I have a .Net application. I want this application to send an email to me. How do I implement this without installing an SMTP server?
Using an SmtpClient to send a MailMessage does not require you to have a server on your local machine.
Your e-mail service provider is the one with the server (e.g. smtp.gmail.com), and your SmtpClient talks to it.
This article by Peter Bromberg on eggheadcafe.com
C# SMTP Mail without SMTP Service or CDO
explains how to send email without relying on an SMTP client:
Sending email via TCP using the native
SMTP RFC commands "HELO", "MAIL From",
RCPT TO", etc. is no big deal. That's
one of the first tricks we learn with
Telnet. Finding or writing managed
code that will do so reliably is
another story. The code in the class
that follows is not my original code -
I've cobbled it together from three
different sample sources, fixing
namespaces, error handling, and other
minor items, changing console code to
class library code, and providing a
complete Winforms - based test harness
front end that illustrates its correct
usage.
I've also included sample code
to correctly process and add a mail
attachment via an OpenFileDialog here.
This code MIME encodes and transmits
the attachment(s) according to the
specification.
You can't send email without the services of a SMTP server, there is of course no need for you to install one, just point your code at your ISPs SMTP server or your companies Exchange server (or what ever they use).
Related
Java 8 here, although this really is more of a generic Exchange/SMTP question I suppose.
I purchased a domain name and Office 365 support from GoDaddy, and as a result, have several email addresses through them. Let's say one of these is support#myapp.example.com.
I am writing a Java 8 app that will allow users to send emails to this support address (through the app). I will likely use the excellent Simple Java Mail library, which wraps the Java Mail API. And so somewhere in my app there will be some code that looks something like:
Email email = EmailBuilder.startingBlank()
.to("MyApp Help Desk", "support#myapp.example.com")
.withSubject("Support Ticket #12345")
.withPlainText("Something went wrong inside the MyApp!")
.buildEmail();
Mailer mailer = MailerBuilder
.withSMTPServer("smtp.host.com", 587, "user#host.com", "password")
.withTransportStrategy(TransportStrategy.SMTP_TLS)
.withProperty("mail.smtp.sendpartial", true)
.buildMailer();
mailer.sendMail(email);
Pretty straight-forward stuff, right? Except I'm confused about one simple thing: which SMTP server am I using here? Would I use the Microsoft Exchange server that my GoDaddy account provides me, or would I choose something else?
That depends a little bit on what you want to do.
If you just want to make one attempt to send the mail, you connect to the mail server that accepts mail for support#myapp.example.com. It sounds like this is an office365 server owned by Microsoft that accepts mail for myapp.example.com. There should be public DNS records for that domain. I haven't used the Simple Java Mail library, but from your pseudocode, I assume it does the DNS lookups for you.
It sometimes happens that an application encounters errors when trying to send an email. For example, somebody could restart your app server in the middle of the smtp conversation, or reboot your router, or something else. It's pretty common to use a Mail Transfer Agent (MTA) such as Exchange to help make this process more robust. If the MTA fails on the first delivery attempt, it will retry delivery for some configurable period of time. In your case, you could send the email to your Exchange server, and it would route the email to myapp.example.com.
(In this case, Exchange is sort of acting as a Mail Submission Agent (MSA), but that's kind of a nitpick.)
Hope this helps.
I have an application hosted in an Amazon EC2 Server that uses e-mail service from a shared web host. I did this to utilize the shared hosting e-mail server and the available e-mail administration tool and webmail interface.
My application uses amazon SES to send e-mail. I just authorized SES to send mails with my domain name (by adding some entries to my dns records and confirming I'm the domain owner), and this is working ok. When I need to send a mail, I connect to SES SMTP server and send it using PHPMailer.
Everything is working ok, except my mails are getting the DOS_OUTLOOK_TO_MX flag in SpamAsssasin's, making it sometimes be classified as spam.
What this flag means? Is there some way to avoid it?
Spamassassin DOS_OUTLOOK_TO_MX rule is fired when two internal flags are set by processed message: __DOS_DIRECT_TO_MX and __ANY_OUTLOOK_MUA.
__DOS_DIRECT_TO_MX flag means that the message was sent directly from sender email client to recipient MTA server. This is usually true for internal mail but can occur in your case when a recipient also uses Amazon SES for mail processing.
__ANY_OUTLOOK_MUA flag means that the message has X-Mailer =~ /^Microsoft (?:Office )?Outlook\b/ header.
Both internal flags are harmless by themselves but their combination leads to DOS_OUTLOOK_TO_MX with high spam score. You need to check X-Mailer header of messages sent with PHPMailer. This header should be set to PHPMailer, not to Microsoft Outlook or something similar.
On Mac, I can send email from command line using the command mail, but definitely I don't have SMTP server installed on my MacBookPro.
So, it is possible to send email with Ruby without an SMTP server? I don't care about the speed, I just want a way to send email without additional software needed.
You could just call the mail command from within your Ruby code. Use system or backticks or something more sophisticated like open3 to interact with system commands... Here is a nice overview over the different methods: http://mentalized.net/journal/2010/03/08/5_ways_to_run_commands_from_ruby/
About mail and sendmail
I don't know much about mail, but results from a quick search on Google seem to indicate that it uses postfix, which is the default SMTP server that is installed on Macs. In other words, you have installed and are running a SMTP server on your Macbook Pro.
About Ruby
So, it is possible to send email with Ruby without an SMTP server?
Yes and No. You don't need to have a SMTP server running on the same machine as your Ruby process. In fact, you don't even need to run your own SMTP server. However, you need a SMTP server somewhere to send your email.
About SMTP
This article on howstuffworks gives a good explanation of what SMTP does. Essentially, you need a SMTP server somewhere that accepts your email, talks to other SMTP servers, and passes your email on for delivery. With Ruby, you can configure Net::SMTP to connect to a SMTP server of your choice.
About What You Are Trying To Do
If you want to write and execute a script that will deliver a small number of email messages, create a fake email account on Gmail/Live and use their SMTP servers for sending email.
If you want to build and launch an app that will deliver emails to your users, use Mandrill, MailGun, or SendGrid. Mandrill has a free tier for you to get started.
I don't recommend running your own SMTP server for most use cases, because your emails will likely be marked as spam. (Comcast might also think that you have malware on your network.) Professional services like Mandrill will help you setup SPF and DKIM records to authenticate your emails and improve sending reputation.
(If you just want to test email in dev mode, use MailCatcher.)
Conclusion
Sign up for a Mandrill account, then use Net::SMTP in Ruby to connect to their SMTP servers. No additional software is required.
If your mail command is working, then you can send mail from within
ruby. And if your mail command is working on your mac already, then
you also already have an SMTP server working on your mac, since by
default it uses postfix which comes installed. The mail command
defaults to using /usr/sbin/sendmail, which is in this case an
interface to postfix. (Try man sendmail from the Terminal.)
Now, that said, you will probably experience something like this when trying to use Net::SMTP locally:
[3] pry(main)> smtp = Net::SMTP.start('localhost',25)
Errno::ECONNREFUSED: Connection refused - connect(2)
This means that you need to do something to tell your mac that it can
accept connections on port 25. Another alternative is to use that
sendmail program as a transport access method, which might actually be the
better option. The port 25 access is turned off so that no one else
can use your mac as a mail relay. Having to go through the sendmail
command means that only programs on your mac can send mail (go
figure).
My suggestion here would be to use the mail gem (or pony if you
prefer) and configure it to use sendmail. From the mail README
file:
Sending via sendmail can be done like so:
mail = Mail.new do
from 'me#test.lindsaar.net'
to 'you#test.lindsaar.net'
subject 'Here is the image you wanted'
body File.read('body.txt')
add_file :filename => 'somefile.png', :content => File.read('/somefile.png')
end
mail.delivery_method :sendmail
mail.deliver
Likewise, if you're using ActionMailer you can configure it to use
sendmail as well.
Have you tried the Pony gem? It provides a really simple interface to sendmail, which should already be installed on your Mac.
Is your goal to write and send email from the CLI?
There's a number of mailer gems, including mail. You could probably also play directly with Ruby's Net::SMTP and get something working, depending on what you are trying to do.
You don't have to have an SMTP server, you just need to know where one is that you can connect to.
See Net::SMTP. It's part of Ruby.
If you used mail or /usr/sbin/sendmail command and your mail delivered successfully, then there was an MTA (Mail/Message transfer Agent eg. postfix, sendmail or whatever) running on your machine.
when you use your mail command to send a mail to guser#gmail.com,your mail command will submit the mail to local SMTP server.
(local) SMTP server will do the following tasks.
SMTP server(MTA) will do MX lookup for gmail.com
Connect to port 25 of MX server and hand over the mail by talking SMTP (HELO, MAIL FROM,RCPT TO,DATA commands)
Mx server will deliver the mail to the corresponding mailbox (guser).
The above answers suggest you to use Net::SMTP where you will connect to some SMTP server and hand over the mail to that SMTP server, which will again do the above tasks (of local SMTP server above) to perform the delivery.
So to send mail, u need an SMTP server. or you will have to code yourself/use some library to perform MX lookup and hand over the mail to the MX server by talking SMTP commands as per RFC 2821.
I have a web application running on Windows IIS. This app has a database where each item has a unique key (1, 2, 3...), and a list of email addresses (among other things).
I would like users to send email to the server, using an email address that identifies the item, then have the server relay the message to the email addresses for that item. For example, if a user sends email to the following address:
item-75#myserver.example.com
Then the server would receive the email and pipe it to a script. The script would query the database for item 75 to get a list of email addresses, then re-send the email.
I could do this easily on a unix system using sendmail, but I have no idea if a similar setup can be accomplished on a Windows system (or if it would require additional software).
(This sounds like you want to implement a feature like craigslist).
The IIS SMTP service can send email, and also accept email.
Here is what you want to do.
Configure your IIS SMTP service to accept emails for a domain (You can configure this in the properties of the IIS SMTP service, under domains). Say domain name "myserver.example.com"
Then, in your DNS server, configure a MX record that points to "myserver.example.com".
Now, when email gets sent to your IIS SMTP server, it will actually get placed in your mailroot/drop folder (you can also change this folder in the IIS SMTP Service properties).
Now that you are accepting email, the next step is to write a script that will:
1)Parse the emails.
2)Modify them accordingly (do you just want to change the "to" address?).
3)If you want to resend the emails, then you need to modify them accordingly.
You will need to add a single X-Sender header, that is used to identify the email address sending the email, and a X-Receiver header, for each recipient that is going to accept the email. Here is an example email that was modified:
X-Sender: me#mywebsite.com
X-Receiver: recip1#theirdomain.com
X-Receiver: recip2#theirdomain.com
From: "jim bob" <jim#example.com>
To: <item-75#myserver.example.com>
Subject: test
MIME-Version: 1.0
Content-Type: text/plain;
Message-ID: <024f01c9e130$b3eca500$0401a8c0#local>
test
Once you have this modified content, you will want to write it to a file in the mailroot/pickup directory. Be sure to use a unique name.
The IIS SMTP Service will come by, pickup the email, and relay it on, sending the email using the X-Sender as the MAIL FROM address, and sending it to each email address listed in each X-Receiver header.
4)Run this script as a scheduled task. Another option is to build it as a windows service, or to implement something like a filesystemwatcher, where it executes each time an email is created as a file.
5)Another option to all of this is to actually implement a SMTP Event Sink, but I think that is overkill for what you want to do, and can create more headaches, than it solves. I would only go the event sink route if I like pain.
Hopefully I didn't make that about as clear as mud.
Event Sinks aren't difficult at all! In fact, there are about a dozen examples written in VBS (which runs on a Win server using WSH) which accomplish exactly what you wish to do. The OnArrival event sink runs in REAL-TIME using any computer user account you wish w/o any security risk since the message is asynchronous and doesn't report back.
This is actually a terribly easy thing to do - one of the easiest. Once set up, it never breaks either. On one server I've had one running for more than 9 years processing a few thousand incoming messages per day! I've set up about a dozen of these things - if it takes you more than a couple hours, you're doing it very wrong. If it were any easier than this on UNIX, my grandmother could be a UNIX programmer so I wouldn't go bragging that this is easier to do on a UNIX server.
http://msdn.microsoft.com/en-us/library/ms528023.aspx
http://support.microsoft.com/kb/894286
http://msdn.microsoft.com/en-us/library/ms526206.aspx
http://msdn.microsoft.com/en-us/library/ms526620.aspx
You could read in email through POP3 or IMAP using a timed script. I'm also a UNIXer so I'm struggling to comprehend how something like this is so difficult, but there you have it. Here's what I reckon you should do.
Make a script in whatever language you like. As long as it can read from POP3 or IMAP.
Have Windows run the script every 5 minutes
Have the script access the mailbox and action any emails it needs to.
My personal preference would be to install Python, but if you're limited... I don't know. ASPNET isn't bad, but I've never used it for dirty-scripting before.
I am trying to send mail from a local iis app using localhost as my smtp server after installing free smtp but I am getting the following error:
Mailbox unavailable. The server response was: Invalid
recipient: 'validAddress'#hotmail.com
Any idea what the problem could be?
it sounds like your free (3rd party) smtp app is not leaving your network and might be trying to see if it has that mailbox itself. Try and see if there is a setting to allow the smtp server to access external connections, etc. What is the name of the free smtp app, btw?
Alternatively, can u use the built in SMTP mail provider, built into iis? do you know how to use that, instead of this 3rd party app.
It looks more like the SMTP service needs to be configured to "Relay" email... Usually this involves telling it what YOUR mail domain is, and then any mail destin for a domain other than it's own will cause it to go out to the world, and try to relay the message to the real server.
But, be careful! This is how spammers exploit email servers. They look for SMTP listeners that will relay for them. You want to make sure yours will only accept relay mail from "localhost", or whatever machine will be connecting to it to do the sending.
A more secure way is to block port 25 inbound at your firewall to this box, so this SMTP server is not visible to the outside world.
Write and test a simple smtp sender in C. It needs 3 minutes with RFC
Use Wireshark to see what comes on the wire between your application and the SMTP server.