SFTP utils

SFTP.js

/**
 * Get the SFTP binary based on OS
 */
var binary = function() {
    var windows =  require("os").type().match(/windows/i);
    return windows ? "psftp" : "sftp";
}

/**
 * Utility function to process SFTP commands
 * Callback function on completion gets 4 params: exit_code,exit_signal,infos, errors
 * e.g. function(exit_code,exit_signal,infos,errors)
 * The exit_code and exit_signal are the standard params returned from the node.js exit event
 * (a successful exit has a code of 0)
 * The infos and errors are just strings containing any info and error logs from the SFTP commands
 * @param server
 * @param user
 * @param password
 * @param commands
 * @param callback
 */
exports.processCommands = function processCommands(server,user,password,commands,callback) {
    var buffer_infos = '';
    var buffer_errors = '';
    var shell;
    shell = require("child_process").spawn(_binary(),[server,"-l",user,"-pw",password,"-v"]);
    commands.forEach( function(command) {
        buffer_infos += 'INFO: ' + "Executing command: " + command;
        shell.stdin.write(command + "\n");
        shell.stdin.end();
    });

    shell.stdout.on('data', function (data) {
        buffer_infos += 'INFO: ' + data;
    });

    shell.stderr.on('data', function (data) {
        buffer_errors += 'WARN: ' + data;
    });

    shell.on('exit', function(code, signal) {
        callback(code,signal,buffer_infos,buffer_errors)
    });

}

/**
 * Utility function to return stats for the specified filename
 * currently just returns file size
 * @param server
 * @param user
 * @param password
 * @param filename
 * @param dir
 */
exports.filestats = function(server,user,password,filename,dir) {
    var commands = [];
    if (dir) {
        commands.push("cd " + dir);
    }
    commands.push("dir");
    commands.push("exit");
    processCommands(server,user,password,commands,function(exit_code,exit_signal,infos,errors) {
        // get file size
        var buffer = infos.substring(0,infos.indexOf(filename));
        // then find 4 spaces - this is just before the size in the output
        var index = buffer.lastIndexOf('    ') + 4;
        buffer = buffer.substring(index);
        // find next single space this is just after the size
        buffer = buffer.substring(0,buffer.indexOf(' '));
        return {
            size: buffer
        };
    });

}