git store object

git-store.js

var zlib = require('zlib');
var crypto = require('crypto');
var shasum = crypto.createHash('sha1');
var fs = require('fs');
var path = require('path');

var content = 'what is up, doc?';
var header = 'blob ' + content.length + '\0';
var store = header + content;

// 创建所有目录
var mkdirs = module.exports.mkdirs = function(dirpath, mode, callback) {
    fs.exists(dirpath, function(exists) {
        if(exists) {
            callback(dirpath);
        } else {
            //尝试创建父目录，然后再创建当前目录
            mkdirs(path.dirname(dirpath), mode, function(){
                    fs.mkdir(dirpath, mode, callback);
            });
        }
    });
};

// SHA-1 
shasum.update(store);
var sha1 = shasum.digest('hex');

// 压缩存储
zlib.deflate(store, function (err, buffer) {
    if (!err) {
        var p = '.git/objects/' + sha1.substr(0, 2) + '/' + sha1.substr(2, 38);
        var dir = path.dirname(p);
        mkdirs(dir, '0777', function() {
            fs.writeFile(p, buffer, function(err) {
                if (err) throw err;
                console.log('saved success');
            });            
        });
    }
});