I wrote a Python script today to mass-mail files to our clients. Our wonderful ERP system screwed up again, leaving us with PDFs of the information we needed to send out, the filenames being prefixed with a unique ID per-recipient. Rather than re-generate all documents and have them sent out properly (which likely wouldn’t have happened due to bugs in the system from a recent upgrade) we wrote this script to mail out the documents we already had. We created a CSV file with two columns: column one has the unique filename prefix, column two has the corresponding recipient’s email address.
import csv import os import smtplib import mimetypes from email.mime.multipart import MIMEMultipart from email import encoders from email.message import Message from email.mime.audio import MIMEAudio from email.mime.base import MIMEBase from email.mime.image import MIMEImage from email.mime.text import MIMEText def readCSV(): clientCSVList =  try: #set below to the CSV file you want to read. Two columns: #1 - file prefix to search #2 - email address to send file to with open("csvFile", 'rb') as csvfile: clientReader = csv.reader(csvfile, delimiter=',') missing = 0 for clientNum, email in clientReader: found = False for file in os.listdir("folder_with_files"): if file.startswith(clientNum): clientCSVList.append([clientNum, email, file]) found = True continue if found == False: missing += 1 print clientNum + " " + email print clientCSVList print "Missing: " + str(missing) except Exception as e: print "Exception: " + str(e.args) try: for client in clientCSVList: send_email("email@example.com", client, "Email Subject Here", "This text is supposed to be the body, but doesn't seem to appear", client) print client + " Success" except Exception as e: print "Exception: " + str(e.args) print client + " Failure" def send_email(sender, receiver, subject, message, fileattachment=None): emailfrom = sender emailto = receiver fileToSend = fileattachment username = "smtp_username" password = "smtp_password" msg = MIMEMultipart() msg["From"] = emailfrom msg["To"] = emailto msg["Subject"] = subject msg["Message"] = message msg.preamble = message ctype, encoding = mimetypes.guess_type(fileToSend) if ctype is None or encoding is not None: ctype = "application/octet-stream" maintype, subtype = ctype.split("/", 1) if maintype == "text": fp = open(fileToSend) # Note: we should handle calculating the charset attachment = MIMEText(fp.read(), _subtype=subtype) fp.close() elif maintype == "image": fp = open(fileToSend, "rb") attachment = MIMEImage(fp.read(), _subtype=subtype) fp.close() elif maintype == "audio": fp = open(fileToSend, "rb") attachment = MIMEAudio(fp.read(), _subtype=subtype) fp.close() else: fp = open(fileToSend, "rb") attachment = MIMEBase(maintype, subtype) attachment.set_payload(fp.read()) fp.close() encoders.encode_base64(attachment) attachment.add_header("Content-Disposition", "attachment", filename=fileToSend) msg.attach(attachment) server = smtplib.SMTP("server:25") #insert SMTP server:port in quotes server.starttls() server.login(username,password) server.sendmail(emailfrom, emailto, msg.as_string()) server.quit() def main(): readCSV() if __name__ == "__main__": main()