This is a guest post by Albin Sunnanbo introducing a great hack to work with mails in test environments.
If you have a .NET application that sends emails, this is probably something for you.
TL;DR;
PickupMailViewer is a simple web viewer for emails saved by the specifiedPickupDirectory SMTP setting in a .NET application.
Download the source, publish to your test server, configure pickup directory and you should be up and running within five minutes.
Outgoing Emails in Test Environments
In your test environment will typically not send real emails, but rather use the specifiedPickupDirectory delivery method for your SMTP-settings in web.config. This puts all outgoing emails as *.eml files in the file system instead of sending real emails.
IMHO that is the way to go regarding emails in your test environment.
However, there is one drawback, the emails gets dropped in a folder somewhere on your test server. Typically in a location that nobody looks at regularly. In my case I first have to connect a VPN, then open a remote desktop connection to our server, open the folder and copy the desired file back to my own computer (no eml viewer, a.k.a. Outlook, on the test server) and finally open it in Outlook.
Even worse for our testers that don’t even have permissions to login on the test machine. They have to ask a developer to get their emails out of the test system. As you can imagine this only happens when it is absolutely necessary.
When developing a system that sends mails, often the mails shouldn’t be sent for real when testing. Instead they should be made available for investigation. Fortunately, that functionality is built in with the .NET SmtpClient.
There is even no need to change the code. It’s just a matter of configuration. Add the following lines to the app.config (or web.config for web applications)
<system.net><mailSettings><smtpdeliveryMethod="SpecifiedPickupDirectory"from="[email protected]"><specifiedPickupDirectorypickupDirectoryLocation="c:\temp"/><!-- The network host setting isn't used, but without it an exception occurs when disposing of the SmtpClient.--><networkhost="localhost"/></smtp></mailSettings></system.net>
<system.net>
<mailSettings>
<smtp deliveryMethod="SpecifiedPickupDirectory" from="[email protected]">
<specifiedPickupDirectory pickupDirectoryLocation="c:\temp" />
<!-- The network host setting isn't used, but without it an exception
occurs when disposing of the SmtpClient.-->
<network host="localhost"/>
</smtp>
</mailSettings>
</system.net>
The pickup directory setting is meant to be used with a local mail server that watches a directory for new mails. I have no mail server watching my c:\temp directory. Instead, the mails are just dropped there as .eml-files that can be opened using a mail program (e.g. outlook).
When developing a system that sends mails, often the mails shouldn’t be sent for real when testing. Instead they should be made available for investigation. Fortunately, that functionality is built in with the .NET SmtpClient.
