search_simpledb\engine Class Reference

Simple moodle database engine. More...

Inheritance diagram for search_simpledb\engine:

Public Member Functions
	add_document ($document, $fileindexing=false)
	Adds a document to the search engine.
	add_document_batch (array $documents, bool $fileindexing=false)
	Adds multiple documents to the search engine.
	add_documents ($iterator, $searcharea, $options)
	Loop through given iterator of search documents and and have the search engine back end add them to the index.
	area_index_complete ($searcharea, $numdocs=0, $fullindex=false)
	Do any area cleanup needed, and do anything to confirm contents.
	area_index_starting ($searcharea, $fullindex=false)
	Do anything that may need to be done before an area is indexed.
	check_latest_schema ()
	Checks that the schema is the latest version.
	clear_query_error ()
	Clears the current query error value.
	delete ($areaid=null)
	Delete all area's documents.
	delete_by_id ($id)
	Deletes the specified document.
	delete_index_for_context (int $oldcontextid)
	Simpledb supports deleting the index for a context.
	delete_index_for_course (int $oldcourseid)
	Simpledb supports deleting the index for a course.
	execute_query ($filters, $usercontexts, $limit=0)
	Prepares a SQL query, applies filters and executes it returning its results.
	file_indexing_enabled ()
	Return true if file indexing is supported and enabled.
	get_batch_max_content ()
	Gets the maximum size of document content to be included in a shared batch (if the document is bigger then it will be sent on its own; batching does not provide a performance improvement for big documents anyway).
int	get_batch_max_documents ()
	Gets the maximum number of documents to send together in batch mode.
	get_document_classname ()
	Gets the document class used by this search engine.
	get_plugin_name ()
	Returns the plugin name.
	get_query_error ()
	Returns any error reported by the search engine when executing the provided query.
	get_query_total_count ()
	Returns the total results.
	get_supported_orders (\context $context)
	Obtain a list of results orders (and names for them) that are supported by this search engine in the given context.
	get_user ($userid)
	Returns user data checking the internal static cache.
	has_alternate_configuration ()
	Checks if the search engine has an alternate configuration.
	index_complete ($numdocs=0, $fullindex=false)
	Run any post indexing operations.
	index_starting ($fullindex=false)
	Run any pre-indexing operations.
	is_installed ()
	It is always installed.
	is_server_ready ()
	Checks that the required table was installed.
	optimize ()
	Optimizes the search engine.
	record_applied_schema_version ($version)
	Usually called by the engine; marks that the schema has been updated.
	skip_schema_check ($skip=true)
	Tells the search engine to skip any time-consuming checks that it might do as part of the is_server_ready function, and only carry out a basic check that it can contact the server.
	supports_add_document_batch ()
	Checks if the search engine supports adding documents in a batch.
	supports_group_filtering ()
	Checks if this search engine supports groups.
	supports_users ()
	Checks if the search engine supports searching by user.

Static Public Member Functions
static	clear_users_cache ()
	Clears the users cache.

Protected Member Functions
	get_course ($courseid)
	Returns a course instance checking internal caching.
	get_search_area ($areaid)
	Returns a search instance of the specified area checking internal caching.
	get_simple_query ($q)
	Returns the default query for db engines.
	should_skip_schema_check ()
	For use by subclasses.
	to_document (\core_search\base $searcharea, $docdata)
	Returns a document instance prepared to be rendered.
	update_schema ($oldversion, $newversion)
	Requests the search engine to upgrade the schema.

Protected Attributes
array	$cachedareas = array()
	Internal cache.
array	$cachedcourses = array()
	Internal cache.
stdClass	$config = null
	The search engine configuration.
string	$pluginname = null
	Frankenstyle plugin name.
string	$queryerror = null
	Last executed query error, if there was any.
bool	$skipschemacheck = false
	If true, should skip schema validity check when checking the search engine is ready.
null int	$totalresults = null
	Total number of available results.

Static Protected Attributes
static stdClass[]	$cachedusers = array()
	User data required to show their fullnames.

Detailed Description

Simple moodle database engine.

Copyright

2016 David Monllao

License

http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

Member Function Documentation

add_document()

search_simpledb\engine::add_document	(		$document,
			$fileindexing = false )

Adds a document to the search engine.

This does not commit to the search engine.

Parameters

core_search\document	$document
bool	$fileindexing	True if file indexing is to be used

Return values

bool	False if the file was skipped or failed, true on success

Reimplemented from core_search\engine.

add_document_batch()

core_search\engine::add_document_batch ( array $documents, bool $fileindexing = false )

inherited

Adds multiple documents to the search engine.

It should return the number successfully processed, and the number of batches they were processed in (for example if you add 100 documents and there is an error processing one of those documents, and it took 4 batches, it would return [99, 1, 4]).

If the engine implements this, it should return true to {

See also

supports_add_document_batch}.

The system will only call this function with up to {

See also

get_batch_max_documents} documents, and each document in the batch will have content no larger than specified by {

get_batch_max_content}.

Parameters

document[]	$documents	Documents to add
bool	$fileindexing	True if file indexing is to be used

Return values

int[]

Array of three elements, successfully processed, failed processed, batch count

Reimplemented in search_solr\engine.

add_documents()

core_search\engine::add_documents ( $iterator, $searcharea, $options )

inherited

Loop through given iterator of search documents and and have the search engine back end add them to the index.

Parameters

iterator	$iterator	the iterator of documents to index
base	$searcharea	the area for the documents to index
array	$options	document indexing options

Return values

array

Processed document counts

area_index_complete()

core_search\engine::area_index_complete ( $searcharea, $numdocs = 0, $fullindex = false )

inherited

Do any area cleanup needed, and do anything to confirm contents.

Return false to prevent the search area completed time and stats from being updated.

Parameters

core_search\base	$searcharea	The search area that was complete
int	$numdocs	The number of documents that were added to the index
bool	$fullindex	True if a full index is being performed

Return values

bool	True means that data is considered indexed

Reimplemented in search_solr\engine.

area_index_starting()

core_search\engine::area_index_starting ( $searcharea, $fullindex = false )

inherited

Do anything that may need to be done before an area is indexed.

Parameters

core_search\base	$searcharea	The search area that was complete
bool	$fullindex	True if a full index is being performed

Return values

void

check_latest_schema()

core_search\engine::check_latest_schema ( )

inherited

Checks that the schema is the latest version.

If the version stored in config does not match the current, this function will attempt to upgrade the schema.

Return values

bool|string

True if schema is OK, a string if user needs to take action

clear_query_error()

core_search\engine::clear_query_error ( )

inherited

Clears the current query error value.

Return values

void

clear_users_cache()

static core_search\engine::clear_users_cache ( )

staticinherited

Clears the users cache.

Return values

null

delete()

search_simpledb\engine::delete

(

$areaid = null

)

Delete all area's documents.

Parameters

string

$areaid

Return values

void

Reimplemented from core_search\engine.

delete_by_id()

search_simpledb\engine::delete_by_id

(

$id

)

Deletes the specified document.

Parameters

string

$id

The document id to delete

Return values

void

delete_index_for_context()

search_simpledb\engine::delete_index_for_context

(

int

$oldcontextid

)

Simpledb supports deleting the index for a context.

Parameters

int

$oldcontextid

Context that has been deleted

Return values

bool	True to indicate that any data was actually deleted

Exceptions

core_search\engine_exception

Reimplemented from core_search\engine.

delete_index_for_course()

search_simpledb\engine::delete_index_for_course

(

int

$oldcourseid

)

Simpledb supports deleting the index for a course.

Parameters

int

$oldcourseid

Return values

bool	True to indicate that any data was actually deleted

Exceptions

core_search\engine_exception

Reimplemented from core_search\engine.

execute_query()

search_simpledb\engine::execute_query	(		$filters,
			$usercontexts,
			$limit = 0 )

Prepares a SQL query, applies filters and executes it returning its results.

Exceptions

core_search\engine_exception

Parameters

stdClass	$filters	Containing query and filters.
array	$usercontexts	Contexts where the user has access. True if the user can access all contexts.
int	$limit	The maximum number of results to return.

Return values

core_search\document[]

Results or false if no results

Reimplemented from core_search\engine.

file_indexing_enabled()

core_search\engine::file_indexing_enabled ( )

inherited

Return true if file indexing is supported and enabled.

False otherwise.

Return values

bool

Reimplemented in search_solr\engine.

get_batch_max_content()

core_search\engine::get_batch_max_content ( )

inherited

Gets the maximum size of document content to be included in a shared batch (if the document is bigger then it will be sent on its own; batching does not provide a performance improvement for big documents anyway).

Only relevant if the engine returns true to {

See also

supports_add_document_batch}.

Can be overridden by search engine if required.

Return values

int	Max size in bytes, default 1MB

get_batch_max_documents()

int core_search\engine::get_batch_max_documents ( )

inherited

Gets the maximum number of documents to send together in batch mode.

Only relevant if the engine returns true to {

See also

supports_add_document_batch}.

Can be overridden by search engine if required.

Number of documents to send together in batch mode, default 100.

get_course()

core_search\engine::get_course ( $courseid )

protectedinherited

Returns a course instance checking internal caching.

Parameters

int

$courseid

Return values

stdClass

get_document_classname()

core_search\engine::get_document_classname ( )

inherited

Gets the document class used by this search engine.

Search engines can overwrite core_search\document with search_ENGINENAME\document class.

Looks for a document class in the current search engine namespace, falling back to core_search\document.

Publicly available because search areas do not have access to the engine details, core_search\document_factory accesses this function.

Return values

string

get_plugin_name()

core_search\engine::get_plugin_name ( )

inherited

Returns the plugin name.

Return values

string

Frankenstyle plugin name.

get_query_error()

core_search\engine::get_query_error ( )

inherited

Returns any error reported by the search engine when executing the provided query.

It should be called from static\execute_query when an exception is triggered.

Return values

string

get_query_total_count()

search_simpledb\engine::get_query_total_count

(

)

Returns the total results.

Including skipped results.

Return values

int

Reimplemented from core_search\engine.

get_search_area()

core_search\engine::get_search_area ( $areaid )

protectedinherited

Returns a search instance of the specified area checking internal caching.

Parameters

string

$areaid

Area id

Return values

core_search\base

get_simple_query()

search_simpledb\engine::get_simple_query ( $q )

protected

Returns the default query for db engines.

Parameters

string

$q

The query string

Return values

array

SQL string and params list

get_supported_orders()

core_search\engine::get_supported_orders ( \context $context )

inherited

Obtain a list of results orders (and names for them) that are supported by this search engine in the given context.

By default, engines sort by relevance only.

Parameters

context

$context

Context that the user requested search from

Return values

array

Array from order name => display text

Reimplemented in search_solr\engine.

get_user()

core_search\engine::get_user ( $userid )

inherited

Returns user data checking the internal static cache.

Including here the minimum required user information as this may grow big.

Parameters

int

$userid

Return values

stdClass

has_alternate_configuration()

core_search\engine::has_alternate_configuration ( )

inherited

Checks if the search engine has an alternate configuration.

This is used where the same search engine class supports two different configurations, which are both shown on the settings screen. The alternate configuration is selected by passing 'true' parameter to the constructor.

The feature is used when a different connection is in use for indexing vs. querying the search engine.

This function should only return true if the engine supports an alternate configuration and the user has filled in the settings. (We do not need to test they are valid, that will happen as normal.)

Return values

bool	True if an alternate configuration is defined

Reimplemented in search_solr\engine.

index_complete()

core_search\engine::index_complete ( $numdocs = 0, $fullindex = false )

inherited

Run any post indexing operations.

Should be overwritten if the search engine needs to do any post index cleanup.

Parameters

int	$numdocs	The number of documents that were added to the index
bool	$fullindex	True if a full index was performed

Return values

void

index_starting()

core_search\engine::index_starting ( $fullindex = false )

inherited

Run any pre-indexing operations.

Should be overwritten if the search engine needs to do any pre index preparation.

Parameters

bool

$fullindex

True if a full index will be performed

Return values

void

is_installed()

search_simpledb\engine::is_installed

(

)

It is always installed.

Return values

true

Reimplemented from core_search\engine.

is_server_ready()

search_simpledb\engine::is_server_ready

(

)

Checks that the required table was installed.

Return values

true|string

Returns true if all good or an error string.

Reimplemented from core_search\engine.

optimize()

core_search\engine::optimize ( )

inherited

Optimizes the search engine.

Should be overwritten if the search engine can optimize its contents.

Return values

void

record_applied_schema_version()

core_search\engine::record_applied_schema_version ( $version )

inherited

Usually called by the engine; marks that the schema has been updated.

Parameters

int

$version

Records the schema version now applied

should_skip_schema_check()

core_search\engine::should_skip_schema_check ( )

protectedinherited

For use by subclasses.

The engine can call this inside is_server_ready to check whether it should skip time-consuming schema checks.

Since

Moodle 3.5

Return values

bool	True if schema checks should be skipped

skip_schema_check()

core_search\engine::skip_schema_check ( $skip = true )

inherited

Tells the search engine to skip any time-consuming checks that it might do as part of the is_server_ready function, and only carry out a basic check that it can contact the server.

This setting is not remembered and applies only to the current request.

Since

Moodle 3.5

Parameters

bool

$skip

True to skip the checks, false to start checking again

supports_add_document_batch()

core_search\engine::supports_add_document_batch ( )

inherited

Checks if the search engine supports adding documents in a batch.

If it returns true to this function, the search engine must implement the add_document_batch function.

Return values

bool	True if the search engine supports adding documents in a batch

Reimplemented in search_solr\engine.

supports_group_filtering()

core_search\engine::supports_group_filtering ( )

inherited

Checks if this search engine supports groups.

Note that returning true to this function causes the parameters to execute_query to be passed differently!

In order to implement groups and return true to this function, the search engine should:

1. Handle the fields ->separategroupscontexts and ->usergroups in the $accessinfo parameter to execute_query (ideally, using these to automatically restrict search results).
2. Support the optional groupids parameter in the $filter parameter for execute_query to restrict results to only those where the stored groupid matches the given value.

Return values

bool	True if this engine supports searching by group id field

Reimplemented in search_solr\engine.

supports_users()

core_search\engine::supports_users ( )

inherited

Checks if the search engine supports searching by user.

If it returns true to this function, the search engine should support the 'userids' option in the $filters value passed to execute_query(), returning only items where the userid in the search document matches one of those user ids.

Return values

bool	True if the search engine supports searching by user

Reimplemented in search_solr\engine.

to_document()

core_search\engine::to_document ( \core_search\base $searcharea, $docdata )

protectedinherited

Returns a document instance prepared to be rendered.

Parameters

core_search\base	$searcharea
array	$docdata

Return values

core_search\document

update_schema()

core_search\engine::update_schema ( $oldversion, $newversion )

protectedinherited

Requests the search engine to upgrade the schema.

The engine should update the schema if possible/necessary, and should ensure that record_applied_schema_version is called as a result.

If it is not possible to upgrade the schema at the moment, it can do nothing and return; the function will be called again next time search is initialised.

The default implementation just returns, with a DEBUG_DEVELOPER warning.

Parameters

int	$oldversion	Old schema version
int	$newversion	New schema version

Return values

bool|string

True if schema is updated successfully, a string if it needs updating manually

Reimplemented in search_solr\engine.

Member Data Documentation

$cachedusers

stdClass [] core_search\engine::$cachedusers = array()

staticprotectedinherited

User data required to show their fullnames.

Indexed by userid.

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The documentation for this class was generated from the following file:

• search/engine/simpledb/classes/engine.php