Automatic TWiki Deployment

This is a follow-up to my blog article with the same name. Over there, I wrote about why, and here's the how.

Generally speaking, I am following the idea of "Infrastructure as Code" (see Wikipedia): The whole system is defined in plain text files, which can (and should!) easily be kept under version control. The text files are a "Vagrantfile" to define a VM and a bunch of YAML files for Ansible to define the configuration.

The current doc has two parts:

• Part 1: Installation and configuration
• Part 2: Running the playbooks

I am slightly concerned that this stuff introduces too many different tools and techniques into the mix, though only a tiny fraction of their features is needed. It is a trade-off: I happen to be sufficiently comfortable with Ansible and Vagrant, therefore it was easier to just use these tools instead of writing the same automation procedures focused on TWiki deployment myself.

Things to consider:

• As of today, the playbooks automate deployment of one TWiki configuration with one web server (Apache). The only choice is the distribution, but this is restricted to Debian and Ubuntu. Other distributions need more work because of their different packaging tools (and package names!). How many different sets of configurations are useful?
• A playbook to deploy TWiki could live a life of its own, and maybe be published in the Ansible repository. How relevant is Ansible to the TWiki market?
• To what extent can this stuff be used for test automation? I'm currently experimenting with this topic.
• All that is totally independent of the TWiki codebase itself, with a separate versioning, and irrelevant for TWiki customers. Should it go into a separate repository, e.g. on github? Or merged into TWikiDevContrib (which is in SVN, but not in Plugins)?
• The whole concept defines the configuration of the operating system, the web server, and TWiki into some "Uber-config". Is it useful to create one uber-config file to specify all different options?

-- Contributors: Harald Jörg - 2018-01-08

Discussion

After working with this stuff for some time I found it too cumbersome to remember the parameters and syntax for direct use of the Ansible commands from "running the playbooks" - so I now merged it into TWikiDevContrib in SVN. There are now four subcommands related to VMs. The command framework (CPAN:MooseX::App::Cmd) has the big advantage that it is rather self-documenting... so here's what the command says as of today:

haj@hajdesktop:~$ twikidev
twikidev <command> [-?h] [long options...]
        -? -h --help  show help

Available commands:

Getting help:
      help: display a command's help screen
  commands: list the application's commands

Managing SVN:
       t2b: Copy file(s) from trunk to a branch

Building distributables:
   collect: collect all stuff from one or more MANIFEST files to a directory
   extract: Extract a tar, tar.gz, or zip archive
   packtwp: Take a directory tree from collect and create an executable

Managing a test environment:
  vmconfig: Configure your VM test environment
  vmcreate: Create a new VM in your test environment
  vmstatus: Show status information about a VM
  vmdelete: Delete a VM by its IP address suffix

-- Harald Jörg - 2018-02-15

Cool!

-- Peter Thoeny - 2018-02-15