Boulder Information Services Blog

I have an application with deeply nested models. I want to select several specific fields from a multi-layered “slice” of the data. And since we’re using CakePHP, I want to use Cake’s methods rather than writing my own custom query. How do I do this?

Let’s get specific with a look at the nested data. I need data from three models: PayStub, Employee, and Employer. The relationship goes like this:

• PayStub belongs to
• Employee belongs to
• Employer

Here’s the TL;DR of this post:

<?php
$this->records = $this->PayStub->find('all', array(
	'contain' => [
		'Employee' => [
			'fields' => [
				'first_name',
				'employer_id',
			],
			'Employer' => [
				'fields' => [
					'id',
					'first_name'
				]
			]
		]
	],
	'conditions' => array(
		'period_ending' => $end_date
	),
	'fields' => array(
		'PayStub.net',
		'PayStub.period_ending',
	),
	'recursive' => -1
	)
);

So why is that so difficult? Let’s back up and look at the joined (but not chained) query to see where my expectations about Cake’s behavior came from. Here’s a query that only joins 2 models — PayStub and Employee. This query works just fine and returns joined data as expected.

<?php
$this->records = $this->PayStub->find('all', array(
		'conditions' => array(
			'period_ending' => $end_date
		),
		'fields' => array(
			'PayStub.net',
			'PayStub.period_ending',
			'Employee.first_name',
		),
		'recursive' => 0
	)
);

So when I wanted to join another table to the query, here’s the first change I made:

<?php
$this->records = $this->PayStub->find('all', array(
		'conditions' => array(
			'period_ending' => $end_date
		),
		'fields' => array(
			'PayStub.net',
			'PayStub.period_ending',
			'Employee.first_name',
			'Employer.first_name', // <- Dot notation? Great, I'll try this		
		),
		'recursive' => 0
	)
);

Clearly that didn’t work, and I suspected that I would need to explicitly use Cake’s containable behavior. But it took me several tries before I found the right syntax for chaining containables. Here are my early attempts, in the absence of a specific, simple example on the CakePHP documentation site.

'contain' => ['Employee', 'Employer']; 
'contain' => ['Employee', 'Employee.Employer'];

Ah, but here’s the correct way to do it:

'contain' => ['Employee' => ['Employer']]

Fine, but now I wanted to limit the fields coming back from each model. Again, my initial guesses were not stupid, but they were wrong:

'fields' => array(
	'PayStub.net',
	'Employee.first_name',
	'Employer.first_name', // <- Works if you take out this line
),

'fields' => array(
	'PayStub.net',
	'Employee.first_name',
	'Employee.Employer.first_name', // <- Still nope. Only works on first join
),

Well, it turns out that the contain clause can contain fields. Here’s the right way to contain Employer‘s fields:

'contain' => ['Employee' => ['Employer' => ['fields' => 'first_name']]],
'fields' => array(
	'PayStub.net',
	'Employee.first_name',
),

I dislike this because to restrict the fields, I need to do it two different places. So I thought I’d combine them and make the whole query consistent. Spoiler alert: this does not work:

'contain' => [
	'fields' => 'net',
	'Employee' => [
		'fields' => 'first_name'
		'Employer' => [
			'fields' => 'first_name'
		]
	]
],

It turns out the first join, Employee, really can define its fields in two places: either in the contain array, or in the fields array using dot notation. In other words, these are equivalent:

'contain' => [
	'Employee' => [
		'fields' => 'first_name'
	]
],
...

and

...
'fields' => [
	'PayStub.net'
	'Employee.first_name'
]

But the only place you can defined the fields for the primary table, PayStub, is in the fields array — not in any sort of contain array.

CakePHP has infrastructure to remove tables created in the test database as fixtures. The documentation implies that these tables will be removed as part of the test cleanup. But it is not happening. Here is where it fails. This class is CakeTestRunner

The fixture manager would remove the tables at $fixture->shutdown(); but it’s not happening because the line above calls doRun without passing false as the third parameter. Therefore, doRun exits and the fixtures are never removed. And because the third parameter is missing — that is, because it is is not surfaced to my own code — it cannot be overridden.

Not sure if this is a bug or a feature or … ?

You have to “reissue” the certificate. First step is to create a new Certificate Signing Request (CSR) on the host. CPanel allows you to put multiple domains on the CSR, and that’s how you add a new domain to an existing certificate.

Next step is to “reissue” the certificate. I used Namecheap, and the instructions for getting to “reissue” are here: https://www.namecheap.com/support/knowledgebase/article.aspx/811/70/how-do-i-reissue-my-ssl-certificate their screen shots are out of date. The “Domain list” page is here: https://ap.www.namecheap.com/Domains/DomainList

Then I verify my identity with Namecheap. There are different methods — email, HTTP, and DNS.

Eventually they issue a new certificate. I save the .zip file to my computer so that I can upload it to my host. CPanel has a section for SSL/TLS where I can upload new certificates, which I do.

CPanel wants a .crt file. It accepted the .zip I got from Namecheap, but it didn’t actually stick. so either upload the .crt or paste the text of the certificate instead.

“Hey, Mart, can you post the latest newsletter to my web site? By the way is that something I can do easily?”

I have many clients for whom I’ve built web sites. I usually try to let them make updates themselves through an admin interface, but even then, some clients would rather have me do the work.

For some people, updating their web site is about as fun and relevant to their job as filing taxes.

So what do you do when a client wants to be able to make changes to documents, or launch a blog, or post newsletters on their own web site?

WordPress to the Rescue (*assuming you drank the WP Kool-Aid)

I know many advocates of WordPress who say it’s just as easy to use as Word or Pages. They recommend it to all their clients. In fact, here I am on a WordPress site. And yet, I have a hard time recommending it for some of my clients, for many reasons:

• Interface overload can be intimidating for someone who just wants to publish some text. As I type I have a sidebar with 8 options; I see two icons above the sidebar that I don’t necessarily understand, as well as a few cryptic buttons. As a computer professional, I don’t find them intimidating, but to someone who doesn’t know what’s okay to ignore, it’s more cognitive load.
• WordPress requires an installation, of code and database.
• WordPress is popular among hackers and spammers — just the sort of security risk most of my clients don’t want to think about.
• WordPress doesn’t easily integrate with an existing design. Someone has to spend time customizing WordPress templates to sort-of match a site’s design.
• WordPress does HTML structure how it likes to which means your blog and your site may not look exactly the same, and they may not share CSS and JS, requiring twice the effort for every update.

Don’t Start with a Hammer

Some would say that WordPress is a great tool. But when your favorite tool is a hammer all your problems look like nails.

Rather than recommending yet another unnecessary WordPress installation, I asked, what is it that my “newsletter client” was already doing? And how can we painlessly integrate that into her web site.

Well, she had written a newsletter in Pages. There was minimal formatting — a headline, paragraphs, one link, and a photo. She created a document, pasted a photo and e-mailed it to  her friends.

Would there be some way to write a document, without all the overhead of WordPress, and include it on a web site?

Of course there is.

Markdown is Simple

One of the best experiences I had editing a document on a web site was submitting a correction to the CakePHP documentation. The documentation is hosted on github. When you find a page you want to edit, you click a button that opens the page’s Markdown source. You make whatever changes you like, then submit your version of the doc to be reviewed, merged, and published.

Because it’s markdown, you can’t inject any malicious code. You can’t ruin the structure or the design of the page. You can only add text, with basic formatting. So unless you type gibberish, you really can’t do much to break the site; you are just adding content.

WordPress’ HTML structure isn’t exactly “Simple”

Markdown’s resulting HTML is simple and clean, unlike what comes out of WordPress. It plays nice with whatever template and style sheet you’ve already defined.

For my client to save her newsletter as Markdown would be a simple matter of exporting her already-written document as plain text, and cleaning up three things –

• adding # before the headline,
• changing her link to [link text](url) format,
• and changing the photo to .

Uploading

If she creates an .md (markdown) text file, it’s still not on her web site. Should she FTP the file into a special folder? That sounds like as much trouble as WordPress with even more risk.

What about hosting the documents on github? Well, it’s a nice idea but their system is entirely set up for hosting documentation. It’s not really usable for ad-hoc web sites.

However, the idea of committing code to a repository and pushing it seems like it might be pretty easy, especially if we find a very user-friendly program like Tower or SourceTree. She doesn’t need to know about source code or how git works, she only needs to know that she checks in her new newsletter when its done, and clicks Push when she’s ready to launch. (We already have an auto-deploy script running). Fixing a typo is as simple as editing the document and re-pushing it.

I think it could be easier and cleaner and less risky than WordPress. But I admit this could be one of my crazy ideas that’s more dumb than inspired.

I’ll visit my client on Friday and show her both options. We’ll see what she thinks.