snippets

Multisite Apache Solr Search with Domain Access

Using one Apache Solr search core with more than one Drupal website isn't too difficult; you simply use a module like Apache Solr Multisite Search, or a technique like the one mentioned in Nick Veenhof's post, Let's talk Apache Solr Multisite. This kind of technique can save you time (and even money!) so you can use one Hosted Apache Solr subscription with multiple sites. The only caveat: any site using the solr core could see any other site's content (which shouldn't be a problem if you control all the sites and don't expose private data through solr).

There are two ways to make Apache Solr Search Integration work with Domain Access (one of which works similarly to the methods mentioned above for multisite), and which method you use depends on how your site's content is structured.

Filter/Search on multiple fields with Views 3.x

[Update: As of Views 7.x-3.4, you can now use the new "Global: Combine fields filter" to combine fields for an exposed search. Just add the fields you want to search to the view's Fields section, then add a 'Global: Combine fields filter' and select all the fields you want to search. Simple as that!]


A common need I run into with a ton of Drupal sites and Views is searching/filtering content based on multiple fields. For example, a lot of people would like to search for content using either the Title or the Body for a particular content type.

There are two primary solutions offered for this situation, but they both have downsides or are overly complex, in my opinion:

  • Use the Computed Field module to create yet another field stored in the database, combining the two (or more) fields you want to search, then expose a filter for that field instead of both of the individual fields. (I don't like this because it duplicates content/storage, and involves an extra module to do so).
  • Use the Views Filters Populate to invisibly populate a second field that you've added to a views OR group (using Views OR in Views 2.x, or the built-in AND/OR functionality in Views 3.x). (This module is slightly limited in that you can only work with strings, and again, it involves an extra module).

Instead of using an extra module, I simply do the following to achieve a multi-field search:

Finding an Image's width/height dimensions using JavaScript

For a complex Drupal node form I've been working on for flocknote, I have a relatively complicated image switching functionality that lets people change an imagefield on the node (either when creating a new one or editing an existing node), and once the imagefield is changed, some custom jQuery code will grab that image and display it in the form, for a very WYSWIYG-like experience (the node looks almost exactly the same when editing/adding as it does once the user saves the node).

One problem is that images can be arbitrarily high (though they're resized to 600px wide), and I can't easily get the height of the image through any traditional means. If I were grabbing an already-saved imagefield image, I could throw the image height into the JS settings for the page. However, getting a dynamically-added image's height/width values is surprisingly tricky using JavaScript, at least if you take a look around the web and try using many people's suggestions (which work great if the image was already loaded with the page's content, but not if the image is dynamically added, or if the image hasn't yet loaded on the page.

Getting Ping statistics with PHP

[Note: Since writing this post, I've created the Ping class for PHP, which incorporates three different ping/latency/uptime methods for PHP, and is a lot more robust than the script I have posted below.]

I recently needed to display some ping/server statistics on a website using PHP. The simplest way to do something like this is to use the built-in linux utility ping, and then parse the results. Instead of doing complex regex with the entirety of ping's output, though, I also used a couple other built-in linux utilities to get just what I needed.

Here's how I got just the response time of a given IP address:

<?php
 
<br /
?>
$ip_address = '123.456.789.0'; // IP address you'd like to ping.
exec("ping -c 1 " . $ip_address . " | head -n 2 | tail -n 1 | awk '{print $7}'", $ping_time);
print $ping_time[0]; // First item in array, since exec returns an array.
?>

The above script will ping the given IP address, and simply pull out the response time in milliseconds. You can further parse the response time to just be the numeric value by running it through substr($ping_time[0], 5).

Moving Comments into a Block - Drupal 7

[Note: It looks like there's a new module, as of January 2013, Node Comment Block, which uses the technique outlined below to move comments into a block.]

Most of the time, Drupal's convention of printing comments and the comment form inside the node template (node.tpl.php) is desirable, and doesn't cause any headaches.

However, I've had a few cases where I wanted to either put comments and the comment form in another place on the page, and in the most recent case, I asked around to see what people recommended for moving comments out of the normal rendering method. I found a few mentions of using Panels, and also noticed the Commentsblock module that does something like this using Views.

However, I just wanted to grab the normal comment information, and stick it directly into a block, and put that block somewhere else. I didn't want Views' overhead, or to have to re-theme and tweak things in Views, since I already have a firm grasp of comment rendering and form theming with the core comment display.

So, I set out to do something similar to this comment on drupal.org (which was also suggested by Jimajamma on Drupal Answers).

Sending emails to multiple receipients with Amazon SES

After reading through a ton of documentation posts and forum topics for Amazon SES about this issue, I finally found this post about the string list format that helped me be able to send an email with Amazon SES's sendmail API to multiple recipients.

Every way I tried getting this working, I was receiving errors like InvalidParameter for the sender, Unexpected list element termination for the error code, etc.

Normally, when sending email, you can either pass a single address or multiple addresses as a string, and you'll be fine:

Using apachebench (ab) with Drupal 7 to load test site with authenticated users

apachebench is an excellent performance and load-testing tool for any website, and Drupal-based sites are no exception. A lot of Drupal sites, though, need to be measured not only under heavy anonymous traffic load (users who aren't logged in), but also under heavy authenticated-user load.

Drupal.org has some good tips for ab testing, but the details for using ab's '-C' option (notice the capital C... C is for Cookie) are lacking. Basically, if you pass the -C option with a valid session ID/cookie, Drupal will send ab the page as if ab were authenticated.

Instead of constantly going into the database and looking up session IDs and such nonsense, I have a simple script, which is quite revised from the 2008-era script originally from 2bits that worked with Drupal 5, which will give you the proper ab commands for stress-testing your Drupal site under authenticated user load. Simply copy the attached script (source pasted below) to your site's docroot, and run the command from the command line as follows:

Changing RSS Feed item links (and other data) in Drupal 7

You can do a lot of great things with field display in Drupal 7's 'manage display' tab for a content type. You can control the order and label position of each field attached to a node type in that tab for Full node displays, Teasers, and RSS displays (or other displays you set up).

However, there's no way to change certain aspects of a node's display inside an RSS Feed, such as the 'creator' tag, the 'link' tag, or the 'title' tag. For a news aggregation site I run, I wanted to modify the

<br />
<link />
tag when displaying 'story' nodes, and make the link tag give an absolute URL to the original source instead of to my drupal site (so, instead of http://www.mysite.com/node/12, it would go to http://www.example.com/original-story-url).

A lot of blogs also use this kind of format for reposted blog items (such as Daring Fireball), so users go straight to the source when they click on the title of an item in their RSS reader of choice. My method below can be modified to conditionally change a link if a field has a value (say, a 'RSS absolute URL' field or something like that).

Prefill the Subject of a Privatemsg Message

I've had a nice go at making private messaging capabilities for flockNote work a lot nicer than the out-of-the-box Privatemsg module experience, by simplifying everything to the point that it's closer to the Facebook Direct Message system than the normal Privatemsg UX. (Privatemsg is the premiere way of handling private messaging in Drupal. It's already awesome out of the box... just needed a bit more help for our particular site ;-).

One thing I had wanted to do for a while is prefill the subject field of certain messages. I already have the new private message page appear inside an overlay popup after a user clicks on a link to send a private message to another user on the site.

Privatemsg prefill subject