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var fs = require('fs');
function Options(defaults) {
var internalValues = {};
var values = this.value = {};
Object.keys(defaults).forEach(function(key) {
internalValues[key] = defaults[key];
Object.defineProperty(values, key, {
get: function() { return internalValues[key]; },
configurable: false,
enumerable: true
});
});
this.reset = function() {
Object.keys(defaults).forEach(function(key) {
internalValues[key] = defaults[key];
});
return this;
}
this.merge = function(options, required) {
options = options || {};
if (Object.prototype.toString.call(required) === '[object Array]') {
var missing = [];
for (var i = 0, l = required.length; i < l; ++i) {
var key = required[i];
if (typeof options[key] === 'undefined') {
missing.push(key);
}
}
if (missing.length > 0) {
if (missing.length > 1) {
throw new Error('options ' +
missing.slice(0, missing.length - 1).join(', ') + ' and ' +
missing[missing.length - 1] + ' must be defined');
}
else throw new Error('option ' + missing[0] + ' must be defined');
}
}
Object.keys(options).forEach(function(key) {
if (typeof internalValues[key] !== 'undefined') {
internalValues[key] = options[key];
}
});
return this;
}
this.copy = function(keys) {
var obj = {};
Object.keys(defaults).forEach(function(key) {
if (keys.indexOf(key) !== -1) {
obj[key] = values[key];
}
});
return obj;
}
this.read = function(filename, cb) {
if (typeof cb == 'function') {
var self = this;
fs.readFile(filename, function(error, data) {
if (error) return cb(error);
var conf = JSON.parse(data);
self.merge(conf);
cb();
});
}
else {
var conf = JSON.parse(fs.readFileSync(filename));
this.merge(conf);
}
return this;
}
Object.freeze(values);
Object.freeze(this);
}
module.exports = Options;
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I currently hold the following qualifications (amongst others, I also studied Music Technology and Electronics, for my sins)
- MSc (Passed with distinctions), in Information Technology for E-Commerce
- BSc Hons (1st class) in Computer Science & Artificial Intelligence
Both of these at Sussex University UK.
Award(s)
I am lucky enough to have won a few awards for Zany Crazy code articles over the years
- Microsoft C# MVP 2016
- Codeproject MVP 2016
- Microsoft C# MVP 2015
- Codeproject MVP 2015
- Microsoft C# MVP 2014
- Codeproject MVP 2014
- Microsoft C# MVP 2013
- Codeproject MVP 2013
- Microsoft C# MVP 2012
- Codeproject MVP 2012
- Microsoft C# MVP 2011
- Codeproject MVP 2011
- Microsoft C# MVP 2010
- Codeproject MVP 2010
- Microsoft C# MVP 2009
- Codeproject MVP 2009
- Microsoft C# MVP 2008
- Codeproject MVP 2008
- And numerous codeproject awards which you can see over at my blog