How to send an email containing greek characters using rJython? - r

Question

The following function (found here) works well for messages containing ASCII characters. Can you help me modify it for multilingual messages too, because I don't know python at all?
send.email <- function(to, from, subject,
message, attachment=NULL,
username, password,
server="xxx.xxx.xxx.xxx",
confirmBeforeSend=FALSE){
# to: a list object of length 1. Using list("Recipient" = "recip#somewhere.net") will send the message to the address but
# the name will appear instead of the address.
# from: a list object of length 1. Same behavior as 'to'
# subject: Character(1) giving the subject line.
# message: Character(1) giving the body of the message
# attachment: Character(1) giving the location of the attachment
# username: character(1) giving the username. If missing and you are using Windows, R will prompt you for the username.
# password: character(1) giving the password. If missing and you are using Windows, R will prompt you for the password.
# server: character(1) giving the smtp server.
# confirmBeforeSend: Logical. If True, a dialog box appears seeking confirmation before sending the e-mail. This is to
# prevent me to send multiple updates to a collaborator while I am working interactively.
if (!is.list(to) | !is.list(from)) stop("'to' and 'from' must be lists")
if (length(from) > 1) stop("'from' must have length 1")
if (length(to) > 1) stop("'send.email' currently only supports one recipient e-mail address")
if (length(attachment) > 1) stop("'send.email' can currently send only one attachment")
if (length(message) > 1){
stop("'message' must be of length 1")
message <- paste(message, collapse="\\n\\n")
}
if (is.null(names(to))) names(to) <- to
if (is.null(names(from))) names(from) <- from
if (!is.null(attachment)) if (!file.exists(attachment)) stop(paste("'", attachment, "' does not exist!", sep=""))
if (missing(username)) username <- winDialogString("Please enter your e-mail username", "")
if (missing(password)) password <- winDialogString("Please enter your e-mail password", "")
require(rJython)
rJython <- rJython()
rJython$exec("import smtplib")
rJython$exec("import os")
rJython$exec("from email.MIMEMultipart import MIMEMultipart")
rJython$exec("from email.MIMEBase import MIMEBase")
rJython$exec("from email.MIMEText import MIMEText")
rJython$exec("from email.Utils import COMMASPACE, formatdate")
rJython$exec("from email import Encoders")
rJython$exec("import email.utils")
mail<-c(
#Email settings
paste("fromaddr = '", from, "'", sep=""),
paste("toaddrs = '", to, "'", sep=""),
"msg = MIMEMultipart()",
paste("msg.attach(MIMEText('", message, "'))", sep=""),
paste("msg['From'] = email.utils.formataddr(('", names(from), "', fromaddr))", sep=""),
paste("msg['To'] = email.utils.formataddr(('", names(to), "', toaddrs))", sep=""),
paste("msg['Subject'] = '", subject, "'", sep=""))
if (!is.null(attachment)){
mail <- c(mail,
paste("f = '", attachment, "'", sep=""),
"part=MIMEBase('application', 'octet-stream')",
"part.set_payload(open(f, 'rb').read())",
"Encoders.encode_base64(part)",
"part.add_header('Content-Disposition', 'attachment; filename=\"%s\"' % os.path.basename(f))",
"msg.attach(part)")
}
#SMTP server credentials
mail <- c(mail,
paste("username = '", username, "'", sep=""),
paste("password = '", password, "'", sep=""),
#Set SMTP server and send email, e.g., google mail SMTP server
paste("server = smtplib.SMTP('", server, "')", sep=""),
"server.ehlo()",
"server.starttls()",
"server.ehlo()",
"server.login(username,password)",
"server.sendmail(fromaddr, toaddrs, msg.as_string())",
"server.quit()")
message.details <-
paste("To: ", names(to), " (", unlist(to), ")", "\n",
"From: ", names(from), " (", unlist(from), ")", "\n",
"Using server: ", server, "\n",
"Subject: ", subject, "\n",
"With Attachments: ", attachment, "\n",
"And the message:\n", message, "\n", sep="")
if (confirmBeforeSend)
SEND <- winDialog("yesnocancel", paste("Are you sure you want to send this e-mail to ", unlist(to), "?", sep=""))
else SEND <- "YES"
if (SEND %in% "YES"){
jython.exec(rJython,mail)
cat(message.details)
}
else cat("E-mail Delivery was Canceled by the User")
}
I call it like this:
send.email(list("somebody#somecompany.com"),
list("rJythonMail#mycompany.com"),
"Δοκιμή αποστολής email με attachment",
"Με χρήση της rJython",
attachment="monthly_report.xls",
username="gd047",password="xxxxxx")

Answer 1

The issue is how your enclosed Python code is structured. This blog entry goes into more detail on how to properly send Unicode email, which you're using Python to manage the underling SMTP connection for. Note that according to R. David Murray, this will be fixed in later iterations of the email package in Python.
Here's the salient Python code you can retrofit into your calls in rJython, borrowing directly from the aforementioned blog post:
from smtplib import SMTP
from email.MIMEText import MIMEText
from email.Header import Header
from email.Utils import parseaddr, formataddr
def send_email(sender, recipient, subject, body):
"""Send an email.
All arguments should be Unicode strings (plain ASCII works as well).
Only the real name part of sender and recipient addresses may contain
non-ASCII characters.
The email will be properly MIME encoded and delivered though SMTP to
localhost port 25. This is easy to change if you want something different.
The charset of the email will be the first one out of US-ASCII, ISO-8859-1
and UTF-8 that can represent all the characters occurring in the email.
"""
# Header class is smart enough to try US-ASCII, then the charset we
# provide, then fall back to UTF-8.
header_charset = 'ISO-8859-1'
# We must choose the body charset manually
for body_charset in 'US-ASCII', 'ISO-8859-1', 'UTF-8':
try:
body.encode(body_charset)
except UnicodeError:
pass
else:
break
# Split real name (which is optional) and email address parts
sender_name, sender_addr = parseaddr(sender)
recipient_name, recipient_addr = parseaddr(recipient)
# We must always pass Unicode strings to Header, otherwise it will
# use RFC 2047 encoding even on plain ASCII strings.
sender_name = str(Header(unicode(sender_name), header_charset))
recipient_name = str(Header(unicode(recipient_name), header_charset))
# Make sure email addresses do not contain non-ASCII characters
sender_addr = sender_addr.encode('ascii')
recipient_addr = recipient_addr.encode('ascii')
# Create the message ('plain' stands for Content-Type: text/plain)
msg = MIMEText(body.encode(body_charset), 'plain', body_charset)
msg['From'] = formataddr((sender_name, sender_addr))
msg['To'] = formataddr((recipient_name, recipient_addr))
msg['Subject'] = Header(unicode(subject), header_charset)
# Send the message via SMTP to localhost:25
smtp = SMTP("localhost")
smtp.sendmail(sender, recipient, msg.as_string())
smtp.quit()
Once ported, this should get your code working. Hopefully, better support for RFC2047 and RFC3490 will be added soon. For now, you regrettably have to hack around the issue.