I need advises on how to best setup a test environment for testing of mainly HTML5, Node.js apps which will be updated by diverse developers via Git and then tested by users around the World. When a revision is fully tested on all devices and code reviewed the release code shall be easily deployed with one command to the public live server, which might be a separate VPS/droplet at DigitalOcean. The current public live server now runs Ubuntu 12.04 64bit LEMP. We want to keep the two environments securely separate. In the event of an attack on the live server we want to be able to temporarily switch IPs of domain to point to the "test"-environment instead.
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