Global search (GSoC2013)

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Global search
Project state	Community bonding period
Tracker issue	MDL-31989
Discussion	Writing Moodle's Global Search
Assignee	Prateek Sachan

GSOC '13

Introduction

Global Search will have the feature of searching keywords within the entire Moodle site across modules keeping the security intact.

It will display results based on relevance weightage.
Security will be preserved throughout the search.
Search Modules will enable chosen search engine integration with ease. Admins will have the option for selecting the modules that could be made "searchable"
It will include keywords from other files types (like PDFs, PPTs, HTML content and others).
Following are the features that I'm considering in implementing in the first version of Global Search:

Groupings of AND and OR. Eg.: ("query1" AND "query2") OR "query3"
Searching for phrases. Results with matched phrase will have higher priority and hence will be shown higher in the results.
Wildcard (*) (?) feature.
Stemming. Eg.: bag will return results both from bag and bags

Milestones

Writing cron jobs:(17th June - 21st June)
- Addition of records.
- Deletion of records.[shouldn't be focused upon just now]
- Update of records.
Design the solr schema and solconfig files. (22nd June - 26th June)
- These files will be embedded in the in a separate directory under the Global Search directory. Users will have to copy these two files to the Apache Solr example directory that they will download which will run the Solr jetty server. See Installation for more.
- schema.xml contains all the properties about the documents fields which are being indexed. There may be different fields pertaining to different modules.
- solrconfig.xml contains the configurational parameters for solr.
Writing the core search API for all searchable modules. (27th June - 3rd July)
- _SEARCH_ITERATOR($from=0)
- _SEARCH_DOCUMENTS($id)
- _SEARCH_ACCESS($id)
Adding proper security to the search API.(4th July - 8th July)
- Use of Access API
  - ACCESS_DENIED
  - ACCESS_GRANTED
- ACCESS_DELETED: Situations where the records may have been deleted-hence not viewable.
Reviewing the all the above once. (9th July - 10th July)
Integrating Apache Tika to handle indexing from external files (PDFs, PPTX etc.) (11th July - 13th July)
Writing the search functions for querying. (Just a basic search UI to be used at this moment). (14th July - 17th July)
- Input for query.
- Input for filter fields for filtering the search results.
- Input for AND/OR.
- Phrase searches.
- Stemming.
- Support for wildcards.
Admin page for search configuration options. (18th July - 27th July) (The UI page here will be the default type as being currently used. For example, Site Administration>Advance features)
- Start initial indexing. (When the admin will install Global Search into Moodle)
- Resume indexing. (If a previous indexing was paused).
- Deletion of entire index.
- Re-indexing.
- Deletion of index by specific modules only.(For example, only the index of records belonging to 'forum' module is to be deleted).
- configurational options for cron
  - Time of cron run.
Preparing for mid-term evaluation. (28th July - 1st August)
MID_TERM EVALUATION (2nd August)
Re-designing the search page. (2nd August - 7th August) (Taking ideas from community+discussion in forum)
Implementing the first prototype. (8th August - 15th August)
- Asking the community developers to test it.
  - Taking their guidance to optimize the code wherever possible.
  - Getting feedback.
Running Test cases and performance testing. (16th August - 21st August) (Performance testing will be good at this point as the code would have been optimized to some level as instructed by the developers above)
Debugging. (22nd August - 29th August)
Finalizing the Global Search documentation. (30th August - 6th September)
- Discussing it with my mentors whether everything has been properly covered or not.
Buffer Period. (7th September - 8th September)
- Making sure everything above has been implemented correctly and efficiently.
Submitting my code to Moodle and Google. (9th September - 15th September)
Suggested Pencils Down Period. (16th September)
Performing edits to the documentation after feedback from the Moodle community. (17th September - 22nd September)
Firm Pencils Down and Final Evaluation. (23rd September)

Installation

For using Global Search, users will have to install the PHP Solr PECL extension on server.

Following is the procedure for installing the extension in UNIX:

There are two dependencies of the extension:

CURL extension (libcurl 7.15.0 or later is required)
LIBXML extension (libxml2 2.6.26 or later is required)

Test whether the required extensions are installed or not by executing the following in a php file (Remember to delete the file as it has important information about your system):

echo phpinfo();

If the system does not have required versions of libcurl or libxml libraries, follow the steps given below. You will have to download the libraries

and compile them from source into a separate install prefix.

For libcurl:
wget http://curl.haxx.se/download/curl-7.19.6.tar.gz

tar -zxvf curl-7.19.6.tar.gz cd curl-7.19.6 sudo ./configure --prefix=/root/custom/software sudo make sudo make install

For libxml:
wget ftp://xmlsoft.org/libxml2/libxml2-2.7.6.tar.gz

tar -zxvf libxml2-2.7.6.tar.gz cd libxml2-2.7.6 sudo ./configure --prefix=/root/custom/software sudo make sudo make install After installing the above dependencies, you will need to restart your apache server by executing sudo service apache2 restart

Next, you will be ready to install the PECL extension for Solr by cloning the following repository for Solr 4.x. (Please Note: Current;y, the official php-pecl-solr is not compatible with Solr 4.x. The following repository provides a small fix to make it compatible with Solr 4.x and will go to the official release.)

git clone https://github.com/lukaszkujawa/php-pecl-solr.git
cd php-pecl-solr/
phpize
- This a shell script used to prepare the build environment for a php extension to be compiled. If you don't have phpize, you can install it by executing sudo apt-get install php5-dev

If the libxml2 and libcurl libraries were compiled from source, then you will have to pass the libcurl prefix to the configure script for CURL and LIBXML respectively as shown below:

sudo ./configure --enable-solr --with-curl=/root/custom/software --with-libxml-dir=/root/custom/software
If you already have the latest versions of the libraries then executing sudo ./configure is sufficient.
sudo make
sudo make install

The above procedure will compile and install it in the extension_dir directory in the php.ini file. To enable, the installed extension, you could follow any of the following two steps:

1. Navigate to the directory etc/php5/conf.d and create a new solr.ini file with the following line:

extension=solr.so

OR

2. Open your php.ini file and include the following line:

extension=solr.so

You may follow any of the above two steps. You will need to restart your apache server after that by executing sudo service apache2 restart

You can now view the solr extension by executing echo phpinfo(); in browser or php -m in Terminal (Ctrl+Alt+T)

After installing the php-pecl-solr extension, users will have to download Apache Solr, unzip it and keep it in an external directory of Moodle.

Users will have to replace solconfig.xml and schema.xml inside the downloaded directory /example/solr/collection1/conf with the ones that Global Search will provide. Once, the files have been copied and replaced, users will have to start the java jetty server start.jar located in /example/ directory by executing java -jar start.jar.

Documentation

Global search (GSoC2013)

Contents

Introduction

Milestones

Installation

See also