with prefix and suffix keys, they are used for the temporary name.

Here are some examples:

"aprefix": A simple prefix, prepended to the filename; this is shorthand for:
{prefix: "aprefix"}: A simple prefix, prepended to the filename
{suffix: ".asuffix"}: A suffix, appended to the filename (especially useful when the file needs to be named with specific extension for use with an external program).
{prefix: "myprefix", suffix: "mysuffix"}: Customize both affixes
null: Use the defaults for files and directories (prefixes "f-" and "d-", respectively, no suffixes).

In this simple example we read a pdf, write it to a temporary file with a .pdf extension, and close it.

var fs   = require('fs'),
    temp = require('temp');

fs.readFile('/path/to/source.pdf', function(err, data) {
  temp.open({suffix: '.pdf'}, function(err, info) {
    if (err) throw err;
    fs.write(info.fd, contents);
    fs.close(info.fd, function(err) {
      if (err) throw err;
      // Do something with the file
    });
  });
});

Just a path, please

If you just want a unique name in your temporary directory, use path:

var fs = require('fs');
var tempName = temp.path({suffix: '.pdf'});
// Do something with tempName

Note: The file isn't created for you, and the mode is not changed -- and it will not be removed automatically at exit. If you use path, it's all up to you.

Compatibility

Works with Node.js v0.6.0 on OS X. Please let me know if you have problems running it on a later version of Node.js or have platform problems.

Installation

Install it using npm:

$ npm install temp

Or get it directly from: http://github.com/bruce/node-temp

Testing

For now, run test/test-temp.js:

$ node test/test-temp.js

Contributing

You can find the repository at: http://github.com/bruce/node-temp

Issues/Feature Requests can be submitted at: http://github.com/bruce/node-temp/issues

I'd really like to hear your feedback, and I'd love to receive your pull-requests!

haklop / node-temp