web-template-file-tree/lib/template-file.js

Utility to index files in a directory based on relative path and cache contents

var fs = require('fs');
var _ = require('underscore');
var mkdirp = require('mkdirp');
var Path = require('path');

function TemplateFile(path) {
	if (!path) {
		throw new Error('TemplateFile constructor missing required path argument');
	}
	this.path = path;
}

_.extend(TemplateFile, {
	loadAll: loadAll,
	checkAll: checkAll,
	saveAll: saveAll,
	removeAll: removeAll
});

function loadAll(files, cb) {
	eachAsync(files, function (file, cb) {
		file.load(cb);
	}, cb);
}

function checkAll(files, cb) {
	var inaccessibleFiles = [];
	eachAsync(files, function (file, cb) {
		fs.access(file.path, fs.R_OK, function (err) {
			if (err) {
				inaccessibleFiles.push(file);
			}
			cb();
		});
	}, function (err) {
		cb(null, inaccessibleFiles);
	});
}

function saveAll(files, cb) {
	eachAsync(files, function (file, cb) {
		file.save(cb);
	}, cb);
}

function removeAll(files, cb) {
	eachAsync(files, function (file, cb) {
		fs.unlink(file.path, cb);
	}, cb);
}

function eachAsync(list, iter, cb) {
	var error, n = list.length;
	if (n === 0) {
		cb();
	}
	else {
		_.each(list, function (item) {
			iter(item, function (err) {
				if (!error) {
					if (err) {
						error = err;
						cb(err);
					}
					else {
						n--;
						if (n === 0) {
							cb();
						}
					}
				}
			});
		})
	}
}

_.extend(TemplateFile.prototype, {
	load: load,
	readFile: readFile,
	save: save
});

function load(cb) {
	fs.stat(this.path, function (err, stats) {
		if (err) {
			cb(err);
		} else {
			if (!this.mtime || stats.mtime.getTime() > this.mtime.getTime()) {
				// time to load or reload
				this.mtime = stats.mtime;
				this.readFile(cb);
			} else {
				// content is up to date
				cb(null);
			}
		}
	}.bind(this));
}

function readFile(cb) {
	fs.readFile(this.path, {
		encoding: 'utf8'
	}, function (err, data) {
		if (err) {
			cb(err);
		} else {
			this.content = data;
			cb(null);
		}
	}.bind(this));
}

function save(cb) {
	mkdirp(Path.dirname(this.path), function (err) {
		if (err) {
			cb(err);
		}
		else {
			fs.writeFile(this.path, this.content, {
				encoding: 'utf8'
			}, function (err) {
				cb(err);
			});
		}
	}.bind(this));
}

module.exports = TemplateFile;