Sunday, August 11, 2013

Pre-compiling Twig Templates

To be able to use option 'auto_reload'=>false in production with Twig, I need to be able to force a recompilation.  The easy way would be to clear the cache directory in the deployer when pushing an update, but if I'm micro-optimizing, why not ship built templates as part of the distribution?

The next obvious question is, "How do I make twig compile templates without rendering them?" and it turns out there's a simple answer.  The long form $twig->loadTemplate("name.twig")->render($vars) is the secret: loadTemplate writes to the cache if caching is enabled when the template is loaded.

Conceptually, then, it's dead simple: configure Twig how you normally would, list out all your template files, and call $twig->loadTemplate() on each of them.  I believe the minimal solution on POSIX platforms would look like this:

Wednesday, August 7, 2013

Smarty vs. Twig (a benchmark done poorly)

Note added 14 Feb 2014: I ended up settling on Twig without too much more rigorous testing.  This used to be titled "Part 1" but there is, and is never expected to be, a Part 2.  Now back to your original post....

I'm pretty cranky about what my templates do (I have been known to roll my own), so I have a small list of must-have features.  Listing in order by increasing likelihood that a template engine satisfies them:
  • Extensible functions for adding convenience from the host environment
  • Built-in functions for date formatting
  • No annoying <? ?> all over the place
  • Auto-escaping of variables when building HTML
  • Conditionals, expressions, and loops (if-elseif-else chains, boolean logic)
  • Access to array elements and object properties
That's pretty much it: I'm willing to let "presentation logic" get pretty heavyweight, as long as it involves read-only access to the variables given to the template.  Templates should in no way mutate their model or context (excepting functions they initiate, like cycle, for hopefully obvious reasons.)

With that, it looks like the contenders are Smarty and Twig, currently at versions 3.1.14 and 1.13.2, respectively.  How do they compare in a benchmark showdown?

Thursday, August 1, 2013

Working from Home

Since I've radically changed my work VM configuration, I needed to change my home PC in order to connect properly to the new setup.

Before we dive in, a brief review of the old setup: the host at work, which we will call `audia`, ran a VirtualBox guest named `dev`.  dev had its own set of configs and configuration knobs so that I could write dev.audia.pc dev into /etc/hosts, point Firefox to dev:10080, and code running on dev would be able to recognize "this is development," not require TLS, and know that http://dev:10080/ is the URI root of the app.  I configured VirtualBox's port forwarding to listen on from audia, and when I connected to the VPN, my home computer (call it `starlet`) had its own /etc/hosts listing that used the internal IP of audia for dev.  The same URI from home would then get connected via port-forwarding to the dev VM.

This all changed when I wanted to test a SAN certificate and some redirection rules.  I didn't want certificate mismatch errors in Firefox, and I needed dev to think it was the production server so that it would use the production ruleset.  That became the underlying justification for devproxy.  After that point, dev had the production certificates, hostnames, and rules.  It had a host-only network added, which audia now used, and I took out the port forward.  (This was the problem behind getting Lost in the Complexity.)

But without the port forward, starlet can't reach dev anymore, only audia.  Of course, I came up with a solution:

(Despite what may be implied, the VPN isn't connected to starlet.  I just didn't feel like redrawing the whole tube.)