Logging to Stdout with Monolog

My worker scripts have really basic logging (as in, they echo when something happens, and I can see those in the supervisord logs). Which is kind of okay, but I wanted to at least add timestamps in to them, and maybe send emails when something REALLY bad happened.

I'm a huge fan of Monolog so I grabbed that, but it wasn't immediately obvious which of the many and varied options I would need for this fairly simple addition. It turns out that the right thing to use is the ErrorLogHandler, so now my code looks like this:

<?php

require "vendor/autoload.php";

$logger = new \Monolog\Logger("log");
$logger->pushHandler(new \Monolog\Handler\ErrorLogHandler());

$logger->addInfo("Something happened");

And the output is neatly in lines like this:

[2014-06-05 17:00:47] log.INFO: Something happened [] []

You can do a lot of different things with Monolog, but since I had to look up this simplest of all options, I thought I'd share.

Colourless Git Output

I teach git and often have issues with bad projectors where you can't see the colours. Recently I had a setup where even white on black was more or less invisible, but using black text on a white background worked okay. There's lots of documentation on how to turn on colours in git but not so much about how to turn them off.

Try putting the following into .git/config:

[color]
    branch = false
    diff = false
    interactive = false
    status = false

I had expected to be able to set color.ui to false but that didn't seem to make much difference, so I now use the settings above. I thought I'd drop it here in case anyone else is looking for the same thing.

Easy Lint Check for JavaScript

I'm introducing lint checking on one of my projects, because it didn't have a build process yet and I love this as a great place to start. Oh, and because we managed to commit broken syntax! So I set up a php lint job (I will share my travis config in another post) and tried to work out doing the same thing for JavaScript. Continue reading

Beanstalk, Pheanstalk and Priorities

I've got an application that uses Beanstalkd to queue up messages, and some PHP worker scripts that grab messages from the queue and process them. Messages get added by the web application, but can also be added by cron - and when I add a bunch of messages via cron, I don't want to swamp what the web application is doing! Those cron-added jobs are mostly pretty low priority, generating reports, sending weekly update emails, that kind of thing. Beanstalkd has a concept of priority, so I can create lower priority jobs by using code like this:

<?php

define("LOW_PRIORITY", 2048);  // default is 1024 

$queue =  new Pheanstalk_Pheanstalk($config['beanstalkd']['host'] . ":" . $config['beanstalkd']['port']);

$queue->useTube("scorem")->put(json_encode(array("action" => "my_important_task")), LOW_PRIORITY);

This will add the job to the queue, but anything with a higher priority value (where 1 is the highest priority!) will take precendence. This way I can add as many non-urgent jobs as I want to to the queue without impacting my website performance. My setup has multiple workers and also I tend to write a script that puts loads of tiny jobs on the queue rather than putting one monster task on there. I find this approach a bit more fault-tolerant and also means that incoming tasks can get a chance to get serviced rather than waiting for some crazy huge thing to finish.

I had real issues finding information about the priority settings for beanstalkd and PHP, so hopefully if anyone is looking for it, they will find this post :)

Copy/Pasting and Vim

I'm a vim user and I somehow completely missed this excellent feature until much more recently than I care to admit! Usually vim has its own clipboard, but it doesn't share with the operating system. You will need a vim-gtk install, this isn't available in really basic vim (I'm a little unclear exactly on the dependencies).

To paste between vim and something else, use the + (plus) buffer in vim. It contains the contents of your system clipboard, and you can also write to it. If you're not already using buffers in vim, then you should probably read the excellent documentation but for a very quick start:

  • To copy something into the buffer, select it in visual mode and type "+y
  • To paste from the buffer, type "+P

I had no idea how I'd missed this really fundamental trick, so I thought I'd share!

Quick Switch Between Git Branches

Today's little-known git feature (or maybe everyone knows but me? I only found this a few months ago) is for quickly switching between branches. Usually I would switch branches with:

git checkout [branchname]

However if you switch from one branch to another and want to switch back again (this happens when I'm reviewing changes and wondering if a bug is present on master as well), then you can do so by just doing:

git checkout -

Just a little timesaver in case it's useful to anyone else - I know I've been using it quite a bit!

Wireshark Capture on Remote Server

The joind.in project uses a really nice vagrant setup for its dev platform - which is much needed these days as we move away from a single LAMP stack install to a website plus another website, which talks to an API and caches in redis and deploys with .... you get the picture :) This is great but having everything on the VM can make it a bit trickier to debug what's going on - and with a website that talks to an API that talks to MySQL, that all lives on a VM with port forwards, you can see the problem :)

To get an insight into the traffic going around the place, I've been using Wireshark and it's ability to capture remotely, it's really simple so I thought I'd write down my "recipe" on how to do this in case it's useful. Continue reading

PHP 5.6 and the Splat Operator

We have a couple of new features coming in to PHP 5.6 with names that sound much less exciting than the features they actually represent: "variadic functions" sound positively academic, and "argument unpacking" isn't exactly catchy. However they both use a new operator in PHP which looks like an elipsis (three dots ...) and is referred to as either the splat operator or the scatter operator. I included them in a recent version of my "Upgrading PHP" talk so I thought I'd share the examples here too in case anyone is interested. Continue reading

Using Composer Without GitIgnoring Vendor/

Recent additions to the joind.in API have introduced some new dependencies so we decided we'd start using Composer to manage these - but we don't want to run composer unsupervised. I'm sure this will bring the rain of "just run composer install, it's probably mostly almost safe" criticism, but actually it's quite tricky to run Composer without excluding vendor/ from source control so I thought I'd share how we did it so that anyone who wants to do so can learn from my experience!
Continue reading