combiner

combiner is both a command-line utility and a library for merging and processing files. The basic idea behind its is to take advantage of a functional, flexible middleware that composes map/reduce/filter callbacks.

Install

From NPM: $ npm install combiner

From Source Code: $ git clone https://github.com/azer/combiner.git $ cd combiner; $ make deps $ make install

Quick Start

Besides of the API provided by the library, combiner includes a command line script to accomplish composite file merging aims.

Most basic usage example is running it without any parameters. Which produces a merge of all files on the executed directory.

$ echo "foo">a;
$ echo "bar">b;
$ echo "qux">c;
$ combiner
foo
bar
qux

Specific filenames and directories can be picked as well.

$ combiner a c
foo
qux

The goal of combiner is to provide a middleware that lets us to process these files easily;

$ combiner -map "function(el,callback){ callback(null, el.toUpperCase()) }"
FOO
BAR
QUX

The simple command above uppercases all combinerd contents, as you've supposed. The other options available are reduce and filter. Reduce option basicly replaces the default function joining the contens of the files;

$ combiner -reduce "function(a,b,callback){ callback(null,a+","+b) }"
FOO,BAR,QUX

It's quite similar with the map function as you've seen above. Unlike the map and reduce options, filter callbacks take filenames instead of the contents of the files.

$ combiner -filter "function(filename, cb){ cb(null,/^f|q/); }"
FOO
QUX

The reasion behind this approach lies on the basic design idea of the combiner library. Its body is made up of a chain of functions, applying listed operations below;

• find all files in the working directory
• include and flatten nested directories if any exists
• apply filter callbacks to gathered filenames
• apply map callbacks to the gathered filenames*
• apply specified reduce function or the default one joining passed contents with new lines.

Dependencies

• nodejs
• functools

Development

status: under development todo:

• usage example
• extend documentation (using ronn)
• build a website (combiner.kodfabrik.com)