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Strange unicode characters when reading in file in node.js app

I am attempting to write a node app that reads in a set of files, splits them into lines, and puts the lines into an array. Pretty simple. It works on quite a few files except some SQL files that I am working with. For some reason I seem to be getting some kind of unicode output when I split the lines up. The app looks something like this:

fs = require("fs");
var data = fs.readFileSync("test.sql", "utf8");
console.log(data);
lines = data.split("\n");
console.log(lines);

The input file looks something like this:

use whatever
go

The output looks like this:

��use whatever
go

[ '��u\u0000s\u0000e\u0000 \u0000w\u0000h\u0000a\u0000t\u0000e\u0000v\u0000e\u0000r\u0000',
  '\u0000g\u0000o\u0000',
  '\u0000' ]

As you can see there is some kind of unrecognized character at the beginning of the file. After reading the data in and directly outputting it, it looks okay except for this character. However, if I then attempt to split it up into lines, I get all these unicode-like characters. Basically it's all the actual characters with "\u0000" at the beginning of each one.

I have no idea what's going on here but it appears to have something to do with the characters in the file itself. If I copy and paste the text of the file into another new file and run the app on the new file, it works fine. I assume that whatever is causing this issue is being stripped out during the copy and paste process.

like image 441
d512 Avatar asked Jan 18 '13 16:01

d512


2 Answers

Your file is in UTF-16 Little Big Endian, not UTF-8.

var data = fs.readFileSync("test.sql", "utf16le"); //Not sure if this eats the BOM

Unfortunately node.js only supports UTF-16 Little Endian or UTF-16LE (Can't be sure from reading docs, there is a slight difference between them; namely that UTF-16LE does not use BOMs), so you have to use iconv or convert the file to UTF-8 some other way.

Example:

var Iconv  = require('iconv').Iconv,
    fs = require("fs");

var buffer = fs.readFileSync("test.sql"),
    iconv = new Iconv( "UTF-16", "UTF-8");

var result = iconv.convert(buffer).toString("utf8");
like image 200
Esailija Avatar answered Sep 20 '22 14:09

Esailija


Is this perhaps the BOM (Byte-Order-Mark)? Make sure you save your files without the BOM or include code to strip the BOM.

The BOM is usually invisible in text editors.

I know Notepad++ has a feature where you can easily strip a BOM from a file. Encoding > Encode in UTF-8 without BOM.

like image 39
Halcyon Avatar answered Sep 20 '22 14:09

Halcyon