ARROW-6260: [Website] Use deploy key on Travis to build and push to asf-site

[nealrichardson]

This change enables the use of GitHub deploy keys, which are tied to a repository and not an individual (in contrast with personal access tokens). Once this is merged, we can add a key pair to the repository settings in GitHub and Travis (INFRA may be required to do one or both of those) and then commits to the website source in the master branch will automatically build and push the generated static site to the asf-site branch.

[kou]

+1
I left some comments.

[kou]

Could you use one of -z "..." style or "..." != "" style in this script for consistency?

[nealrichardson]

Thanks! Done, PTAL.

[kou]

We can use ssh-add - here:

echo "${DEPLOY_KEY}" | sed -e 's/\\n/\n/g' | ssh-add -

[nealrichardson]

Done, nice to avoid making that file

[kou]

Can we use s/\\n/\n/g here?

It works well with bash on my Debian GNU/Linux:

#!/bin/bash

DEPLOY_KEY="-----BEGIN\ OPENSSH\ PRIVATE\ KEY-----\\naaa\\nbbb"
echo "${DEPLOY_KEY}"
echo "${DEPLOY_KEY}" | sed -e 's/\\n/\n/g'

$ /tmp/a.sh
-----BEGIN\ OPENSSH\ PRIVATE\ KEY-----\naaa\nbbb
-----BEGIN\ OPENSSH\ PRIVATE\ KEY-----
aaa
bbb

[nealrichardson]

Didn't work on my mac but it doesn't have to as long as it works on Travis ;)

I'll give it a shot.

[nealrichardson]

Seems to work.

[kou]

Thanks for the try!

[nealrichardson]

Thanks for always managing to teach me a new bash trick :)