views_data_export_plugin_display_export.inc in Views data export 7
Same filename and directory in other branches
Contains the bulk export display plugin.
This allows views to be rendered in parts by batch API.
File
plugins/views_data_export_plugin_display_export.incView source
<?php
/**
* @file
* Contains the bulk export display plugin.
*
* This allows views to be rendered in parts by batch API.
*/
/**
* The plugin that batches its rendering.
*
* We are based on a feed display for compatibility.
*
* @ingroup views_display_plugins
*/
class views_data_export_plugin_display_export extends views_plugin_display_feed {
/**
* The batched execution state of the view.
*/
public $batched_execution_state;
/**
* The alias of the weight field in the index table.
*/
var $weight_field_alias = '';
/**
* A map of the index column names to the expected views aliases.
*/
var $field_aliases = array();
/**
* Private variable that stores the filename to save the results to.
*/
var $_output_file = '';
var $views_data_export_cached_view_loaded;
var $errors = array();
/**
* Return the type of styles we require.
*/
function get_style_type() {
return 'data_export';
}
/**
* Return the sections that can be defaultable.
*/
function defaultable_sections($section = NULL) {
if (in_array($section, array(
'items_per_page',
'offset',
'use_pager',
'pager_element',
))) {
return FALSE;
}
return parent::defaultable_sections($section);
}
/**
* Define the option for this view.
*/
function option_definition() {
$options = parent::option_definition();
$options['use_batch'] = array(
'default' => TRUE,
);
$options['items_per_page'] = array(
'default' => '0',
);
$options['style_plugin']['default'] = 'views_data_export_csv';
if (isset($options['defaults']['default']['items_per_page'])) {
$options['defaults']['default']['items_per_page'] = FALSE;
}
return $options;
}
/**
* Provide the summary for page options in the views UI.
*
* This output is returned as an array.
*/
function options_summary(&$categories, &$options) {
// It is very important to call the parent function here:
parent::options_summary($categories, $options);
$categories['page']['title'] = t('Export settings');
$options['use_batch'] = array(
'category' => 'page',
'title' => t('Batched export'),
'value' => $this
->get_option('use_batch') ? t('Yes') : t('No'),
);
}
/**
* Provide the default form for setting options.
*/
function options_form(&$form, &$form_state) {
// It is very important to call the parent function here:
parent::options_form($form, $form_state);
switch ($form_state['section']) {
case 'use_batch':
$form['#title'] .= t('Batched export');
$form['use_batch'] = array(
'#type' => 'radios',
'#description' => t(''),
'#default_value' => $this
->get_option('use_batch'),
'#options' => array(
TRUE => t('Export data in small segments to build a complete export. Recommended for large exports sets (1000+ rows)'),
FALSE => t('Export data all in one segment. Possible time and memory limit issues.'),
),
);
break;
}
}
/**
* Save the options from the options form.
*/
function options_submit(&$form, &$form_state) {
// It is very important to call the parent function here:
parent::options_submit($form, $form_state);
switch ($form_state['section']) {
case 'use_batch':
$this
->set_option('use_batch', $form_state['values']['use_batch']);
break;
}
}
/**
* Determine if this view should run as a batch or not.
*/
function is_batched() {
// The source of this option may change in the future.
return $this
->get_option('use_batch') && empty($this->view->live_preview);
}
/**
* Add HTTP headers for the file export.
*/
function add_http_headers() {
// Ask the style plugin to add any HTTP headers if it wants.
if (method_exists($this->view->style_plugin, 'add_http_headers')) {
$this->view->style_plugin
->add_http_headers();
}
}
/**
* Execute this display handler.
*
* This is the main entry point for this display. We do different things based
* on the stage in the rendering process.
*
* If we are being called for the very first time, the user has usually just
* followed a link to our view. For this phase we:
* - Register a new batched export with our parent module.
* - Build and execute the view, redirecting the output into a temporary table.
* - Set up the batch.
*
* If we are being called during batch processing we:
* - Set up our variables from the context into the display.
* - Call the rendering layer.
* - Return with the appropriate progress value for the batch.
*
* If we are being called after the batch has completed we:
* - Remove the index table.
* - Show the complete page with a download link.
* - Transfer the file if the download link was clicked.
*/
function execute() {
if (!$this
->is_batched()) {
return parent::execute();
}
// Try and get a batch context if possible.
$eid = !empty($_GET['eid']) ? $_GET['eid'] : (!empty($this->batched_execution_state->eid) ? $this->batched_execution_state->eid : FALSE);
if ($eid) {
$this->batched_execution_state = views_data_export_get($eid);
}
// First time through
if (empty($this->batched_execution_state)) {
$output = $this
->execute_initial();
}
// Call me on the cached version of this view please
// This allows this view to be programatically executed with nothing
// more than the eid in $_GET in order for it to execute the next chunk
// TODO: What is going on here?
/*
Jamsilver tells me this might be useful one day.
if (!$this->views_data_export_cached_view_loaded) {
$view = views_data_export_view_retrieve($this->batched_execution_state->eid);
$view->set_display($this->view->current_display);
$view->display_handler->batched_execution_state->eid = $this->batched_execution_state->eid;
$view->display_handler->views_data_export_cached_view_loaded = TRUE;
$ret = $view->execute_display($this->view->current_display);
$this->batched_execution_state = &$view->display_handler->batched_execution_state;
return $ret;
}*/
// Last time through
if ($this->batched_execution_state->batch_state == VIEWS_DATA_EXPORT_FINISHED) {
$output = $this
->execute_final();
}
else {
$output = $this
->execute_normal();
}
//Ensure any changes we made to the database sandbox are saved
views_data_export_update($this->batched_execution_state);
return $output;
}
/**
* Initializes the whole export process and starts off the batch process.
*
* Page execution will be ended at the end of this function.
*/
function execute_initial() {
// Register this export with our central table - get a unique eid
// Also store our view in a cache to be retrieved with each batch call
$this->batched_execution_state = views_data_export_new($this->view->name, $this->view->current_display, $this
->outputfile_create());
views_data_export_view_store($this->batched_execution_state->eid, $this->view);
// We need to build the index right now, before we lose $_GET etc.
$this
->initialize_index();
//$this->batched_execution_state->fid = $this->outputfile_create();
// Initialize the progress counter
$this->batched_execution_state->sandbox['max'] = db_query('SELECT COUNT(*) FROM {' . $this
->index_tablename() . '}')
->fetchField();
// Record the time we started.
list($usec, $sec) = explode(' ', microtime());
$this->batched_execution_state->sandbox['started'] = (double) $usec + (double) $sec;
// Build up our querystring for the final page callback.
$querystring = array(
'eid' => $this->batched_execution_state->eid,
);
// If we were attached to another view, grab that for the final URL.
if (!empty($_GET['attach']) && isset($this->view->display[$_GET['attach']])) {
// Get the path of the attached display:
$querystring['return-url'] = $this->view->display[$_GET['attach']]->handler
->get_path();
}
//Set the batch off
$batch = array(
'operations' => array(
array(
'_views_data_export_batch_process',
array(
$this->batched_execution_state->eid,
$this->view->current_display,
),
),
),
'title' => t('Building export'),
'init_message' => t('Export is starting up.'),
'progress_message' => t('Exporting @percentage% complete,'),
'error_message' => t('Export has encountered an error.'),
);
// We do not return, so update database sandbox now
views_data_export_update($this->batched_execution_state);
$final_destination = $this
->get_option('path');
// Provide a way in for others at this point
// e.g. Drush to grab this batch and yet execute it in
// it's own special way
$batch['view_name'] = $this->view->name;
$batch['display_id'] = $this->view->current_display;
$batch['eid'] = $this->batched_execution_state->eid;
$batch_redirect = array(
$final_destination,
array(
'query' => $querystring,
),
);
drupal_alter('views_data_export_batch', $batch, $batch_redirect);
// Modules may have cleared out $batch, indicating that we shouldn't process further.
if (!empty($batch)) {
batch_set($batch);
// batch_process exits
batch_process($batch_redirect);
}
}
/**
* Compiles the next chunk of the output file
*/
function execute_normal() {
// Pass through to our render method,
$output = $this->view
->render();
// Append what was rendered to the output file.
$this
->outputfile_write($output);
// Store for convenience.
$state =& $this->batched_execution_state;
$sandbox =& $state->sandbox;
// Update progress measurements & move our state forward
switch ($state->batch_state) {
case VIEWS_DATA_EXPORT_BODY:
// Remove rendered results from our index
if (count($this->view->result) && $sandbox['weight_field_alias']) {
$last = end($this->view->result);
db_delete($this
->index_tablename())
->condition($sandbox['weight_field_alias'], $last->{$sandbox['weight_field_alias']}, '<=')
->execute();
// Update progress.
$progress = db_query('SELECT COUNT(*) FROM {' . $this
->index_tablename() . '}')
->fetchField();
// TODO: These next few lines are messy, clean them up.
$progress = 0.99 - $progress / $sandbox['max'] * 0.99;
$progress = (int) floor($progress * 100000);
$progress = $progress / 100000;
$sandbox['finished'] = $progress;
}
else {
// No more results.
$progress = 0.99;
$state->batch_state = VIEWS_DATA_EXPORT_FOOTER;
}
break;
case VIEWS_DATA_EXPORT_HEADER:
$sandbox['finished'] = 0;
$state->batch_state = VIEWS_DATA_EXPORT_BODY;
break;
case VIEWS_DATA_EXPORT_FOOTER:
$sandbox['finished'] = 1;
$state->batch_state = VIEWS_DATA_EXPORT_FINISHED;
break;
}
// Create a more helpful exporting message.
$sandbox['message'] = $this
->compute_time_remaining($sandbox['started'], $sandbox['finished']);
}
/**
* Renders the final page
* We should be free of the batch at this point
*/
function execute_final() {
// Should we download the file.
if (!empty($_GET['download'])) {
// This next method will exit.
$this
->transfer_file();
}
else {
// Remove the index table.
$this
->remove_index();
return $this
->render_complete();
}
}
/**
* Render the display.
*
* We basically just work out if we should be rendering the header, body or
* footer and call the appropriate functions on the style plugins.
*/
function render() {
if (!$this
->is_batched()) {
$result = parent::render();
if (empty($this->view->live_preview)) {
$this
->add_http_headers();
}
return $result;
}
$this->view
->build();
switch ($this->batched_execution_state->batch_state) {
case VIEWS_DATA_EXPORT_BODY:
$output = $this->view->style_plugin
->render_body();
break;
case VIEWS_DATA_EXPORT_HEADER:
$output = $this->view->style_plugin
->render_header();
break;
case VIEWS_DATA_EXPORT_FOOTER:
$output = $this->view->style_plugin
->render_footer();
break;
}
return $output;
}
/**
* Trick views into thinking that we have executed the query and got results.
*
* We are called in the build phase of the view, but short circuit straight to
* getting the results and making the view think it has already executed the
* query.
*/
function query() {
if (!$this
->is_batched()) {
return parent::query();
}
// Make the query distinct if the option was set.
if ($this
->get_option('distinct')) {
$this->view->query
->set_distinct();
}
if (!empty($this->batched_execution_state->batch_state) && !empty($this->batched_execution_state->sandbox['weight_field_alias'])) {
switch ($this->batched_execution_state->batch_state) {
case VIEWS_DATA_EXPORT_BODY:
case VIEWS_DATA_EXPORT_HEADER:
case VIEWS_DATA_EXPORT_FOOTER:
// Tell views its been executed.
$this->view->executed = TRUE;
// Grab our results from the index, and push them into the view result.
// TODO: Handle external databases.
$result = db_query_range('SELECT * FROM {' . $this
->index_tablename() . '} ORDER BY ' . $this->batched_execution_state->sandbox['weight_field_alias'] . ' ASC', 0, 100);
$this->view->result = array();
foreach ($result as $item_hashed) {
$item = new stdClass();
// We had to shorten some of the column names in the index, restore
// those now.
foreach ($item_hashed as $hash => $value) {
if (isset($this->batched_execution_state->sandbox['field_aliases'][$hash])) {
$item->{$this->batched_execution_state->sandbox['field_aliases'][$hash]} = $value;
}
else {
$item->{$hash} = $value;
}
}
// Push the restored $item in the views result array.
$this->view->result[] = $item;
}
break;
}
}
}
/**
* Render the 'Export Finished' page with the link to the file on it.
*/
function render_complete() {
$return_path = empty($_GET['return-url']) ? '' : $_GET['return-url'];
$query = array(
'download' => 1,
'eid' => $this->batched_execution_state->eid,
);
return theme('views_data_export_complete_page', array(
'file' => url($this
->get_option('path'), array(
'query' => $query,
)),
'errors' => $this->errors,
'return_url' => $return_path,
));
}
/**
* TBD - What does 'preview' mean for bulk exports?
* According to doc:
* "Fully render the display for the purposes of a live preview or
* some other AJAXy reason. [views_plugin_display.inc:1877]"
*
* Not sure it makes sense for Bulk exports to be previewed in this manner?
* We need the user's full attention to run the batch. Suggestions:
* 1) Provide a link to execute the view?
* 2) Provide a link to the last file we generated??
* 3) Show a table of the first 20 results?
*/
function preview() {
if (!$this
->is_batched()) {
// Can replace with return parent::preview() when views 2.12 lands.
if (!empty($this->view->live_preview)) {
// Change the items per page:
$this->view
->set_items_per_page(20);
return '<p>' . t('A maximum of 20 items will be shown here, all results will be shown on export.') . '</p><pre>' . check_plain($this->view
->render()) . '</pre>';
}
return $this->view
->render();
}
return '';
}
/**
* Transfer the output file to the client.
*/
function transfer_file() {
// Build the view so we can set the headers.
$this->view
->build();
// Set the headers.
$this
->add_http_headers();
file_transfer($this
->outputfile_path(), array());
}
/**
* Called on export initialization.
*
* Modifies the view query to insert the results into a table, which we call
* the 'index', this means we essentially have a snapshot of the results,
* which we can then take time over rendering.
*
* This method is essentially all the best bits of the view::execute() method.
*/
protected function initialize_index() {
$view =& $this->view;
// Get views to build the query.
$view
->build();
// Change the query object to use our custom one.
$query = new views_data_export_plugin_query_default_batched();
// Copy the query over:
foreach ($view->query as $property => $value) {
$query->{$property} = $value;
}
// Replace the query object.
$view->query = $query;
$view
->execute();
}
/**
* Given a view, construct an map of hashed aliases to aliases.
*
* The keys of the returned array will have a maximum length of 33 characters.
*/
function field_aliases_create(&$view) {
$all_aliases = array();
foreach ($view->query->fields as $field) {
if (strlen($field['alias']) > 32) {
$all_aliases['a' . md5($field['alias'])] = $field['alias'];
}
else {
$all_aliases[$field['alias']] = $field['alias'];
}
}
return $all_aliases;
}
/**
* Create an alias for the weight field in the index.
*
* This method ensures that it isn't the same as any other alias in the
* supplied view's fields.
*/
function _weight_alias_create(&$view) {
$alias = 'vde_weight';
$all_aliases = array();
foreach ($view->query->fields as $field) {
$all_aliases[] = $field['alias'];
}
// Keep appending '_' until we are unique.
while (in_array($alias, $all_aliases)) {
$alias .= '_';
}
return $alias;
}
/**
* Remove the index.
*/
function remove_index() {
$ret = array();
if (db_table_exists($this
->index_tablename())) {
db_drop_table($this
->index_tablename());
}
}
/**
* Return the name of the unique table to store the index in.
*/
function index_tablename() {
return VIEWS_DATA_EXPORT_INDEX_TABLE_PREFIX . $this->batched_execution_state->eid;
}
/**
* Get the output file path.
*/
function outputfile_path() {
if (empty($this->_output_file) && !empty($this->batched_execution_state->fid)) {
// Return the filename associated with this file.
$this->_output_file = $this
->file_load($this->batched_execution_state->fid);
}
return $this->_output_file->uri;
}
/**
* Called on export initialization
* Creates the output file, registers it as a temporary file with Drupal
* and returns the fid
*/
protected function outputfile_create() {
$dir = 'temporary://views_plugin_display';
// Make sure the directory exists first.
if (!file_prepare_directory($dir, FILE_CREATE_DIRECTORY | FILE_MODIFY_PERMISSIONS)) {
$this
->abort_export(t('Could not create temporary directory for result export (@dir). Check permissions.', array(
'@dir' => $dir,
)));
}
$path = drupal_tempnam($dir, 'views_data_export');
// Save the file into the DB.
$file = $this
->file_save_file($path);
return $file->fid;
}
/**
* Write to the output file.
*/
protected function outputfile_write($string) {
$output_file = $this
->outputfile_path();
if (file_put_contents($output_file, $string, FILE_APPEND) === FALSE) {
$this
->abort_export(t('Could not write to temporary output file for result export (@file). Check permissions.', array(
'@file' => $output_file,
)));
}
}
function abort_export($errors) {
// Just cause the next batch to do the clean-up
if (!is_array($errors)) {
$errors = array(
$errors,
);
}
foreach ($errors as $error) {
drupal_set_message($error . ' [' . t('Export Aborted') . ']', 'error');
}
$this->batched_execution_state->batch_state = VIEWS_DATA_EXPORT_FINISHED;
}
/**
* Load a file from the database.
*
* @param $fid
* A numeric file id or string containing the file path.
* @return
* A file object.
*/
function file_load($fid) {
return file_load($fid);
}
/**
* Save a file into a file node after running all the associated validators.
*
* This function is usually used to move a file from the temporary file
* directory to a permanent location. It may be used by import scripts or other
* modules that want to save an existing file into the database.
*
* @param $filepath
* The local file path of the file to be saved.
* @return
* An array containing the file information, or 0 in the event of an error.
*/
function file_save_file($filepath) {
return file_save_data('', $filepath);
}
/**
* Helper function that computes the time remaining
*/
function compute_time_remaining($started, $finished) {
list($usec, $sec) = explode(' ', microtime());
$now = (double) $usec + (double) $sec;
$diff = round($now - $started, 0);
// So we've taken $diff seconds to get this far.
if ($finished > 0) {
$estimate_total = $diff / $finished;
$stamp = max(1, $estimate_total - $diff);
// Round up to nearest 30 seconds.
$stamp = ceil($stamp / 30) * 30;
// Set the message in the batch context.
return t('Time remaining: about @interval.', array(
'@interval' => format_interval($stamp),
));
}
}
}
class views_data_export_plugin_query_default_batched extends views_plugin_query_default {
/**
* Executes the query and fills the associated view object with according
* values.
*
* Values to set: $view->result, $view->total_rows, $view->execute_time,
* $view->current_page.
*/
function execute(&$view) {
$display_handler =& $view->display_handler;
$external = FALSE;
// Whether this query will run against an external database.
$query = $view->build_info['query'];
$count_query = $view->build_info['count_query'];
$query
->addMetaData('view', $view);
$count_query
->addMetaData('view', $view);
if (empty($this->options['disable_sql_rewrite'])) {
$base_table_data = views_fetch_data($this->base_table);
if (isset($base_table_data['table']['base']['access query tag'])) {
$access_tag = $base_table_data['table']['base']['access query tag'];
$query
->addTag($access_tag);
$count_query
->addTag($access_tag);
}
}
$items = array();
if ($query) {
$additional_arguments = module_invoke_all('views_query_substitutions', $view);
// Build the count query. db_select::countQuery does not work with groupby.
$count_query = $count_query
->countQuery();
// $count_query->distinct = FALSE;
// Add additional arguments as a fake condition.
// XXX: this doesn't work... because PDO mandates that all bound arguments
// are used on the query. TODO: Find a better way to do this.
if (!empty($additional_arguments)) {
// $query->where('1 = 1', $additional_arguments);
// $count_query->where('1 = 1', $additional_arguments);
}
// Detect an external database.
if (isset($view->base_database)) {
db_set_active($view->base_database);
$external = TRUE;
}
$start = microtime(TRUE);
if ($this->pager
->use_count_query() || !empty($view->get_total_rows)) {
$this->pager
->execute_count_query($count_query);
}
// Let the pager modify the query to add limits.
$this->pager
->pre_execute($query);
if (!empty($this->limit) || !empty($this->offset)) {
// We can't have an offset without a limit, so provide a very large limit instead.
$limit = intval(!empty($this->limit) ? $this->limit : 999999);
$offset = intval(!empty($this->offset) ? $this->offset : 0);
$query
->range($offset, $limit);
}
try {
// The $query is final and ready to go, we are going to redirect it to
// become an insert into our table, sneaky!
// Our query will look like:
// CREATE TABLE {idx} SELECT @row := @row + 1 AS weight_alias, cl.* FROM
// (-query-) AS cl, (SELECT @row := 0) AS r
// We do some magic to get the row count.
$display_handler->batched_execution_state->sandbox['weight_field_alias'] = $display_handler
->_weight_alias_create($view);
$display_handler->batched_execution_state->sandbox['field_aliases'] = $display_handler
->field_aliases_create($view);
$select_aliases = array();
foreach ($display_handler->batched_execution_state->sandbox['field_aliases'] as $hash => $alias) {
$select_aliases[] = "cl.{$alias} AS {$hash}";
}
// TODO: this could probably be replaced with a query extender and new query type.
$args = $query
->getArguments();
$insert_query = 'CREATE TABLE {' . $display_handler
->index_tablename() . '} SELECT @row := @row + 1 AS ' . $display_handler->batched_execution_state->sandbox['weight_field_alias'] . ', ' . implode(', ', $select_aliases) . ' FROM (' . (string) $query . ') AS cl, (SELECT @row := 0) AS r';
db_query($insert_query, $args);
$view->result = array();
$this->pager
->post_execute($view->result);
if ($this->pager
->use_pager()) {
$view->total_rows = $this->pager
->get_total_items();
}
// Now create an index for the weight field, otherwise the queries on the
// index will take a long time to execute.
db_add_unique_key($display_handler
->index_tablename(), $display_handler->batched_execution_state->sandbox['weight_field_alias'], array(
$display_handler->batched_execution_state->sandbox['weight_field_alias'],
));
} catch (Exception $e) {
$view->result = array();
debug('Exception: ' . $e
->getMessage());
}
if ($external) {
db_set_active();
}
}
$view->execute_time = microtime(TRUE) - $start;
}
}Classes
Name |
Description |
|---|---|
| views_data_export_plugin_display_export | The plugin that batches its rendering. |
| views_data_export_plugin_query_default_batched |