Basic Confusion about ActionMailer RoR

Question

I'm fairly new to Ruby on Rails and actually entirely new to website mailing. In a lot of example tutorials I see a "from" object assigned to, for example, "new@example.com". When I setup the emailing functionality on a localhost the RoR command prompt says that everything finished fine even when I keep "new@example.com" as the from object. Can I actually mail from a localhost port? What would I have to put as my "from" address in order to actually send mail from the my local web application? Just a regular email I have? How would it be authenticated to ensure that the "from" address is actually the real address?

It seems a really fundamental concept and I understand all the model/view/controller actions that have to be done to make it work but I'm confused I guess as to how it actually works

Answer 1

In general the from field can be anything.

Some mail servers may take action if they think that you are claiming to be someone you are not, such as blocking mail or marking it as spam (via mechanisms such as DKIM or SPF). These are done at the domain level, ie the mail server tries to work out whether the server talking to it is allowed to send email claiming to be from @example.com.

Other mail servers mail just silently rewrite your from field if they know who you are, for example if you are talking to the gmail smtp servers and have authenticated as bob then the from field will be set to bob@gmail.com, unless it is already set to an email address gmail knows you own.

By default, in development rails doesn't try and send email at all. For it to send email you need to configure the deluvery_method, usually this involves either setting it to :sendmail (if you have an appropriately configured instance of sendmail running locally) or setting to :smtp and also providing details of an smtp server to use.