Dummy SMTP server for development purposes

Question

I've been using a dummy smtp server called DevNull SMTP so that I can test my app which sends out notification emails. It has a nice simple GUI, very helpful, but can't be scripted easily. I can't even start it listening to port 25. I have to run the app and then click on the start button...

Is there a similar app that can be scripted easily? Scripted in the sense that I can control it from a bash script or windows batch file and possibly even query the emails from my unit/functional tests.

you can take a look at the answers posted at http://stackoverflow.com/questions/550887/testing-smtp-with-net — wimh, May 01 '11 at 07:45
Checkout mailnest.io. It is one of the best email testing solutions available in the market. It also has a free plan to start with. — Anish John, Aug 10 '20 at 10:51

score 105 · Accepted Answer · edited Jan 16 '21 at 13:23

105

there is a nice trick with python: http://muffinresearch.co.uk/archives/2010/10/15/fake-smtp-server-with-python/

Just one liner can do the job (listens on port 2500):

python -m smtpd -n -c DebuggingServer localhost:2500

edited Jan 16 '21 at 13:23

Chris Stryczynski

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answered Jun 14 '11 at 13:28

Mic

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legend - incredibly useful! – Chris Nov 24 '11 at 07:03
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That is the most useful trick I have seen in programming, ever. – Teekin Jan 13 '14 at 21:15
One line. No installation. Job done! – randomsock Oct 10 '19 at 18:51

isNaN1247 · Answer 2 · 2014-01-18T08:18:17.550

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Disclaimer - I work for the company behind this service linked to below.

You can also use a hosted email testing service like Mailosaur. Some of them (ours included) come with an API for integrating into your tests.

That way if you hit a problem you've got someone else to do the hard work in adding new features, etc. for you.

edited Jan 18 '14 at 08:18

answered Jan 15 '13 at 08:42

isNaN1247

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score 1 · Answer 3 · answered Nov 28 '12 at 14:03

I had a similar problem. Since I stumbled during my research over this question, here is what I ended up with:

For unit testing you can use subethasmtp. Base on subethasmtp I also wrote a program that you can use to call from scripts an query the results: developmentSMTP

Dummy SMTP server for development purposes

3 Answers3