In this tutorial, I'll share my notes and code I've used to setup geospatial Apache Solr searching in Drupal 7 using the Search API module. For this tutorial I created a minimal Ubuntu server virtual machine. All the commands should be executed as a user with permission to modify files, or prefixed with "sudo".

The first thing I do with a fresh virtual machine is check for package upgrades.

I find it cumbersome to type in a virtual machine window, so I'll install open-ssh and ssh from my Mac. If you plan to do so, you'll need to find your virtual machine's IP address using ifconfig. For this tutorial I added local DNS (/etc/hosts) to point "drupal7.vm" to my VM's IP.

Install the LAMP stack. The following packages will install Apache httpd as a dependency.

At this point, browsing to your VM/server's IP address will give you the standard Apache welcome message:
It works!
This is the default web page for this server.
The web server software is running but no content has been added, yet.

Install version control.

Create a mysql database for Drupal 7.

Install drush via Pear.

Verifying drush is installed.

Create an Apache vhost directory

Download drupal via drush

Integrate drupal file system with git

Install drupal via drush

Add Apache2 vhost

At this point, browsing to your VM/server's hostname should show a Drupal installation.

Part 2, Tomcat/Solr

Installing java jdk and tomcat6

Browsing to your VM/server's hostname on port 8080 (ex: http://drupal7.vm:8080) will show the generic Tomcat welcome message:
It works !
If you're seeing this page via a web browser, it means you've setup Tomcat successfully. Congratulations!

Installing Solr in Tomcat

Copy/rename java war file into Tomcat webapps directory

Note: copying the java war file into the Tomcat webapps folder will create this directory automatically:

Copy solr files

Create Catalina config file to link war file to solr directory

Setup Tomcat admin user(s)

Update webapps WEB-INF/web.xml file

Download search api drupal modules that contain solr xml configuration files, and copy into solr conf directory

Reset tomcat permissions, and restart tomcat

You should now be able to browse to the solr admin java page.
Example: http://drupal7.vm:8080/solr/admin/

If things aren't working well at this point, check the Tomcat logs and look for SEVERE log entries

In addition, the solr java module should be listed in the Tomcat Web Application Manager
Ex URL: http://drupal7.vm:8080/manager/html

Part 3, Drupal code

Getting the solr-php-client library from code.google.com

Downloading and installing contrib drupal modules

(Optionally) I install devel, admin_menu, and disable overlay/toolbar

Add the tomcat/solr server to Search API configuration.
- URL: /admin/config/search/search_api
- click on "+ Add Server"
- server name: Solr 3.5.0
- Service class: Solr service
- Solr host: localhost
- Solr port: 8080
- Solr path: /solr
- click Create Server

You should receive some confirmation messages:
The server was successfully created.
The Solr server could be reached (latency: # ms).
If not, ensure tomcat/solr is reachable at the url you specified and the tomcat service is running.

At this point Solr is ready to send/receive data and index content, but there is nothing to index. For this tutorial, I decided to build off of user profiles and store latitude and longitude using the geolocation field module.

Adding some user profile fields:
- URL: /admin/config/people/accounts/fields
- First Name | field_name_first | Text
- Last Name | field_name_last | Text
- Geolocation | field_geolocation | Geolocation | Latitude/Longitude

I then added a bunch of users with latitude/longitude coordinates.
- URL: /admin/people/create
- note: I used Google Geocoding API to fetch the coordinates: http://code.google.com/apis/maps/documentation/geocoding/

Adding the search api index.
- URL: /admin/config/search/search_api
- click "+ Add index"
- Index name: People
- Item type: User
- Server: Solr 3.5.0
- click: Create Index

On the next admin page, you can select which fields to index. For this tutorial, I chose: User ID, Name, Email, URL, First Name, and Last Name. Unfortunately, at the time of writing this, the geolocation lat/lng fields are not exposed to the Entity API. I assume this is a temporary problem, and there are numerous patches in the geolocation issue queue.
@see (for example):
Property Info callback for Entity API - http://drupal.org/node/1366642
Fix for Search API not picking up the entity to index it's fields - http://drupal.org/node/1320564

I copied code directly from the issues queue, made some modifications, and created a custom module to expose the geolocation field data to the entity api module. In addition, I added a new property "lat_lon" that concatenates lat and lng together with a comma. @see: http://wiki.apache.org/solr/SpatialSearch

I added this code to a custom module, renamed function calls (as necessary), and enabled. Update the solr index to add the new fields to the index.
- URL: /admin/config/search/search_api/index/people/fields
- Expand "Add Related Fields"
- Choose Geolocation, click Add fields
The above will expose the following fields now available to the index:
- Geolocation » Latitude
- Geolocation » Longitude
- Geolocation » Sine of Latitude
- Geolocation » Cosine of Latitude
- Geolocation » Radian Latitude
- Geolocation » Latitude,Longitude
Enable "Geolocation » Latitude,Longitude" and save changes.

Index the content.
- URL: /admin/config/search/search_api/index/people/status
- Click: Index now
- note: if you had already indexed the content, you'll probably need to clear it first
In my environment, I got the following confirmation message:
Successfully indexed 7 items.

I find it to be very helpful to verify the xml response from Solr directly after making changes to the index/schema.
The following URL structure will query solr for all results and return all fields:

A sample XML document response.

Take note the field name in the following XML, it is used in the next file edit.

Update the solr schema.xml configuration and add the geospatial fieldType and field data.

Restart Tomcat

Since the schema and solr data types have been updated, the content will have to be re-indexed.
- URL: /admin/config/search/search_api/index/people/status
- click: Clear index
- click: Index now

Returning to the solr query above will now show updated xml: (note: no longer an array)

Verify the native solr geospatial searching is working using the following query syntax:
URL: http://drupal7.vm:8080/solr/select/?q=&fl=*&fq={!geofilt sfield=t_field_geolocation:lat_lon pt=42.933692,-72.278141 d=100}
By putting a distance parameter of 100 (kilometers) and Nashua NH coordinates, I get 2 results: Nashua and Portsmouth, awesome.

Create a solr integrated view.
- URL: /admin/structure/views/add
- View name: People
- Show: People
- Create a Page [checked]
- Path: people
- Continue & edit
Note: at this point, you have full reign over view configuration. For this tutorial, I set the format to Grid, and added some fields:
- Geolocation: Latitude,Longitude (indexed)
- Indexed User: Email
- Indexed User: First Name
- Indexed User: Last Name
- Indexed User: Name
Save the view when edits are complete.

Browsing to the view will show something like this:
Ex URL: http://drupal7.vm.people

The next chunk of custom code modifies the solr query executed and adds geospatial filtering.
@see: hook_search_api_solr_query_alter(array &$call_args, SearchApiQueryInterface $query)

The above code will limit the view's results using the hardcoded coordinates.

Clearly, it works but there are loose ends to tie..
- automatically fetch a user's coordinates to store in the geolocation field
- add a search form to the people view page to allow the user to search for a location (instead of hard coded coordinates, blah)
- translate the user's location search input to coordinates using an API

Hopefully, I can find more time to elaborate on this tutorial in the near future! Cheers.

Recently I was working on a project that had a view with an exposed filter for country (via location module) and the dropdown list by default showed the entire country list, which was very large. I decided to write a code snippet that would reduce the select options to show only the countries that have been assigned to the nodes.

In my sandbox, I create a simple node type for "person" that used the location module to capture the user's country. I then created a view to show the people's names and countries, and added an exposed filter for country.

Clicking on the exposed filter showed all of the available countries, which was a very large list.

I added the following code to my module to alter the exposed filter form and reduce the country list. (Please note, an alternative approach would be to modify the views object, I wanted to show how this could be accomplished in hook_form_alter())

Now the view only shows countries that match the resulting nodes.

In this blog entry I'll show how you can create a Google map showing where your users are located using CCK, Content Profile, Views, GMap, and Location modules. Once you've downloaded and extracted those modules, enable the following modules (and set permissions accordingly):

Next you'll need to configure these new modules. On the GMap settings page (admin/settings/gmap) you'll need to add your API Key and enable the setting to Use AutoZoom. On the Location settings page (admin/settings/location) enable the checkbox to use a Google Map to set latitude and longitude and enable JIT geocoding. On the geocoding settings page (admin/settings/location/geocoding), you'll have to enable Google Maps for the desired countries.

The Content Profile module creates a new content type called "Profile". You'll need to add a new field to this content type for the user's location (admin/content/node-type/profile/fields). Enter a label for the node type (Location), enter a field name (field_location), choose "Location" for the field type, and choose "Location Field" for the widget.

On the next screen edit the Locative information sections (Collection and Display) to your liking, and save the field settings. For my example, I enabled Street location, Additional, City, State, Postal code, Country, and Coordinate Chooser.

Now if you create your profile node (node/add/profile) you can enter your location information and save the new node. If all is working at this point, if you return to the profile node edit screen and scroll down to the location information, you should now see a marker on map for your location and the geocoded information will be shown.

Now you can add a new view (admin/build/views/add) to show the user's profile locations. Enter a name for your view, choose node for the view type, and click the next button. Add a new filter for "Node: Published" is true and "Node: Type" is one of "Profile". Add a new relationship for Content: Location (field_location). Add fields for "Location: Latitude" (using the Location relationship), "Location: Longitude" (using the Location relationship), and any additional fields you'd like to display in the GMap marker (title, parts of the address, etc). For the Style of the view choose "GMap". For the GMap style settings, select "Choose latitude and longitude fields" for the Data Source and ensure the Latitude and Longitude fields as set.

Lastly, I added a page view so I could see the results in action..

ps> special thanks to everyone at CommonPlaces for their great technical discussions about these modules!

The Fivestar module offers a great way to allow users to rate your content. Enabling this functionality for a node type was straight forward. My next goal was to show the fivestar widget in a view for each node row. Unfortunately, the row styling for my view was "Fields", so the fivestar widget would not appear. Apparently, the fivestar widget is only available for the teaser & full node display options.

No worries, you can always override the themable output of a view. Using the "Theme information" section on the view edit screen, I decided to create a new template file in my theme directory for "Row style output". For example:

I then copied the contents of default view template into this file.

By examining the hook_nodeapi() function of the Fivestar module, I decided to use the fivestar_widget_form() function to embed the widget in my view. This function accepts one argument, the $node object. Inside the first php tag in my new template file, I added the following code to load the node object:

Last, I determined a good insertion point for the fivestar widget in this template file, and added the following code:

If done correctly the Fivestar widget should now be embedded in the view for each node row.

In this tutorial I'll show how I integrated Open Flash Charts into a Drupal view to create a fancy flash based chart from CCK node data.

Let's start by creating a new CCK node type to contain the data. I called mine "graph_data".

I added an integer field called "field_data".

I created a bunch of nodes, populating them with a random integer from 0 to 100.

I added a view called "Graph" to show all of my data. I filtered by node type and published, added sort criteria, chose "Unformatted" for Style, chose how many items to show (100), and added a page view.

At this point, you'll need to download and incorporate the Open Flash Charts library. You can download the library here or by visiting their website and clicking on Downloads in the top right. Uncompress the download and copy the entire directory (version-2-ichor) into your theme directory.

Sample directory structure:

I created a new file in my theme directory called "views-view-unformatted--Graph.tpl.php" (see: Theme Information section on the View edit page) to override it's output. I put the guts of my code in this file:

Here's a screenshot of my new flash integrated view