The Difference Between UI and UX

Via this article (in Russian), I came across this blog post discussing the differences between the design of the UI (user interface) and the UX (user experience).

In many cases, the incorrect expectation is that an interface designer by default understands or focuses on user experience because their work is in direct contact with the user. The simple fact is that user interface is not user experience. The confusion may simply be because both abbreviations start with the letter “U”. More likely, it stems from the overlap of the skill-sets involved in both disciplines. They are certainly related areas, and in fact many designers are knowledgeable and competent in both.

However, despite the overlap, both fields are substantially different in nature and – more importantly – in their overall objectives and scope. User interface is focused on the actual elements that interact with the user – basically, the physical and technical methods of input and output. UI refers to the aggregation of approaches and elements that allow the user to interact with a system. This does not address details such as how the user reacts to the system, remembers the system and re-uses it.

Nginx Amplify : comprehensive Nginx monitoring

Somehow I missed the announcement of the Nginx Amplify (beta) back in November of last year, so here it goes now.

Nginx Amplify is a new tool for the comprehensive monitoring of Nginx web servers.  Here’s what it can do for you:

  • Visually identify performance bottlenecks, overloaded servers, or potential DDoS attacks
  • Improve and optimize NGINX performance with intelligent advice and recommendations
  • Get alerts when something is wrong with the delivery of your application
  • Plan capacity and performance for web applications
  • Keep track of systems running NGINX

As well

as the regular proactive monitoring of the Nginx issues.  Have a look at the documentation for more details.

Getting started with workflows in PHP

For a large project at work, we need to integrate or develop a workflow engine.  I worked a little bit with workflow engines in the past, but the subject is way to big and complex for me to claim any expertise in it.

So, I am looking at what’s available these days and what are our options.  This post is a collection of initial links and thoughts, and it’s goal is mostly to document my research process and findings, and not to provide any answers or solutions yet.

Continue reading “Getting started with workflows in PHP”

CakePHP 3 : Remove Shell Welcome Header

CakePHP 3 has an excellent support for command line Shells, Tasks, and Console Tools.  There are a few that are bundled with the framework itself, and that come from a variety of plugins.  And, of course, you can have your own commands, specific to your application.

$ ./bin/cake

Welcome to CakePHP v3.4.3 Console
---------------------------------------------------------------
App : src
Path: /home/leonid/Work/cakephp_test/src/
PHP : 7.0.16
---------------------------------------------------------------
Current Paths:

* app:  src
* root: /home/leonid/Work/cakephp_test
* core: /home/leonid/Work/cakephp_test/vendor/cakephp/cakephp

Available Shells:

[Bake] bake

[DebugKit] benchmark, whitespace

[Migrations] migrations

[CORE] cache, i18n, orm_cache, plugin, routes, server

[app] console

To run an app or core command, type `cake shell_name [args]`
To run a plugin command, type `cake Plugin.shell_name [args]`
To get help on a specific command, type `cake shell_name --help`

There is one tiny little annoyance though.  Sometimes, it’s useful to get an output of the CakePHP Shell and use it in another script.  For example, you might need to get a list of all loaded plugins and loop over them, performing another action, outside of CakePHP.  Say, in a bash script.  Getting a list of loaded plugins is easy with the bundled shell like so:

$ ./bin/cake plugin loaded

Welcome to CakePHP v3.4.3 Console
---------------------------------------------------------------
App : src
Path: /home/leonid/Work/cakephp_test/src/
PHP : 7.0.16
---------------------------------------------------------------
Bake
DebugKit
Migrations

But, as you can see, the output is not very useful for machine processing. The welcome header is in the way.  Sure, you can parse it out with regular expressions, or even a simple line count.  But that lacks elegance.  Is there a better way?  I thought there was.

My first approach was to use the –quiet option, which, I thought, would leave me with just the needed output.  It turns out, that’s not what it does.  It strips out all the output, and there is no list of plugins at all.

The second approach worked out better.  I learned about it from this thread.  The solution is to extend the needed CakePHP shell and overwrite the protected _welcome() method.  Here’s the content of the newly created application level shell in src/Shell/PluginShell.php:

<?php
namespace App\Shell;

use Cake\Shell\PluginShell as Shell;

class PluginShell extends Shell
{
    /**
     * Silence the welcome message
     *
     * @return void
     */
    protected function _welcome()
    {
    }
}

And now running the same command as before produces a cleaner output:

$ ./bin/cake plugin loaded
Bake
DebugKit
Migrations

This now can be easily used in other scripts without any need for regular expressions and other trimming techniques.

GitHub adds Open Source license descriptions

GitHub added Open Source license descriptions.  This is a tiny, but very useful feature, especially for those people who are not very well versed in the differences between GPL, MIT, BSD, and other licenses.  I wish there was a way to have something like this proprietary applications.  Maybe then people would pay attention to the end user license agreements (EULAs).

Validating JSON against schema in PHP

GitHub was rather slow yesterday, which affected the speed of installing composer dependencies (since most of them are hosted on GitHub anyway).  Staring at a slowly scrolling list of installed dependencies, I noticed something interesting.

...
  - Installing seld/jsonlint (1.6.0)
  - Installing justinrainbow/json-schema (5.1.0)
...

Of course, I’ve heard of the seld/jsonlint before.  It’s a port of zaach/jsonlint JavaScript tool to PHP, written by Jordi Boggiano, aka Seldaek, the genius who brought us composer dependency manager and packagist.org repository.

But JSON schema? What’s that?

The last time I heard the word “schema” in a non-database context, it was in the XML domain.  And I hate XML with passion.  It’s ugly and horrible and should die a quick death.  The sooner, the better.

But with all its ugliness, XML has does something right – it allows the schema definition, against which the XML file can be validated later.

Can I have the same with JSON?  Well, apparently, yes!

justinrainbow/json-schema package allows one to define a schema for what’s allowed in the JSON file, and than validate against it.  And even more than that – it supports both required values and default values too.

Seeing the package being installed right next to something by Seldaek, I figured, composer might be using it already.  A quick look in the repository confirmed my suspicion.  Composer documentation provides more information, and links to an even more helpful JSON-Schema.org.

Mind.  Officially.  Blown.

At work, we use a whole lot of configuration files for many of our projects.  Those files which are intended for tech-savvy users, are usually in JSON or PHP format, without much validation attached to them.   Those files which are for non-technical users, usually rely on even simpler formats like INI and CSV.  I see this all changing and improving soon.

But before any of that happens, I need to play around with these amazing tools.  Here’s a quick first look that I did:

  1. Install the JSON validator: composer require justinrainbow/json-schema
  2. Create an example config.json file that I will be validating.
  3. Create a simple schema.json file that defines what is valid.
  4. Create a simple index.php file to tie it altogether, mostly just coping code from the documentation.

My config.json file looks like this:

{
	"blah": "foobar",
	"foo": "bar"
}

My schema.json file looks like this:

{
	"type": "object",
	"properties": {
		"blah": {
			"type": "string"
		},
		"version": {
			"type": "string",
			"default": "v1.0.0"
		}
	}
}

And, finally, my index.php file looks like this:

<?php
require_once 'vendor/autoload.php';

use JsonSchema\Validator;
use JsonSchema\Constraints\Constraint;

$config = json_decode(file_get_contents('config.json'));
$validator = new Validator; $validator->validate(
	$config,
	(object)['$ref' => 'file://' . realpath('schema.json')],
	Constraint::CHECK_MODE_APPLY_DEFAULTS
);

if ($validator->isValid()) {
	echo "JSON validates OK\n";
} else {
	echo "JSON validation errors:\n";
	foreach ($validator->getErrors() as $error) {
		print_r($error);
	}
}

print "\nResulting config:\n";
print_r($config);

When I run it, I get the following output:

$ php index.php 
JSON validates OK

Resulting config:
stdClass Object
(
    [blah] => foobar
    [foo] => bar
    [version] => v1.0.0
)

What if I change my config.json to have something invalid, like an integer instead of a string?

{
	"blah": 1,
	"foo": "bar"
}

The validation fails with a helpful information:

$ php index.php 
JSON validation errors:
Array
(
    [property] => blah
    [pointer] => /blah
    [message] => Integer value found, but a string is required
    [constraint] => type
)

Resulting config:
stdClass Object
(
    [blah] => 1
    [foo] => bar
    [version] => v1.0.0
)

This is great. Maybe even beyond great!

The possibilities here are endless.  First of all, we can obviously validate the configuration files.  Secondly, we can automatically generate the documentation for the supported configuration options and values.  It’s probably not going to be super fantastic at first, but it will cover ALL supported cases and will always be up-to-date.  Thirdly, this whole thing can be taken to the next level very easily, since the schema files are JSON themselves, which means schema’s can be generated on the fly.

For example, in our projects, we allow the admin/developer to specify which database field of a table is used as display field (in links and such).  Only existing database fields should be allowed.  So, we can generate the schema with available fields on project deployment, and then validate the user configuration against his particular database setup.

There are probably even better ways to utilize all this, but I’ll have to think about it, which is not easy with the mind blown…

Update (March 16, 2017): also have a look at some alternative JSON Schema validators.  JSON Guard might be a slightly better option.

My lightbulb moment with modular design

Cameron Lock, of Yammer fame, describes the complexities involved that led her and the team to a simpler, more modular approach to the mobile application design.  The most important bit after grouping everything into modules, practically, I think, is this:

We stopped defining margins between modules. Instead, all the spacing in the app would come from padding within the modules — specifically, top padding. Bottom padding would have worked, too; just not both. The key is to choose one of the two and stick with it.

awless – a Mighty CLI for AWS

awless is a command line interface to the Amazon AWS.  While Amazon AWS already has its own set of tools for command line interface, awless makes things even simpler, with the following features:

  • run frequent actions by using simple commands
  • easily explore your infrastructure and cloud resources inter relations via CLI
  • ensure smart defaults & security best practices
  • manage resources through robust runnable & scriptable templates (see awless templates)
  • explore, analyse and query your infrastructure offline
  • explore, analyse and query your infrastructure through time