Gemfile: source ruby gems from optional RUBY_GEMS_MIRROR env value

[kimago]

TNZ-67131

Authored-by: Kim Bassett kim.bassett@broadcom.com

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[abg]

@kimago I don't think you actually need this. You can override the mirror with existing features in the ruby ecosystem.

Here is an example using the BUNDLE_* environment variables.

## Old pxc-release Gemfile
# grep source Gemfile
source "https://rubygems.org"

## Break rubygems.org so we HAVE to use a mirror to prove the below suggestion works 
# cat >> /etc/hosts <<EOF
127.0.0.1 rubygems.org
127.0.0.1 index.rubygems.org
EOF 

# bundle install
...
Bundler::HTTPError Could not fetch specs from https://rubygems.org/ due to underlying error <Errno::ECONNREFUSED: Failed to open TCP connection to rubygems.org:443 (Connection refused - connect(2) for "rubygems.org" port 443) (https://rubygems.org/specs.4.8.gz)>
...


# export BUNDLE_MIRROR__RUBYGEMS__ORG="https://your.mirror/ruby/gems/endpoint" # <- url
# export BUNDLE_YOUR__DOMAIN__COM="$USERNAME:$PASSWORD" # <- credentials, usually via a secret
# bundle install --verbose
...
The definition is missing ["bosh-template-2.4.0", ...]
HTTP GET https://$USERNAME@your.mirror/ruby/gems/endpoint/versions
HTTP 200  https://$USERNAME@your.mirror/ruby/gems/endpoint/versions
...

# bundle exec rspec spec
......................................................................................................

Finished in 3.73 seconds (files took 0.63424 seconds to load)
102 examples, 0 failures

Can you let us know if this works for you?

[colins]

Using the bundler mirror settings will fallback to the rubygems.org (or whatever is in the Gemfile) if the mirror doesn't respond.
https://bundler.io/man/bundle-config.1.html#MIRRORS-OF-GEM-SOURCE

[abg]

Using the bundler mirror settings will fallback to the rubygems.org (or whatever is in the Gemfile) if the mirror doesn't respond.

That's fair. I withdraw my suggestion.

I went back and tested this behavior, but I didn't really see the fallback. Looks like if you do not set a fallback timeout or set it to zero, bundle install still just fails. Maybe a thin contract to rely on still.

Regardless, I approved this change.