Add host option to serve on other than localhost

[SndR85]

I wanted an option to do serve on a other IP-address that localhost. This change make it possible to add -h / --host option te set a different IP-adress the webserver will listen on.

I have made the change quite simple. My ruby knowledge is not great and I have not tested the change fully. I could not get the spec-test working and have not changed it. I tested that it was running on 0.0.0.0 when I run reveal-ck serve -h 0.0.0.0 and it did. Also the banner is printing the current address specified by -h.

[kbrock]

I had thought that reveal-ck serve was more of a development thing. So serving to non localhost seems odd to me. (but just because it doesn't meet my use case doesn't mean anything really)

Would it make sense to just serve everything off of 0.0.0.0 and not add this flag at all?
I mean, fewer flags in my book is better. And if this is not intended to be run on a production box, then opening up to loopback or to a remote seems good.

[jedcn]

Interesting idea! What's your motivation? Do you want to serve on 0.0.0.0 so that people cannot accidentally view your presentation while you're working on it? Or is there another reason?

What value of --host do you anticipate using?

...

No worries about the failing build. This thing is picky. I'll take a look later on tonight.

[kbrock]

@jedcn actually it is the opposite. I think the old default value was localhost - saying no one can view it except via the loopback interface - so it will only work on the machine at network address localhost / 127.0.0.1.

A value of 0.0.0.0 says to bind on all network interfaces, so anyone can view it, even from remote hosts.

Rails in development mode has you type -b 0.0.0.0 to allow other machines to connect.

[SndR85]

The use case for me was to see if I can run reveal-ck in Docker. And to expose serve te the world outside the container, you need to set 0.0.0.0 as listen-address, so that anybody from outside the container can connect to reveal-ck.

And yes, 127.0.0.1 (or localhost) is intended to be connected only local, not from the outside. 0.0.0.0 is world accessable. See also: https://en.wikipedia.org/wiki/0.0.0.0.

[jedcn]

Okay, cool. I'm convinced. I'll either:

1. add --host, or
2. default to 0.0.0.0, or
3. do both

Should be out in a few days, the end of the coming weekend at the latest.

Speak up if you need it sooner.

Thanks for the PR @scornelissen85.

Thanks for chiming in @kbrock.

[jedcn]

I re-used the commits from this PR and opened up #81.

I added some administrative commits on top of yours.

I'll do a bit of testing to make sure things are working as expected and we should be good to go.

Once I merge #81 in, I'll close this one (#79) but your code and your authorship of it will still be used.

Thanks!

[jedcn]

Pull #81 has been merged in and released. The released version is 3.5.0:

https://rubygems.org/gems/reveal-ck

Please check it out and see if it works for your use case: https://rubygems.org/gems/reveal-ck/versions/3.5.0

I'm going to shortly be releasing version 3.5.1 which will change around a bunch of gems. This could impact you-- that's why I released your requested change first.

If you don't get around to testing for a few days, you'll grab version 3.5.1 and if that doesn't work (say, due to gems) please try explicitly using 3.5.0.

I'm going to close this PR now. Thanks again.