Tutorials

This is your moment, you've decided to step up and make a job board for your local Drupal User Group. You spend some time thinking about everything you'll need, including the job listings themselves. You'll want to gather the standard info, like job title and job description, salary, experience, the works. When it comes to gathering company info, your instincts make you take a few extra moments to plan.

If you think about this from the perspective of the person posting 6 or 7 jobs, she would end up having to type (or at least copy and paste) the business' contact information each time. If you think about collecting 3 or 4 fields for each business, then that's about 20 extra form fields for the user to fill out. If she then decides to change the info, let's say she made a typo, she now must click through each edit screen 6 or 7 times. That amounts to hundreds of clicks and several hundred repeated keystrokes.

There must be a better way. A nodereference can help your users.

Once finished, you will have two nodes, one for a job and another for a company, and yet you will still display the information about the company inside the job listing.

By the end of this tutorial, you should understand what a nodereference is for, how to create and use one, and finally, how to use template files to theme the output of the nodereference and get the most out of the relationship.

This article is also available in French from KolossalDrupal.

There's an incredible amount of functionality that can be provided by the Views module, especially when it is combined with intelligent use of Node Reference fields. When you relate your site's nodes with Node Reference fields, these relationships can be easily leveraged to create some very useful views.

I'm going to build a view for a sample music site. In the site, I have 3 related content types for "Band" nodes ("Black Eyed Peas", "Linkin Park", etc...), "Album" nodes ("Back in Black", "Bat Out of Hell", etc...), and "Events" (concerts, television appearances, etc...)

If you've read the first couple of installments of this series, you should have a pretty good idea of what the "semantic web" is by now. By providing precise meaning to a site's content, applications can take advantage of these machine-readable hints to link data together across sites in a myraid of ways. Before you jump in the deep end of the semantic web pool, there's a few more things you should have a clear understanding of.

As I previously defined, RDF stands for Resource Description Framework. This is a family of standards for describing content on the web. The vast majority of current and future Drupal implementations of RDF are actually RDFa (Resource Description Framework in Attributes), a set of extensions to XHTML. RDF is normally implemented using XML; while this is possible with Drupal, RDFa allows Drupal to implement RDF as part of the standard content displays.

It could have been an April Fools joke.  On April 1st we got the call. "We have mockups for the design of the site, and we need the theme done in 2 weeks. After that we can discuss the XML import part of the project. We need to go live at the beginning of May."  We knew it would be a challenge, but we made it happen - on May 7th the site went live.

Sometimes in our lives, we all have pain, we all have sorrow. And sometimes we also have to launch Drupal sites into the wild blue yonder. It's during these times that we separate the grown-ups from the n00bs, and we see how well our site performs under heavy load. Many of us didn't need to worry about speed, page size, and server load in our younger years when we were building sites for Uncle Don and Aunt Sue, but eventually you get that big client, and you need some help.

Testing your site's performance

There are several ways to test, and a few metrics to acquaint yourself with. Not all metrics are created equal, but all of them are important at one time or other. In Part I of this post, you will be reading about testing with the Apache Benchmark tool on the command line.

Keeping a site's design as clean as possible is something all (well, okay, maybe not "all") designers and developers strive for. One relatively easy thing that you can do towards this goal is removing the supporting (and often unnecessary) text around your site's search field. I'm talking about the "Enter search terms" or "Search this site" text that floats innocently above or next to the text input box. Is this really necessary? I don't think so.

A much cleaner way of presenting a search box is with some default text inside the input field that automatically disappears when the user moves the cursor into the field.

Ubercart is arguably the leading ecommerce module suite for Drupal. It allows site admins to sell virtually just about anything online, including physical products, downloadable products, and event admissions. Often, when selling event admissions, it is desirable for the registrant to be able to fill out a profile during the checkout process that can be posted on the site once the transaction is complete. The UC Node Checkout module was built for this purpose. This is the way last year's Do It With Drupal conference handled registrations - with these exact modules.

Setting it up can be a little tricky, as it is not entirely a straight-forward process. Ryan Szrama, the de-facto leader of the Ubercart project, demoed this module during the recent DrupalCon DC. I thought I'd take the time to reproduce what Ryan did, as it is a great introduction to this module. Keep in mind it won't be an exact reproduction, but it should be pretty close.

This article will assume you're familiar with some very basic Ubercart concepts, if you're not, don't worry, this isn't rocket science. One thing you'll need to do if you're playing along at home is to create the "keys" directory for test credit card payments - full info on this is located at admin/store/settings/payment/edit/methods in your Drupal install (assuming you already have Ubercart enabled).

This article is also available in French.

Displaying hierarchical content is a common request of database-driven web sites. Drupal gives you great flexibility in doing this without writing a single line of code, using a couple of battle-tested modules. As an example, let's say you're building an automotive web site. Your site is going to have a list of automotive brands and the vehicles they build. You'd like to only have to enter each brand's information into the database once, then simply refer to that brand whenever you add one of their vehicles to the site. In this example, I have 2 brands, Chevy and Jeep, and each brand has 3 vehicles.

Drupal's powerful CCK module allows you to define different content types for your web site. The Node Reference module, included with the rest of CCK, allows you to set up hierarchical relationships between content types.

The "summary" list is Views is a really handy feature, but unless it is properly configured, it can lead to an inconsistent experience for end-users. The goal of this post is to demonstrate how a little bit of configuration can provide a very consistent user experience.

Here's a quick example of what I'm trying to avoid: consider the following content type called, "Food":

As you can see, it is a very simple content type, with only a single added field, "field_food_type". This text field is set up to require the user to select one of its options.

When creating a view to show all "Food" nodes, there might be too many to display all at once - you'd like to break up the view by food type in order to allow the user to drill down to the food they're looking for. Using a single Views 2 "Page" display, this is easy to do - just add an argument for the food type and have it display a summary when no argument is present:

This will result in the showing only the food types when the page is displayed with no arguments:

When one of the food types is clicked on, you'll see a list of matching foods:

This works great and is easy to set up if this is what you're looking for. However, I find that often I'd like the summary and a listing of matching content to be displayed at all times. When there is no argument present, then I want a paged list of all the content as well as the summary. When an argument is present, I want the filtered content but I still also want the summary. This can be quite easily done using a display attachment.

Looks like some MySQL data export/import operations can fail for anonymous users. I just did a data dump from my local development server to the live site and all the comments by users who aren't logged in were not showing up. Gone. Missing. It turns out MySQL was trying to stick the autoincrement value in the `uid` field in the place of the supplied `0`.

One of the most frustrating things about Drupal's current architecture is that comments, and the form to post them, are attached to nodes and don't easily allow you to move them around in your TPL files. There really should be an easier way to just place them anywhere you'd like. Most times this doesn't get in your way, until you want to do some fancy layouts where your content is split into multiple columns on the page.

If you're like me, most of your projects are redesigns of existing sites. And if the site is already on some kind of CMS, this means importing content from the old system into Drupal, and to make it easy you'll do it with MySQL directly.

There are pros and cons about this approach, which I am learning, and one of the cons is that content created by the database may not always get plugged into all of Drupal's various tables. Sure, you got the text into node, node_revisions, can your CCK tables, but there is more than meets the eye.

Today's challenge: your editors just handed you almost 200 taxonomy terms to add to the site, and you don't have the time or inclination to hit the taxonomy/n/add/term page for the next 2 hours or so... AWK to the rescue!

Doing a simple CSV export of the term_data and term_hierarchy tables, you've got a pretty simple structure:

term_data
tid,vid,name,description,weight

term_hierarchy
tid,parent

What you'll ultimately generate here is a file that stores everything you need to know about importing these terms via a CSV - the term names, the weights, good IDs, and the TID of the parents.

2048,#the current value of the sequences for term_data
term,34,Blogs,#a helper line
x,1,Drupal,All about Drupal,-5
x,1,Modules,Ways to extend Drupal,-4
x,1,Themes,Making your install pretty,-3
term,35,News,#a second helper line
x,1,International,,0
x,1,Local,,0
x,1,Hyperlocal,,0

In this file, we've got 3 types of data:

1. The starting value for sequences
2. The id of the parent term for the next several rows, starting with the word "term" followed by the TID and the plain English name just to help us get organized
3. The new terms, with an "x" where the new TIDs will be placed, and the VID, Description and Weight all filled out.

In my previous post, I talked about how I implemented the dynamic marker system on OffRoadAtlas.com. In this post, I'll cover the functionality that the PdMarker adds to the site.

I recently upgraded OffRoadAtlas.com with a custom map interface based on the GMap module. I was able to do this while leaving the GMap module is virtually un-hacked (with the exception of modifying the "GMAP_API_VERSION" variable) - all of the customizations were made via an additional "helper" module that was written specifically for this site.