Question

In Node.js, I’m using the code below to download the file from the server. The API call is success. After I save the ‘data’ to the local file with the ‘binary’ encoding, the local file can’t be opened by the corresponding software. I compared the file size of the local file and the server file. There is a minor difference.

I can’t find where I’m wrong. Does the OAuth library supports the file download?

var OAuth = require('oauth').OAuth;

var consumer = new OAuth('',
            null,
            consumer_key, consumer_key_secret, '1.0',
            null, 'HMAC-SHA1');

consumer.get(url
        , oauth_token, ooauth_token_secret
        , function (err, data, response){
            var filename = path.join(__dirname, "test.dwg");
            var file = fs.createWriteStream(filename);

            console.log('Data length: ' + data.length);

            file.write(data, 'binary', function(err){                       
                console.log('Complete');
            });             
        }       
    );

Answer 1

I got the solution after some testing.

The reason of this issue is we are receiving the http body in ‘utf8’ encoding. Use the ‘binary’ encoding can fix it.

The oauth module only supports the utf8 encoding when get the response. This is hard code in file “oatuh\lib\oauth.js” at “Line # 375, response.setEncoding(‘utf8’);”.

Even though I set the encoding as the code below. It still doesn’t work. So this module can’t be used to download binary files.

var consumer = new OAuth('',
            null,
            consumer_key, consumer_secret, '1.0',
            null, 'HMAC-SHA1', 32, {encoding: "binary"});

Solution: Use the request module to download the file. The code is as below.

var oauth = {
    consumer_key: consumer_key
    , consumer_secret: consumer_secret
    , token: token
    , token_secret: token_secret
};
request.get({url:url, oauth:oauth, encoding: "binary"}, function(err, res, body){..});