opigno_scorm.manifest.inc in Opigno 7
Manifest file extraction logic.
Contains functions for parsing the manifest XML, treating the data recursively and preparing the data for storage. Only data that is relevant to a SCORM player is stored. For example, resource information is not stored.
File
modules/scorm/includes/opigno_scorm.manifest.incView source
<?php
/**
* @file
* Manifest file extraction logic.
*
* Contains functions for parsing the manifest XML, treating the data recursively and
* preparing the data for storage. Only data that is relevant to a SCORM player is stored.
* For example, resource information is not stored.
*/
// XML tag names
define('OPIGNO_SCORM_MANIFEST_METADATA', 'METADATA');
define('OPIGNO_SCORM_MANIFEST_ORGANIZATIONS', 'ORGANIZATIONS');
define('OPIGNO_SCORM_MANIFEST_ORGANIZATION', 'ORGANIZATION');
define('OPIGNO_SCORM_MANIFEST_RESOURCES', 'RESOURCES');
define('OPIGNO_SCORM_MANIFEST_RESOURCE', 'RESOURCE');
define('OPIGNO_SCORM_MANIFEST_TITLE', 'TITLE');
define('OPIGNO_SCORM_MANIFEST_ITEM', 'ITEM');
define('OPIGNO_SCORM_MANIFEST_SEQUENCING', 'IMSSS:SEQUENCING');
define('OPIGNO_SCORM_MANIFEST_CTRL_MODE', 'IMSSS:CONTROLMODE');
define('OPIGNO_SCORM_MANIFEST_OBJECTIVES', 'IMSSS:OBJECTIVES');
define('OPIGNO_SCORM_MANIFEST_OBJECTIVE', 'IMSSS:OBJECTIVE');
define('OPIGNO_SCORM_MANIFEST_PRIMARY_OBJECTIVE', 'IMSSS:PRIMARYOBJECTIVE');
define('OPIGNO_SCORM_MANIFEST_MIN_NORMALIZED_MEASURE', 'IMSSS:MINNORMALIZEDMEASURE');
define('OPIGNO_SCORM_MANIFEST_MAX_NORMALIZED_MEASURE', 'IMSSS:MAXNORMALIZEDMEASURE');
// XML attributes
define('OPIGNO_SCORM_MANIFEST_DEFAULT_ATTR', 'DEFAULT');
define('OPIGNO_SCORM_MANIFEST_ID_ATTR', 'IDENTIFIER');
define('OPIGNO_SCORM_MANIFEST_REFID_ATTR', 'IDENTIFIERREF');
define('OPIGNO_SCORM_MANIFEST_LAUNCH_ATTR', 'LAUNCH');
define('OPIGNO_SCORM_MANIFEST_PARAM_ATTR', 'PARAMETERS');
define('OPIGNO_SCORM_MANIFEST_TYPE_ATTR', 'TYPE');
define('OPIGNO_SCORM_MANIFEST_SCORM_TYPE_ATTR', 'ADLCP:SCORMTYPE');
define('OPIGNO_SCORM_MANIFEST_HREF_ATTR', 'HREF');
define('OPIGNO_SCORM_MANIFEST_MANIFEST_ATTR', 'IDENTIFIER');
define('OPIGNO_SCORM_MANIFEST_CHOICE_ATTR', 'CHOICE');
define('OPIGNO_SCORM_MANIFEST_FLOW_ATTR', 'FLOW');
define('OPIGNO_SCORM_MANIFEST_CHOICE_EXIT_ATTR', 'CHOICEEXIT');
define('OPIGNO_SCORM_MANIFEST_OBJECTIVE_ID_ATTR', 'OBJECTIVEID');
define('OPIGNO_SCORM_MANIFEST_OBJECTIVE_SATISFIED_BY_MEASURE_ATTR', 'SATISFIEDBYMEASURE');
/**
* Extract the SCORM package from the file.
*
* Given a file ID (which should be a valid SCORM ZIP file), this function extracts
* the ZIP to OPIGNO_SCORM_DIRECTORY, finds the manifest file and parses it.
* Once parsed, it stores the manifest data.
*
* Returns the id of the extracted SCORM package, or FALSE if an error occurs.
*
* @param int $fid
* The file ID that we'll extract.
*
* @return int|false
*/
function opigno_scorm_extract($fid) {
$file = file_load($fid);
$path = drupal_realpath($file->uri);
$zip = new ZipArchive();
$result = $zip
->open($path);
if ($result === TRUE) {
$extract_dir = OPIGNO_SCORM_DIRECTORY . '/scorm_' . $fid;
$zip
->extractTo($extract_dir);
$zip
->close();
// This is a standard: the manifest file will always be here.
$manifest_file = $extract_dir . '/imsmanifest.xml';
if (file_exists($manifest_file)) {
// Prepare the Scorm DB entry.
$scorm = (object) array(
'fid' => $fid,
'extracted_dir' => $extract_dir,
'manifest_file' => $manifest_file,
'manifest_id' => '',
'metadata' => '',
);
// Parse the manifest file and extract the data.
$manifest_data = opigno_scorm_extract_manifest_data($manifest_file);
// Get the manifest ID, if it's given.
if (!empty($manifest_data['manifest_id'])) {
$scorm->manifest_id = $manifest_data['manifest_id'];
}
// If the file contains (global) metadata, serialize it.
if (!empty($manifest_data['metadata'])) {
$scorm->metadata = serialize($manifest_data['metadata']);
}
// Try saving the SCORM to the DB.
if (opigno_scorm_scorm_save($scorm)) {
// Store each SCO.
if (!empty($manifest_data['scos']['items'])) {
foreach ($manifest_data['scos']['items'] as $i => $sco_item) {
$sco = (object) array(
'scorm_id' => $scorm->id,
'organization' => $sco_item['organization'],
'identifier' => $sco_item['identifier'],
'parent_identifier' => $sco_item['parent_identifier'],
'launch' => $sco_item['launch'],
'type' => $sco_item['type'],
'scorm_type' => $sco_item['scorm_type'],
'title' => $sco_item['title'],
'weight' => empty($sco_item['weight']) ? $sco_item['weight'] : 0,
'attributes' => $sco_item['attributes'],
);
if (opigno_scorm_sco_save($sco)) {
// @todo Store SCO attributes.
}
else {
watchdog('opigno_scorm', "An error occured when saving an SCO.", array(), WATCHDOG_ERROR);
}
}
}
return TRUE;
}
else {
watchdog('opigno_scorm', "An error occured when saving the SCORM package data.", array(), WATCHDOG_ERROR);
}
}
}
else {
$error = 'none';
switch ($result) {
case ZipArchive::ER_EXISTS:
$error = 'ER_EXISTS';
break;
case ZipArchive::ER_INCONS:
$error = 'ER_INCONS';
break;
case ZipArchive::ER_INVAL:
$error = 'ER_INVAL';
break;
case ZipArchive::ER_NOENT:
$error = 'ER_NOENT';
break;
case ZipArchive::ER_NOZIP:
$error = 'ER_NOZIP';
break;
case ZipArchive::ER_OPEN:
$error = 'ER_OPEN';
break;
case ZipArchive::ER_READ:
$error = 'ER_READ';
break;
case ZipArchive::ER_SEEK:
$error = 'ER_SEEK';
break;
}
watchdog('opigno_scorm', "An error occured when unziping the SCORM package data. Error: !error", array(
'!error' => $error,
), WATCHDOG_ERROR);
}
return FALSE;
}
/**
* Extract the manifest data.
*
* Parse the manifest XML with XML2Array (located in includes/XML2Array.php)
* and extract data that is relevant to us.
*
* @param string $manifest_file
*
* @return array
*/
function opigno_scorm_extract_manifest_data($manifest_file) {
$data = array();
// Get the XML as a string.
$manifest_string = file_get_contents($manifest_file);
// Parse it as an array.
$parser = new XML2Array();
$manifest = $parser
->parse($manifest_string);
// The parser returns an array of arrays - skip the first element.
$manifest = array_shift($manifest);
// Get the manifest ID, if any.
if (!empty($manifest['attrs'][OPIGNO_SCORM_MANIFEST_MANIFEST_ATTR])) {
$data['manifest_id'] = $manifest['attrs'][OPIGNO_SCORM_MANIFEST_MANIFEST_ATTR];
}
else {
$data['manifest_id'] = '';
}
// Extract the global metadata information.
$data['metadata'] = opigno_scorm_extract_manifest_metadata($manifest);
// Extract the SCOs (course items). Gets the default SCO and a list of all SCOs.
$data['scos'] = opigno_scorm_extract_manifest_scos($manifest);
// Extract the resources, so we can combine the SCOs and resources.
$data['resources'] = opigno_scorm_extract_manifest_resources($manifest);
// Combine the resources and SCOs.
$data['scos']['items'] = opigno_scorm_combine_manifest_sco_and_resources($data['scos']['items'], $data['resources']);
return $data;
}
/**
* Extract the manifest metadata.
*
* Find the metadata of this manifest file and return it.
* We only treat global metadata - we don't parse metadata on SCOs or
* resources.
*
* @param array $manifest
*
* @return array
*/
function opigno_scorm_extract_manifest_metadata($manifest) {
foreach ($manifest['children'] as $child) {
if ($child['name'] == OPIGNO_SCORM_MANIFEST_METADATA) {
$meta = array();
foreach ($child['children'] as $metadata) {
$meta[strtolower($metadata['name'])] = $metadata['tagData'];
}
return $meta;
}
}
return array();
}
/**
* Extract the manifest SCO items.
*
* @see _opigno_scorm_extract_manifest_scos_items().
*
* @param array $manifest
*
* @return array
* 'items' => array of SCOs
* 'default' => default SCO identifier
*/
function opigno_scorm_extract_manifest_scos($manifest) {
$items = array(
'items' => array(),
);
foreach ($manifest['children'] as $child) {
if ($child['name'] == OPIGNO_SCORM_MANIFEST_ORGANIZATIONS) {
if (!empty($child['attrs'][OPIGNO_SCORM_MANIFEST_DEFAULT_ATTR])) {
$items['default'] = $child['attrs'][OPIGNO_SCORM_MANIFEST_DEFAULT_ATTR];
}
else {
$items['default'] = '';
}
$items['items'] = array_merge(_opigno_scorm_extract_manifest_scos_items($child['children']), $items['items']);
}
}
return $items;
}
/**
* Helper function to recursively extract the manifest SCO items.
*
* The data is extracted as a flat array - it contains to hierarchy. Because of this,
* the items are not extracted in logical order. However, each "level" is given a weight
* which allows us to know how to organize them.
*
* @param array $manifest
* @param string|int $parent_identifier = 0
* @param string $organization = ''
*
* @return array
*/
function _opigno_scorm_extract_manifest_scos_items($manifest, $parent_identifier = 0, $organization = '') {
$items = array();
$weight = 0;
foreach ($manifest as $item) {
if (in_array($item['name'], array(
OPIGNO_SCORM_MANIFEST_ORGANIZATION,
OPIGNO_SCORM_MANIFEST_ITEM,
)) && !empty($item['children'])) {
$attributes = array();
if (!empty($item['attrs'][OPIGNO_SCORM_MANIFEST_ID_ATTR])) {
$identifier = $item['attrs'][OPIGNO_SCORM_MANIFEST_ID_ATTR];
}
else {
$identifier = uniqid();
}
if (!empty($item['attrs'][OPIGNO_SCORM_MANIFEST_LAUNCH_ATTR])) {
$launch = $item['attrs'][OPIGNO_SCORM_MANIFEST_LAUNCH_ATTR];
}
else {
$launch = '';
}
if (!empty($item['attrs'][OPIGNO_SCORM_MANIFEST_REFID_ATTR])) {
$resource_identifier = $item['attrs'][OPIGNO_SCORM_MANIFEST_REFID_ATTR];
}
else {
$resource_identifier = '';
}
if (!empty($item['attrs'][OPIGNO_SCORM_MANIFEST_PARAM_ATTR])) {
$attributes['parameters'] = $item['attrs'][OPIGNO_SCORM_MANIFEST_PARAM_ATTR];
}
if (!empty($item['attrs'][OPIGNO_SCORM_MANIFEST_TYPE_ATTR])) {
$type = $item['attrs'][OPIGNO_SCORM_MANIFEST_TYPE_ATTR];
}
else {
$type = '';
}
if (!empty($item['attrs'][OPIGNO_SCORM_MANIFEST_SCORM_TYPE_ATTR])) {
$scorm_type = $item['attrs'][OPIGNO_SCORM_MANIFEST_SCORM_TYPE_ATTR];
}
else {
$scorm_type = '';
}
// Find the title, which is also a child node.
foreach ($item['children'] as $child) {
if ($child['name'] == OPIGNO_SCORM_MANIFEST_TITLE) {
$title = $child['tagData'];
break;
}
}
// Find any sequencing control modes, which are also child nodes.
$control_modes = array();
foreach ($item['children'] as $child) {
if ($child['name'] == OPIGNO_SCORM_MANIFEST_SEQUENCING) {
$control_modes = opigno_scorm_extract_item_sequencing_control_modes($child);
$attributes['objectives'] = opigno_scorm_extract_item_sequencing_objectives($child);
}
}
// Failsafe - we cannot have elements without a title.
if (empty($title)) {
$title = 'NO TITLE';
}
$items[] = array(
'manifest' => '',
// @deprecated
'organization' => $organization,
'title' => $title,
'identifier' => $identifier,
'parent_identifier' => $parent_identifier,
'launch' => $launch,
'resource_identifier' => $resource_identifier,
'type' => $type,
'scorm_type' => $scorm_type,
'weight' => $weight,
'attributes' => $control_modes + $attributes,
);
// The first item is not an "item", but an "organization" node. This is the organization
// for the remainder of the tree. Get it, and pass it along, so we know to which organization
// the SCOs belong.
if (empty($organization) && $item['name'] == OPIGNO_SCORM_MANIFEST_ORGANIZATION) {
$organization = $identifier;
}
// Recursively get child items, and merge them to get a flat list.
$items = array_merge(_opigno_scorm_extract_manifest_scos_items($item['children'], $identifier, $organization), $items);
}
$weight++;
}
return $items;
}
/**
* Extract the manifest SCO item sequencing objective.
*
* This extracts sequencing objectives from an item. Objectives allow the system
* to know how to "grade" the SCORM object.
*
* @param array $item_manifest
*
* @return array
*/
function opigno_scorm_extract_item_sequencing_objectives($item_manifest) {
$objectives = array();
foreach ($item_manifest['children'] as $child) {
if ($child['name'] == OPIGNO_SCORM_MANIFEST_OBJECTIVES) {
foreach ($child['children'] as $child_objective) {
if (!empty($child_objective['attrs'][OPIGNO_SCORM_MANIFEST_OBJECTIVE_ID_ATTR])) {
$id = $child_objective['attrs'][OPIGNO_SCORM_MANIFEST_OBJECTIVE_ID_ATTR];
}
else {
$id = uniqid();
}
if ($child_objective['name'] == OPIGNO_SCORM_MANIFEST_PRIMARY_OBJECTIVE) {
// Note: boolean attributes are stored as a strings. PHP does not know
// how to cast 'false' to FALSE. Use string comparisons to bypass
// this limitation by PHP. See below.
$satisfied_by_measure = FALSE;
if (!empty($child_objective['attrs'][OPIGNO_SCORM_MANIFEST_OBJECTIVE_SATISFIED_BY_MEASURE_ATTR])) {
$satisfied_by_measure = strtolower($child_objective['attrs'][OPIGNO_SCORM_MANIFEST_OBJECTIVE_SATISFIED_BY_MEASURE_ATTR]) === 'true';
}
$objective = array(
'primary' => TRUE,
'secondary' => FALSE,
'id' => $id,
'satisfied_by_measure' => $satisfied_by_measure,
);
foreach ($child_objective['children'] as $primary_obj_child) {
if ($primary_obj_child['name'] == OPIGNO_SCORM_MANIFEST_MIN_NORMALIZED_MEASURE) {
$objective['min_normalized_measure'] = $primary_obj_child['tagData'];
}
elseif ($primary_obj_child['name'] == OPIGNO_SCORM_MANIFEST_MAX_NORMALIZED_MEASURE) {
$objective['max_normalized_measure'] = $primary_obj_child['tagData'];
}
}
$objectives[] = $objective;
}
elseif ($child_objective['name'] == OPIGNO_SCORM_MANIFEST_OBJECTIVE) {
$objectives[] = array(
'primary' => FALSE,
'secondary' => TRUE,
'id' => $id,
);
}
}
}
}
return $objectives;
}
/**
* Extract the manifest SCO item sequencing control modes.
*
* This extracts sequencing control modes from an item. Control modes
* describe how the user can navigate around the course
* (e.g.: display the tree or not, skip SCOs, etc).
*
* @param array $item_manifest
*
* @return array
*/
function opigno_scorm_extract_item_sequencing_control_modes($item_manifest) {
$defaults = array(
'control_mode_choice' => TRUE,
'control_mode_flow' => FALSE,
'control_mode_choice_exit' => TRUE,
'control_mode_forward_only' => FALSE,
);
$control_modes = array();
foreach ($item_manifest['children'] as $child) {
if ($child['name'] == OPIGNO_SCORM_MANIFEST_CTRL_MODE) {
// Note: boolean attributes are stored as a strings. PHP does not know
// how to cast 'false' to FALSE. Use string comparisons to bypass
// this limitation by PHP. See below.
if (!empty($child['attrs'][OPIGNO_SCORM_MANIFEST_CHOICE_ATTR])) {
$control_modes['control_mode_choice'] = strtolower($child['attrs'][OPIGNO_SCORM_MANIFEST_CHOICE_ATTR]) === 'true';
}
if (!empty($child['attrs'][OPIGNO_SCORM_MANIFEST_FLOW_ATTR])) {
$control_modes['control_mode_flow'] = strtolower($child['attrs'][OPIGNO_SCORM_MANIFEST_FLOW_ATTR]) === 'true';
}
if (!empty($child['attrs'][OPIGNO_SCORM_MANIFEST_CHOICE_EXIT_ATTR])) {
$control_modes['control_mode_choice_exit'] = strtolower($child['attrs'][OPIGNO_SCORM_MANIFEST_CHOICE_EXIT_ATTR]) === 'true';
}
}
}
return $control_modes + $defaults;
}
/**
* Extract the manifest SCO resources.
*
* We only extract resource information that is relevant to us. We don't care about
* references files, dependencies, etc. Only about the href attribute, type and
* identifier.
*
* @param array $manifest
*
* @return array
*/
function opigno_scorm_extract_manifest_resources($manifest) {
$items = array();
foreach ($manifest['children'] as $child) {
if ($child['name'] == OPIGNO_SCORM_MANIFEST_RESOURCES) {
foreach ($child['children'] as $resource) {
if ($resource['name'] == OPIGNO_SCORM_MANIFEST_RESOURCE) {
if (!empty($resource['attrs'][OPIGNO_SCORM_MANIFEST_ID_ATTR])) {
$identifier = $resource['attrs'][OPIGNO_SCORM_MANIFEST_ID_ATTR];
}
else {
$identifier = uniqid();
}
if (!empty($resource['attrs'][OPIGNO_SCORM_MANIFEST_HREF_ATTR])) {
$href = $resource['attrs'][OPIGNO_SCORM_MANIFEST_HREF_ATTR];
}
else {
$href = '';
}
if (!empty($resource['attrs'][OPIGNO_SCORM_MANIFEST_TYPE_ATTR])) {
$type = $resource['attrs'][OPIGNO_SCORM_MANIFEST_TYPE_ATTR];
}
else {
$type = '';
}
if (!empty($resource['attrs'][OPIGNO_SCORM_MANIFEST_SCORM_TYPE_ATTR])) {
$scorm_type = $resource['attrs'][OPIGNO_SCORM_MANIFEST_SCORM_TYPE_ATTR];
}
else {
$scorm_type = '';
}
$items[] = array(
'identifier' => $identifier,
'href' => $href,
'type' => $type,
'scorm_type' => $scorm_type,
);
}
}
}
}
return $items;
}
/**
* Combine resources and SCO data.
*
* Update SCO data to include resource information (if necessary). Return the updated
* SCO list.
*
* @param array $scos
* @param array $resources
*
* @return array
*/
function opigno_scorm_combine_manifest_sco_and_resources($scos, $resources) {
if (!empty($scos)) {
foreach ($scos as &$sco) {
// If the SCO has a resource identifier ("identifierref"),
// we need to combine them.
if (!empty($sco['resource_identifier'])) {
// Check all resources, and break when the correct one is found.
foreach ($resources as $resource) {
if (!empty($resource['identifier']) && $resource['identifier'] == $sco['resource_identifier']) {
// If the SCO has no launch attribute, get the resource href.
if (!empty($resource['href']) && empty($sco['launch'])) {
$sco['launch'] = $resource['href'];
}
// Set the SCO type, if available.
if (!empty($resource['type']) && empty($sco['type'])) {
$sco['type'] = $resource['type'];
}
// Set the SCO scorm type, if available.
if (!empty($resource['scorm_type']) && empty($sco['scorm_type'])) {
$sco['scorm_type'] = $resource['scorm_type'];
}
break;
}
}
}
}
}
else {
if (!empty($resources)) {
// Init scos array.
$scos = array();
foreach ($resources as $resource) {
$sco = array();
// Add lunch key for the sco.
if (!empty($resource['href'])) {
$sco['launch'] = $resource['href'];
}
// Add type key for the sco.
if (!empty($resource['type'])) {
$sco['type'] = $resource['type'];
}
// Add scorm type key for the sco.
if (!empty($resource['scorm_type'])) {
$sco['scorm_type'] = $resource['scorm_type'];
}
// Add scorm type key for the sco.
if (empty($resource['title']) && !empty($resource['identifier'])) {
$sco['title'] = $resource['identifier'];
}
// Set identifier and default values.
$sco['identifier'] = $resource['identifier'];
$sco['parent_identifier'] = 0;
$sco['weight'] = 0;
// Add created sco to scos list.
$scos[] = $sco;
}
}
}
return $scos;
}Functions
Name |
Description |
|---|---|
| opigno_scorm_combine_manifest_sco_and_resources | Combine resources and SCO data. |
| opigno_scorm_extract | Extract the SCORM package from the file. |
| opigno_scorm_extract_item_sequencing_control_modes | Extract the manifest SCO item sequencing control modes. |
| opigno_scorm_extract_item_sequencing_objectives | Extract the manifest SCO item sequencing objective. |
| opigno_scorm_extract_manifest_data | Extract the manifest data. |
| opigno_scorm_extract_manifest_metadata | Extract the manifest metadata. |
| opigno_scorm_extract_manifest_resources | Extract the manifest SCO resources. |
| opigno_scorm_extract_manifest_scos | Extract the manifest SCO items. |
| _opigno_scorm_extract_manifest_scos_items | Helper function to recursively extract the manifest SCO items. |