One of the major advantages of the high career mobility in SF … Cross pollination. Yet each new codebase I comes to seems to lack a few of the following. So I figured I’d list out the essentials that every web codebase should have.
- The Obvious: Git, IDE, MV*, relational DB, 3 environments that match production.
- Language regularization:Each language has its own idiosyncrasies. Learn your languages weakness and make helper functions to accommodate. In PHP, these weaknesses include single-threaded, bad undefined index default behavior.My preferred solution to PHP’s single-threaded limitations is to make use of a job queue. This will emulate additional threads for heavy tasks (e.g. sending emails to all of your user base) or high-latency tasks that ideally should be asynchronous (e.g. certain API calls). I’ve seen this done well, and I’ve seen it done poorly. From experience, I’d point out the following lessons: don’t use a message queue as a job queue and the DB is a great place to store a home-grown job queue [because it provides great visibility, resilience, can be controlled programatically, can be exported to disk, is atomic, etc].
In PHP, out-of-bound reads on arrays return null and log a notification to the event log. As this is never the engineer’s intent, I always write two helper functions. One that looks up an key and returns a specific value if the key isn’t found (for cases where you’re using the array as a set). The other function looks up the key and returns an exception if the key is not found (for normal cases where the key should always be present).
- A powerful, generic staging environmentOne of the most impressive and useful technologies I saw was something we called humblebrag. It was a script that caught all requests to *.company.com/…. It then took the *, checked-out the corresponding git branch, and mapped the request to that particular branch. Thus in effect, we had a zero-effort way to have all branches usable simultaneously on a single server, even by non-engineers.Doing this can be a little harder in more complex environments with versioned services listening on ports, if you don’t plan for it early.
- A circuit breaker. Download one from github.
- An ability to do cross-server mutexes.
- A simple, generic read-through-caching function.
- A powerful logging system connected to an alerting system
- An A/B test system. Even if you’re not doing A/B tests on user-experience, it can be a great way to rollout to a small portion of users or internal-testers to ensure stability on a new environment.