= Project: Full-Text Search =

Name : '''Vishrut Mehta'''[[BR]]
Mentor: '''Pat Tressel'''[[BR]]

=== Proposal ===

The proposal for the project is here:[[BR]]
http://www.google-melange.com/gsoc/proposal/review/google/gsoc2013/vishrutmehta/6001

=== BluePrints ===

This project draws ideas from the Blueprints below:[[BR]]
* BluePrint/TextSearch

=== Meetings And Discussions ===

'''Weekly Meeting''' : '''Tuesday and Saturday 04:30 UTC'''
[[BR]]

'''Venue''' : '''IRC''' [[BR]]
Nick - vishrut009
[[BR]]

'''Google Group Discussions''' : 
  * https://groups.google.com/forum/#!topic/sahana-eden/E0S7Hl_hjWo [[BR]]
  * https://groups.google.com/forum/#!topic/sahana-eden/9XwK4955cmg
[[BR]]

=== Description of Work Done ===

* Pylucene
 * Installation details are here: http://eden.sahanafoundation.org/wiki/BluePrint/TextSearch#Pylucene
* Apache Solr
 * The installation details are here: http://eden.sahanafoundation.org/wiki/BluePrint/TextSearch#ApacheSolr
 
* Sunburnt
 * The script Attached below installs the dependencies and also configures and installs Apache Solr and Sunburnt[[BR]]

* Solr Configuration and Schema changes
 * I have attached an installation script for installing all the dependencies and the solr configuration.
 * You can also install manually. 
 * These are the following dependencies you would need to install:
  * Antiword
  * Pdfminer
  * Pyth
  * Httplib2
  * libxml2, lxml> 3.0
 * After installing all these dependencies, we would need to changed the solr config file, solr-4.3.x/example/solr/collection1/conf/solrconfig.xml
  * Change the directory path, where you want to store all the indexes. This can be stored anywhere, but better to keep in the eden directory. For example, as mentioned in installation script:
{{{
<dataDir>/home/<user>/web2py/applications/eden/indices</dataDir>
}}}
 * You can also change this path according to you suitability, like if solr is on another machine, then the directory path would be different.
 * Now, we will discuss the schema changes in file solr-4.3.x/example/solr/collection1/conf/schema.xml - 
  * Add the following in the <fields>..</fields> tag:
{{{
<fields>
.
.

<field name="tablename" type="text_general" indexed="true" stored="true"/>
<field name="filetype" type="text_general" indexed="true" stored="true"/>
<field name="filename" type="text_general" indexed="true" stored="true"/>

.
.
</fields>
}}}
  * After adding this, after the <fields>..</fields> tag, add the following code for <copyfield>
{{{

<copyField source="filetype" dest="text"/>
<copyField source="tablename" dest="text"/>
<copyField source="filename" dest="text"/>

}}}




* Enabling text search:
-> Uncomment the following line in ''models/000_config.py''
{{{
# Uncomment this and set the solr url to connect to solr server for Full-Text Search
settings.base.solr_url = "http://127.0.0.1:8983/solr/"
}}}
Specify the appropriate IP, like here it is 127.0.0.1[[BR]]
If you are running on different machine, then specify that IP accordingly.


* Asynchronously Indexing and Deleting Documents:
 * The code for asynchronously indexing documents is in ''models/tasks.py'' 
 * '''Insertion''': The code will first insert the document into the database. Then in callback ''onaccept'' it will index those documents calling the document_create_index() function from models/tasks.py . The following code should be added for enabling Full Text search for documents in any modules. The example is there, you can see modules/s3db/doc.py in document_onaccept() hook.
 * '''Deletion''': The code will first delete the record from the database table, then will select that file and will delete it from Solr also, by deleting its index which is stored in solr server. You can look for the code in modules/s3db/doc.py in document_ondelete() hook.
 * In model()
{{{


        if settings.get_base_solr_url():
            onaccept = self.document_onaccept # where document_onaccept is the onaccept hook for indexing
            ondelete = self.document_ondelete # where document_onaccept is the onaccept hook for deleting
        else:
            onaccept = None
            ondelete = None

        configure(tablename,
                  onaccept=onaccept,
                  ondelete=ondelete,
        .....



}}}
 * In onaccept()
{{{
    @staticmethod
    def document_onaccept(form):

        vars = form.vars
        doc = vars.file # where file is the name of the upload field

        table = current.db.doc_document # doc_document is the tablename
        try:
            name = table.file.retrieve(doc)[0]
        except TypeError:
            name = doc

        document = json.dumps(dict(filename=doc,
                                  name=name,
                                  id=vars.id,
                                  tablename="doc_document", # where "doc_document" is the name of the database table
                                  ))

        current.s3task.async("document_create_index",
                             args = [document])

        return



}}}
 * in ondelete():
{{{
    @staticmethod
    def document_ondelete(row):

        db = current.db
        table = db.doc_document # doc_document is the tablename

        record = db(table.id == row.id).select(table.file, # where file is the name of the upload field
                                               limitby=(0, 1)).first()

        document = json.dumps(dict(filename=record.file, # where file is the name of the upload field
                                  id=row.id,
                                 ))

        current.s3task.async("document_delete_index",
                             args = [document])

        return

}}}

=== Full Text Functionality ===

* The full text search functionality is integrated in modules/s3/s3resource.py, the fulltext() does the work.
* The flow is: First the TEXT query goes to transform() function, which would split the query recursively and then transform the query.
* After transforming, the query with TEXT operator will go to fulltext() function and would search for the keywords in the indexed documents.
* It will retrieve document ids and then covert into a BELONGS S3ResourceQuery.
* The code sample for the fulltext() is in ''models/s3/s3resource.py''

=== Unit Test ===

* Unit Tests are important part of any code function to check ifs its working according to our expectation.
* For Full Text Search also, I have implemented it in ''modules/unit_tests/s3/s3resource.py'' - Class DocumentFullTextSearchTests
* For checking the code in different situations, so all errors are removed, there are different tests implemented for it. The cases are:
 * When Solr is available (Solr server is running normally)
 * When Solr is unavailable (Solr server is not running, but enabled)
 * Checking the output of query() function
 * Checking the output of call() function

[[BR]][[BR]]




||= SMART Goal =||= Measure =||= Status =||
|| Explore Pylucene || Installed and configured on demo server || Completed ||
|| Scripts for indexing and search in pylucene || Scripts working on the demo server || Completed ||
|| Explore Apache Solr and Sunburnt || Installed both on demo and local server || Completed ||
|| Scripts for indexing and search for sunburnt || Working scripts for sunburnt ready || Completed ||
|| Asynchronously Indexing and Deleting Document || Implemented & Integrated in Sahana Eden || Completed ||
|| Install Script foe Installing and Configuring Solr and sunburnt || Below is the link of the script || Completed || 
|| Designing the Full-Text search functionality implementation || Discussed with Dominic and Fran || Completed ||
|| Implementation of fulltext() function in s3resource.py || Successfully implemented with Error handling || Completed ||
|| Implemented a transform() function to transform a TEXT query to __belong query || Successfully implemented with Error handling || Completed ||
|| Unit tests for all cases(solr un/available, query(), __call__() ) || Implemented the unit tests for s3resource || Almost Done ||
|| Generic Indexing onaccept() hook, can be integrated in any module || Implemented and tested on doc_document || Completed ||