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Using something like CrossSlide is fine if you want fancy effects in your image translations, but for more simple effects you can use a single function to simply swap one image for another. First, lets create some simple markup that will allow us to display some images.

Wordpress allows administrators to change the number of posts that are printed out on a page at once on the page Settings - Reading. However, this also has an impact on the number of search results that Wordpress will display. In order to keep the size of the home page down many Wordpress admins will reduce the number of articles to two or three. This can instantly make search results with only a few results reach many pages.

To get around this you will need a template called search.php, this is the template that Wordpress will use when printing out the search results. Towards the top of this file (anywhere above The Loop) add the following code.

The other day I needed to copy a Drupal project from my source folder to another folder, so rather than manually copy the files I decided to create a Phing script that would do it for me in one go. This Phing script will export your Drupal project into another directory, change the database credentials and create zip and tar files of the project. The first thing to do is create a properties, here is the contents of that file.

When you run a phing script it will print things out to the console. These messages are either system messages (eg. BUILD STARTED) or echo messages that you have put into your build.xml file. All of this output is controlled and created by a logger file. The default logger is called (unsurprisingly) DefaultLogger and will be used as a default. There are a few different types of logger available, all of which can be found in the listener folder in your PEAR\phing directory.

To select a different logger script to be used just use the -logger flag in your phing call. To specify the DefaultLogger use the following:

phing -logger phing.listener.DefaultLogger

To specify an XML logger that will create an XML document of the phing events that occurred in the current working directory use the XmlLogger logger.

If you have been following the last four posts you should now have an application that will allow you to view and edit PDF metadata, extract the document contents for search indexing, and allow users to search that index.

The one final thing to do is to sort out what happens when any PDF metadata is changed. At the moment the application will allow us to change the metadata as much as we like, but these changes will not be replicated in our search index. In order to do this we have to fully re-index everything. This is obviously the wrong way to go about things, and the solution is quite simple. All we need to do is up the file controllers/PdfController.php and change the editmetaAction() method so that when the PDF metadata is saved, the search index is updated. Add the following code to the editmetaAction() method, just before the redirect.

Last time we had indexed our PDF documents and were ready to add a search form to our application. Adding search requires two things, the form to enter the search terms into and an action to control what happens when the form is submitted.

The easiest task is to set up the search view, create the view file search.phtml (in views/scripts/search/) and add the following code. This is just a basic form with a single text input. Note the addition of the queryString parameter, this will allow us to print out the last searched for value in the search box, which is good usability practice.

Last time we had reached the stage where we had PDF meta data and the extracted contents of PDF documents ready to be fed into our search indexing classes so that we can search them.

The first thing that is needed is a couple of configuration options to be set up. This will control where our Lucene index and the PDF files to be indexed will be kept. Add the following options to your configuration files (called application.ini if you used Zend Tool to create your applcation).

luceneIndex = \path\to\lucene\index
filesDirectory = \path\to\pdf\files\

Last time we looked at viewing and saving meta data to PDF documents using Zend Framework. The next step before we try to index them with Zend Lucene is to extract the data out of the documents themselves. I should note here that we can't extract the data perfectly from every PDF document, we certainly can't extract any images or tables from the PDF into any recognisable text. There is a little issue with extracting the text because we are essentially looking at compressed data. The text isn't saved into the document, it is rendered into the document using a font. So what we need to do is extract this data into some format the Lucene can tokenize. Because we are just getting the text out of the document for our search index we can take a few short-cuts in order to get as much textual data out of the document as possible. All of this data might not be fully readable and we will definitely loose any formatting and images, but for the purposes we are using it for we don't really need it. The idea is that we can retrieve as much relevant and indexable content for Zend Lucene to tokenize. Also, it is not possible to extract the data out of encrypted PDF documents.

Zend Lucene is a powerful search engine, but it does take a bit of setting up to get it working properly. One thing that I have had trouble getting up and running in the past is indexing and searching PDF documents. The difficulty here is that it isn't immediately apparent how you can index the contents of a PDF document with ease. I came across a couple of functions you can try out, but even if that doesn't work it is possible to create and edit PDF meta data using the Zend_Pdf library. Because there is a lot to cover on this subject I thought I would create a blog post in multiple parts. For this post I will be looking at how to add and edit this meta data. This meta data can be used to classify your PDF documents and allow you to index them and provide a decent search solution using Zend Lucene.

I'm not sure where I found this, but I have been using it on a few projects recently and it's helped a lot. It basically detects what system you are on and will give you a constant that keeps hold of the slash for that system.

if (strtoupper(substr(PHP_OS,0,3)) == 'WIN') {
 // Windows
 define('SLASH', '\\');
} else {
 // Linux/Unix 
 define('SLASH', '/');
}

For example, on a Windows system a file might be in C:\folders\data\, whereas on Linux the file would be in /folders/data/. So if you are given the full path as a string it can be difficult to separate the filename from the directory without knowing what system you are on.