Saved Docusign Document PDF's come out corrupted - pdf

Question

I created a listener page that receives the Docusign webhooks. Everything is working as far as pulling data from the webhook, but when I cycle through the DocumentPDF's, it creates the PDF files but they are corrupted and cannot be opened (when I try to open it in Acrobat, I receive the following message: Acrobat could not open ... because it is either not a supported file type or because the file has been damaged.")
Can anybody help me figure out why the created pdf files are corrupted?
My code for the page is as follows:
protected void Page_Load(object sender, EventArgs e)
{
StreamReader sr = new StreamReader(Request.InputStream);
string xml = sr.ReadToEnd();
string fileName = HttpContext.Current.Server.MapPath("") + "\\Results\\" + DateTime.Now.Ticks + ".xml";
File.WriteAllText(fileName, xml);
try
{
XmlDocument xmldoc = new XmlDocument();
xmldoc.LoadXml(xml);
var mgr = new XmlNamespaceManager(xmldoc.NameTable);
mgr.AddNamespace("a", "http://www.docusign.net/API/3.0");
XmlNode envelopeStatus = xmldoc.SelectSingleNode("//a:EnvelopeStatus", mgr);
XmlNode envelopeId = envelopeStatus.SelectSingleNode("//a:EnvelopeID", mgr);
XmlNode status = envelopeStatus.SelectSingleNode("//a:Status", mgr);
if (status.InnerText == "Completed")
{
LogException("Looking for DocPDF's_" + DateTime.Now.Ticks + ";");
// Loop through the DocumentPDFs element, storing each document.
XmlNode docs = xmldoc.SelectSingleNode("//a:DocumentPDFs", mgr);
foreach (XmlNode doc in docs.ChildNodes)
{
string documentName = doc.ChildNodes[0].InnerText; // pdf.SelectSingleNode("//a:Name", mgr).InnerText;
string documentId = doc.ChildNodes[2].InnerText; // pdf.SelectSingleNode("//a:DocumentID", mgr).InnerText;
string byteStr = doc.ChildNodes[1].InnerText; // pdf.SelectSingleNode("//a:PDFBytes", mgr).InnerText;
LogException("Writing Out PDF_" + HttpContext.Current.Server.MapPath("") + "\\Documents\\" + envelopeId.InnerText + "_" + documentId + "_" + documentName + "_" + DateTime.Now.Ticks + ";");
File.WriteAllText(HttpContext.Current.Server.MapPath("") + "\\Documents\\" + envelopeId.InnerText + "_" + documentId + "_" + documentName, byteStr);
LogException("Successfully wrote out PDF_" + DateTime.Now.Ticks + ";");
}
}
}
catch (Exception ex)
{
LogException("Exception: " + ex.Message + "; InnerException: " + ex.InnerException.ToString() + "_" + DateTime.Now.Ticks + ";");
}
}

Answer 1

#mkl is correct. The Webhook (Connect) notification message's PDF content is base64 encoded. Decode it to obtain the PDF file.
An example: see line 402 of the recipe example webhook listener --
pdf_file.write(base64.b64decode(pdf.PDFBytes.string))

Answer 2

I am using an Azure Function and using a Blob storage to save it.
This worked for me:
var byteStr = doc.ChildNodes[1].InnerText;
outputBlob.Write(System.Convert.FromBase64String(byteStr));