I'm building a node js app(for learning) where i'm logging each operation into a file called log.txt
The logger module has the following code :
var fs = require('fs');
function write(data,filename)
{
  var entry = 'Time: '+new Date();
  if(filename !=null || filename != undefined) entry = entry+'\n\tFile: '+filename;
  if(data !=null || data != undefined) entry = entry+'\n\tMessage: '+data;
  entry = entry+'\n';
  fs.appendFile('./log.txt',entry,function(err){
      if(err){console.log('Log NOT Appended with data:\n\t'+entry);}
      else{console.log('Log Appended with data:\n\t'+entry);}
  });
}
exports.write = write;
now in my app.js i'm requiring it as :
var logger = require('./logger');
var fs = require('fs');
function ReadFile()
{
  var data = fs.readFileSync('./config.txt');
  if(data==null) 
          logger.write("Config data not found");
  else
      logger.write(data,"app.js");
}
ReadFile();
This throws me back an error saying :
 Object #<Object> has no method 'appendFile'
However this worked fine earlier on a different pc, I noticed this when tried to run my app on my system.
 
    