Node base64 encode doesn't give whole string

Good day,

I am having a weird issue with Node, I am encoding a file as Base64 and albeit it works for most of my PDFs that I am encoding, one in particular doesn't output the whole base64 string.

The actual b64 string starts like this: "JVBERi0xLjMKJf////8KNiAwIG9i..." but I only get "JVBERi0xLjMK"

Here is my code:

function sendPDF() {
    // Grab the final PDF
    require('fs').readFile(transaction.deliverable, function (err, data) {
        if (err) {
            console.log(err);
            log(2, "Couldn't read: " + transaction.deliverable);
        } else {
            transaction.deliverable = new Buffer(data, 'binary').toString('base64');
            //transaction.deliverable = data.toString('base64');
            console.log(transaction.deliverable);

}

The commented out line was another attempt. The transaction structure is:

function Transaction(snapshot) {
    var data         = snapshot.val();
    this.tid         = snapshot.key();
    this.request     = data.request;
    this.pages       = [];
    this.fileCount   = 0;
    this.deliverable = null;
    this.fileName    = "";
}

This transaction simple stores some information that I pull from Firebase however the important var, .deliverable is a string to the path of the PDF I need to encode and send.

I don't get any read errors when this happens, and the next transaction goes through this code block just fine, giving a full base64 string.

I was curious if my toString() was interpolating the base64 string, but then I thought I would have had larger problems earlier.

Any ideas? I can put this on hold and move on with my work but I would love to fix this.. Thank you.