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foreach (func_get_args() as $Q) {
$this->constraints[] = $Q instanceof Q ? $Q->negate() : Q::not($Q);
/**
* Add a path constraint for the query. This is different from ::filter
* in that the constraint is added to a join clause which is normally
* built from the model meta data. The ::filter() method on the other
* hand adds the constraint to the where clause. This is generally useful
* for aggregate queries and left join queries where multiple rows might
* match a filter in the where clause and would produce incorrect results.
*
* Example:
* Find users with personal email hosted with gmail.
* >>> $Q = User::objects();
* >>> $Q->constrain(['user__emails' => new Q(['type' => 'personal']))
* >>> $Q->filter(['user__emails__address__contains' => '@gmail.com'])
*/
function constrain() {
foreach (func_get_args() as $I) {
foreach ($I as $path => $Q) {
if (!is_array($Q) && !$Q instanceof Q) {
// ->constrain(array('field__path__op' => val));
$Q = array($path => $Q);
list(, $path) = SqlCompiler::splitCriteria($path);
$path = implode('__', $path);
}
$this->path_constraints[$path][] = $Q instanceof Q ? $Q : Q::all($Q);
}
}
return $this;
}
function defer() {
foreach (func_get_args() as $f)
$this->defer[$f] = true;
return $this;
}
function order_by($order, $direction=false) {
if ($order === false)
return $this->options(array('nosort' => true));
$args = func_get_args();
if (in_array($direction, array(self::ASC, self::DESC))) {
$args = array($args[0]);
}
else
$direction = false;
$new = is_array($order) ? $order : $args;
if ($direction) {
foreach ($new as $i=>$x) {
$new[$i] = array($x, $direction);
}
}
$this->ordering = array_merge($this->ordering, $new);
function getSortFields() {
$ordering = $this->ordering;
if ($this->extra['order_by'])
$ordering = array_merge($ordering, $this->extra['order_by']);
return $ordering;
}
function lock($how=false) {
$this->lock = $how ?: self::LOCK_EXCLUSIVE;
return $this;
}
function limit($count) {
$this->limit = $count;
return $this;
}
function offset($at) {
$this->offset = $at;
return $this;
}
function isWindowed() {
return $this->limit || $this->offset || (count($this->values) + count($this->annotations) + @count($this->extra['select'])) > 1;
function select_related() {
$this->related = array_merge($this->related, func_get_args());
return $this;
}
function extra(array $extra) {
foreach ($extra as $section=>$info) {
$this->extra[$section] = array_merge($this->extra[$section] ?: array(), $info);
}
return $this;
}
function distinct() {
foreach (func_get_args() as $D)
$this->distinct[] = $D;
return $this;
}
function models() {
$this->iterator = 'ModelInstanceManager';
$this->values = $this->related = array();
return $this;
}
foreach (func_get_args() as $A)
$this->values[$A] = $A;
// This disables related models
$this->related = false;
function values_flat() {
$this->values = func_get_args();
$this->iterator = 'FlatArrayIterator';
// This disables related models
$this->related = false;
function copy() {
return clone $this;
}
function all() {
return $this->getIterator()->asArray();
}
$list = $this->limit(1)->all();
/**
* one
*
* Finds and returns a single model instance based on the criteria in
* this QuerySet instance.
*
* Throws:
* DoesNotExist - if no such model exists with the given criteria
* ObjectNotUnique - if more than one model matches the given criteria
*
* Returns:
* (Object<Model>) a single instance of the sought model is guarenteed.
* If no such model or multiple models exist, an exception is thrown.
*/
function one() {
$list = $this->all();
if (count($list) == 0)
throw new DoesNotExist();
elseif (count($list) > 1)
throw new ObjectNotUnique('One object was expected; however '
.'multiple objects in the database matched the query. '
.sprintf('In fact, there are %d matching objects.', count($list))
);
// Defer to the iterator if fetching already started
if (isset($this->_iterator)) {
return $this->_iterator->count();
}
elseif (isset($this->count)) {
return $this->count;
$class = $this->compiler;
$compiler = new $class();
return $this->_count = $compiler->compileCount($this);
function toSql($compiler, $model, $alias=false) {
// FIXME: Force root model of the compiler to $model
$exec = $this->getQuery(array('compiler' => get_class($compiler),
'parent' => $compiler, 'subquery' => true));
// Rewrite the parameter numbers so they fit the parameter numbers
// of the current parameters of the $compiler
$sql = preg_replace_callback("/:(\d+)/",
function($m) use ($compiler, $exec) {
$compiler->params[] = $exec->params[$m[1]-1];
return ':'.count($compiler->params);
}, $exec->sql);
return "({$sql})".($alias ? " AS {$alias}" : '');
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/**
* exists
*
* Determines if there are any rows in this QuerySet. This can be
* achieved either by evaluating a SELECT COUNT(*) query or by
* attempting to fetch the first row from the recordset and return
* boolean success.
*
* Parameters:
* $fetch - (bool) TRUE if a compile and fetch should be attempted
* instead of a SELECT COUNT(*). This would be recommended if an
* accurate count is not required and the records would be fetched
* if this method returns TRUE.
*
* Returns:
* (bool) TRUE if there would be at least one record in this QuerySet
*/
function exists($fetch=false) {
if ($fetch) {
return (bool) $this[0];
}
return $this->count() > 0;
}
function annotate($annotations) {
if (!is_array($annotations))
$annotations = func_get_args();
foreach ($annotations as $name=>$A) {
if (is_int($name))
$name = $A->getFieldName();
$A->setAlias($name);
}
function aggregate($annotations) {
// Aggregate works like annotate, except that it sets up values
// fetching which will disable model creation
$this->annotate($annotations);
// Disable other fields from being fetched
$this->aggregated = true;
$this->related = false;
return $this;
}
function options($options) {
$this->options = array_merge($this->options, $options);
return $this;
}
function countSelectFields() {
$count = count($this->values) + count($this->annotations);
if (isset($this->extra['select']))
foreach (@$this->extra['select'] as $S)
$count += count($S);
return $count;
}
function union(QuerySet $other, $all=true) {
// Values and values_list _must_ match for this to work
if ($this->countSelectFields() != $other->countSelectFields())
throw new OrmException('Union queries must have matching values counts');
// TODO: Clear OFFSET and LIMIT in the $other query
$this->chain[] = array($other, $all);
return $this;
}
function delete() {
$class = $this->compiler;
$compiler = new $class();
// XXX: Mark all in-memory cached objects as deleted
$ex = $compiler->compileBulkDelete($this);
$ex->execute();
return $ex->affected_rows();
}
function update(array $what) {
$class = $this->compiler;
$compiler = new $class;
$ex = $compiler->compileBulkUpdate($this, $what);
$ex->execute();
return $ex->affected_rows();
}
function __clone() {
unset($this->_iterator);
unset($this->query);
// IteratorAggregate interface
function getIterator() {
$class = $this->iterator;
$this->_iterator = new $class($this);
return $this->_iterator;
}
// ArrayAccess interface
function offsetExists($offset) {
return $this->getIterator()->offsetExists($offset);
}
function offsetGet($offset) {
return $this->getIterator()->offsetGet($offset);
}
function offsetUnset($a) {
throw new Exception(__('QuerySet is read-only'));
throw new Exception(__('QuerySet is read-only'));
return (string) $this->getQuery();
function getQuery($options=array()) {
if (isset($this->query))
return $this->query;
// Load defaults from model
$model = $this->model;
$meta = $model::getMeta();
$options += $this->options;
if ($options['nosort'])
$query->ordering = array();
elseif (!$query->ordering && $meta['ordering'])
$query->ordering = $meta['ordering'];
if (false !== $query->related && !$query->values && $meta['select_related'])
$query->related = $meta['select_related'];
if (!$query->defer && $meta['defer'])
$query->defer = $meta['defer'];
$class = $options['compiler'] ?: $this->compiler;
$compiler = new $class($options);
$this->query = $compiler->compileSelect($query);
/**
* Fetch a model class which can be used to render the QuerySet as a
* subquery to be used as a JOIN.
*/
function asView() {
$unique = spl_object_hash($this);
$classname = "QueryView{$unique}";
if (class_exists($classname))
return $classname;
$class = <<<EOF
class {$classname} extends VerySimpleModel {
static \$meta = array(
'view' => true,
);
static \$queryset;
static function getQuery(\$compiler) {
return ' ('.static::\$queryset->getQuery().') ';
}
static function getSqlAddParams(\$compiler) {
return static::\$queryset->toSql(\$compiler, self::\$queryset->model);
}
EOF;
eval($class); // Ugh
$classname::$queryset = $this;
return $classname;
}
function serialize() {
$info = get_object_vars($this);
unset($info['query']);
unset($info['limit']);
unset($info['offset']);
unset($info['_iterator']);
return serialize($info);
}
function unserialize($data) {
$data = unserialize($data);
foreach ($data as $name => $val) {
$this->{$name} = $val;
}
}
class DoesNotExist extends Exception {}
class ObjectNotUnique extends Exception {}
abstract class ResultSet implements Iterator, ArrayAccess, Countable {
var $resource;
var $position = 0;
var $queryset;
function __construct($queryset=false) {
$this->queryset = $queryset;
if ($queryset) {
$this->model = $queryset->model;
function prime() {
if (!isset($this->resource) && $this->queryset)
$this->resource = $this->queryset->getQuery();
}
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abstract function fillTo($index);
function asArray() {
$this->fillTo(PHP_INT_MAX);
return $this->cache;
}
// Iterator interface
function rewind() {
$this->position = 0;
}
function current() {
$this->fillTo($this->position);
return $this->cache[$this->position];
}
function key() {
return $this->position;
}
function next() {
$this->position++;
}
function valid() {
$this->fillTo($this->position);
return count($this->cache) > $this->position;
}
// ArrayAccess interface
function offsetExists($offset) {
$this->fillTo($offset);
return $this->position >= $offset;
}
function offsetGet($offset) {
$this->fillTo($offset);
return $this->cache[$offset];
}
function offsetUnset($a) {
throw new Exception(sprintf(__('%s is read-only'), get_class($this)));
}
function offsetSet($a, $b) {
throw new Exception(sprintf(__('%s is read-only'), get_class($this)));
}
// Countable interface
function count() {
return count($this->asArray());
}
}
class ModelInstanceManager extends ResultSet {
var $model;
var $map;
static $objectCache = array();
function cache($model) {
$key = sprintf('%s.%s',
$model::$meta->model, implode('.', $model->get('pk')));
self::$objectCache[$key] = $model;
}
/**
* uncache
*
* Drop the cached reference to the model. If the model is deleted
* database-side. Lookups for the same model should not be short
* circuited to retrieve the cached reference.
*/
static function uncache($model) {
$key = sprintf('%s.%s',
$model::$meta->model, implode('.', $model->pk));
unset(self::$objectCache[$key]);
}
static function flushCache() {
self::$objectCache = array();
}
static function checkCache($modelClass, $fields) {
$key = $modelClass::$meta->model;
foreach ($modelClass::getMeta('pk') as $f)
$key .= '.'.$fields[$f];
return @self::$objectCache[$key];
}
/**
* getOrBuild
*
* Builds a new model from the received fields or returns the model
* already stashed in the model cache. Caching helps to ensure that
* multiple lookups for the same model identified by primary key will
* fetch the exact same model. Therefore, changes made to the model
* anywhere in the project will be reflected everywhere.
*
* For annotated models (models build from querysets with annotations),
* the built or cached model is wrapped in an AnnotatedModel instance.
* The annotated fields are in the AnnotatedModel instance and the
* database-backed fields are managed by the Model instance.
*/
function getOrBuild($modelClass, $fields, $cache=true) {
// Check for NULL primary key, used with related model fetching. If
// the PK is NULL, then consider the object to also be NULL
foreach ($modelClass::getMeta('pk') as $pkf) {
if (!isset($fields[$pkf])) {
return null;
}
}
$annotations = $this->queryset->annotations;
$extras = array();
// For annotations, drop them from the $fields list and add them to
// an $extras list. The fields passed to the root model should only
// be the root model's fields. The annotated fields will be wrapped
// using an AnnotatedModel instance.
if ($annotations && $modelClass == $this->model) {
if (array_key_exists($name, $fields)) {
$extras[$name] = $fields[$name];
unset($fields[$name]);
}
}
}
// Check the cache for the model instance first
if (!($m = self::checkCache($modelClass, $fields))) {
// Construct and cache the object
$m = $modelClass::$meta->newInstance($fields);
// XXX: defer may refer to fields not in this model
$m->__deferred__ = $this->queryset->defer;
$m->__onload();
if ($cache)
$this->cache($m);
}
// Wrap annotations in an AnnotatedModel
if ($extras) {
$m = new AnnotatedModel($m, $extras);
// TODO: If the model has deferred fields which are in $fields,
// those can be resolved here
return $m;
}
/**
* buildModel
*
* This method builds the model including related models from the record
* received. For related recordsets, a $map should be setup inside this
* object prior to using this method. The $map is assumed to have this
* configuration:
*
* array(array(<fieldNames>, <modelClass>, <relativePath>))
*
* Where $modelClass is the name of the foreign (with respect to the
* root model ($this->model), $fieldNames is the number and names of
* fields in the row for this model, $relativePath is the path that
* describes the relationship between the root model and this model,
* 'user__account' for instance.
function buildModel($row) {
// TODO: Traverse to foreign keys
if ($this->map) {
if ($this->model != $this->map[0][1])
throw new OrmException('Internal select_related error');
$offset = 0;
foreach ($this->map as $info) {
@list($fields, $model_class, $path) = $info;
$values = array_slice($row, $offset, count($fields));
$record = array_combine($fields, $values);
if (!$path) {
// Build the root model
$model = $this->getOrBuild($this->model, $record);
$i = 0;
// Traverse the declared path and link the related model
$tail = array_pop($path);
$m = $model;
foreach ($path as $field) {
if (!($m = $m->get($field)))
break;
if ($m)
$m->set($tail, $this->getOrBuild($model_class, $record));
$model = $this->getOrBuild($this->model, $row);
$func = ($this->map) ? 'getRow' : 'getArray';
while ($this->resource && $index >= count($this->cache)) {
if ($row = $this->resource->{$func}()) {
$this->cache[] = $this->buildModel($row);
} else {
$this->resource->close();
$this->resource = false;
function prime() {
parent::prime();
if ($this->resource) {
$this->map = $this->resource->getMap();
}
}
class FlatArrayIterator extends ResultSet {
while ($this->resource && $index >= count($this->cache)) {
if ($row = $this->resource->getRow()) {
} else {
$this->resource->close();
$this->resource = false;
break;
}
}
}
}
class HashArrayIterator extends ResultSet {
function fillTo($index) {
while ($this->resource && $index >= count($this->cache)) {
if ($row = $this->resource->getArray()) {
$this->cache[] = $row;
} else {
$this->resource->close();
$this->resource = false;
break;
}
}
}
}
class InstrumentedList extends ModelInstanceManager {
var $key;
function __construct($fkey, $queryset=false) {
list($model, $this->key) = $fkey;
$queryset = $model::objects()->filter($this->key);
if ($related = $model::getMeta('select_related'))
$queryset->select_related($related);
}
parent::__construct($queryset);
function add($object, $at=false) {
if (!$object || !$object instanceof $this->model)
throw new Exception(sprintf(
'Attempting to add invalid object to list. Expected <%s>, but got <%s>',
$this->model,
get_class($object)
));
foreach ($this->key as $field=>$value)
$object->set($field, $value);
if (!$object->__new__)
$object->save();
if ($at !== false)
$this->cache[$at] = $object;
else
$this->cache[] = $object;
function remove($object, $delete=true) {
if ($delete)
$object->delete();
else
foreach ($this->key as $field=>$value)
$object->set($field, null);
function reset() {
$this->cache = array();
/**
* Slight edit to the standard ::next() iteration method which will skip
* deleted items.
*/
function next() {
do {
parent::next();
}
while ($this->valid() && $this->current()->__deleted__);
}
/**
* Reduce the list to a subset using a simply key/value constraint. New
* items added to the subset will have the constraint automatically
* added to all new items.
*/
function window($constraint) {
$model = $this->model;
$fields = $model::getMeta()->getFieldNames();
$key = $this->key;
foreach ($constraint as $field=>$value) {
if (!is_string($field) || false === in_array($field, $fields))
throw new OrmException('InstrumentedList windowing must be performed on local fields only');
$key[$field] = $value;
}
return new static(array($this->model, $key), $this->filter($constraint));
}
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/**
* Find the first item in the current set which matches the given criteria.
* This would be used in favor of ::filter() which might trigger another
* database query. The criteria is intended to be quite simple and should
* not traverse relationships which have not already been fetched.
* Otherwise, the ::filter() or ::window() methods would provide better
* performance.
*
* Example:
* >>> $a = new User();
* >>> $a->roles->add(Role::lookup(['name' => 'administator']));
* >>> $a->roles->findFirst(['roles__name__startswith' => 'admin']);
* <Role: administrator>
*/
function findFirst(array $criteria) {
foreach ($this as $record) {
$matches = true;
foreach ($criteria as $field=>$check) {
if (!SqlCompiler::evaluate($record, $field, $check)) {
$matches = false;
break;
}
}
if ($matches)
return $record;
}
}
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/**
* Sort the instrumented list in place. This would be useful to change the
* sorting order of the items in the list without fetching the list from
* the database again.
*
* Parameters:
* $key - (callable|int) A callable function to produce the sort keys
* or one of the SORT_ constants used by the array_multisort
* function
* $reverse - (bool) true if the list should be sorted descending
*
* Returns:
* This instrumented list for chaining and inlining.
*/
function sort($key=false, $reverse=false) {
// Fetch all records into the cache
$this->asArray();
if (is_callable($key)) {
array_multisort(
array_map($key, $this->cache),
$reverse ? SORT_DESC : SORT_ASC,
$this->cache);
}
elseif ($key) {
array_multisort($this->cache,
$reverse ? SORT_DESC : SORT_ASC, $key);
}
elseif ($reverse) {
rsort($this->cache);
}
else
sort($this->cache);
return $this;
}
/**
* Reverse the list item in place. Returns this object for chaining
*/
function reverse() {
$this->asArray();
array_reverse($this->cache);
return $this;
}
// Save all changes made to any list items
function saveAll() {
foreach ($this as $I)
if (!$I->save())
return false;
return true;
}
// QuerySet delegates
function count() {
return $this->objects()->count();
}
function exists() {
return $this->queryset->exists();
}
function expunge() {
if ($this->queryset->delete())
$this->reset();
function update(array $what) {
return $this->queryset->update($what);
}
// Fetch a new QuerySet
function objects() {
return clone $this->queryset;
function offsetUnset($a) {
$this->fillTo($a);
$this->cache[$a]->delete();
}
function offsetSet($a, $b) {
$this->fillTo($a);
$this->cache[$a]->delete();
$this->add($b, $a);
function __call($what, $how) {
return call_user_func_array(array($this->objects(), $what), $how);
var $joins = array();
var $aliases = array();
var $alias_num = 1;
function __construct($options=false) {
if ($options)
$this->options = array_merge($this->options, $options);
if ($options['subquery'])
$this->alias_num += 150;
}
function getParent() {
return $this->options['parent'];
/**
* Split a criteria item into the identifying pieces: path, field, and
* operator.
*/
static function splitCriteria($criteria) {
static $operators = array(
'exact' => 1, 'isnull' => 1,
'gt' => 1, 'lt' => 1, 'gte' => 1, 'lte' => 1, 'range' => 1,
'contains' => 1, 'like' => 1, 'startswith' => 1, 'endswith' => 1, 'regex' => 1,
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'in' => 1, 'intersect' => 1,
'hasbit' => 1,
);
$path = explode('__', $criteria);
if (!isset($options['table'])) {
$field = array_pop($path);
if (isset($operators[$field])) {
$operator = $field;
$field = array_pop($path);
}
}
return array($field, $path, $operator ?: 'exact');
}
/**
* Check if the values match given the operator.
*
* Throws:
* OrmException - if $operator is not supported
*/
static function evaluate($record, $field, $check) {
static $ops; if (!isset($ops)) { $ops = array(
'exact' => function($a, $b) { return is_string($a) ? strcasecmp($a, $b) == 0 : $a == $b; },
'isnull' => function($a, $b) { return is_null($a) == $b; },
'gt' => function($a, $b) { return $a > $b; },
'gte' => function($a, $b) { return $a >= $b; },
'lt' => function($a, $b) { return $a < $b; },
'lte' => function($a, $b) { return $a <= $b; },
'contains' => function($a, $b) { return stripos($a, $b) !== false; },
'startswith' => function($a, $b) { return stripos($a, $b) === 0; },
'hasbit' => function($a, $b) { return $a & $b == $b; },
); }
list($field, $path, $operator) = self::splitCriteria($field);
if (!isset($ops[$operator]))
throw new OrmException($operator.': Unsupported operator');
if ($path)
$record = $record->getByPath($path);
// TODO: Support Q expressions
return $ops[$operator]($record->get($field), $check);
}
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/**
* Handles breaking down a field or model search descriptor into the
* model search path, field, and operator parts. When used in a queryset
* filter, an expression such as
*
* user__email__hostname__contains => 'foobar'
*
* would be broken down to search from the root model (passed in,
* perhaps a ticket) to the user and email models by inspecting the
* model metadata 'joins' property. The 'constraint' value found there
* will be used to build the JOIN sql clauses.
*
* The 'hostname' will be the field on 'email' model that should be
* compared in the WHERE clause. The comparison should be made using a
* 'contains' function, which in MySQL, might be implemented using
* something like "<lhs> LIKE '%foobar%'"
*
* This function will rely heavily on the pushJoin() function which will
* handle keeping track of joins made previously in the query and
* therefore prevent multiple joins to the same table for the same
* reason. (Self joins are still supported).
*
* Comparison functions supported by this function are defined for each
* respective SqlCompiler subclass; however at least these functions
* should be defined:
*
* function a__function => b
* ----------+------------------------------------------------
* exact | a is exactly equal to b
* gt | a is greater than b
* lte | b is greater than a
* lt | a is less than b
* gte | b is less than a
* ----------+------------------------------------------------
* contains | (string) b is contained within a
* statswith | (string) first len(b) chars of a are exactly b
* endswith | (string) last len(b) chars of a are exactly b
* like | (string) a matches pattern b
* ----------+------------------------------------------------
* in | a is in the list or the nested queryset b
* ----------+------------------------------------------------
* isnull | a is null (if b) else a is not null
*
* If no comparison function is declared in the field descriptor,
* 'exact' is assumed.
*
* Parameters:
* $field - (string) name of the field to join
* $model - (VerySimpleModel) root model for references in the $field
* parameter
* $options - (array) extra options for the compiler
* 'table' => return the table alias rather than the field-name
* 'model' => return the target model class rather than the operator
* 'constraint' => extra constraint for join clause
*
* Returns:
* (mixed) Usually array<field-name, operator> where field-name is the
* name of the field in the destination model, and operator is the
* requestion comparison method.
*/
function getField($field, $model, $options=array()) {
// Break apart the field descriptor by __ (double-underbars). The
// first part is assumed to be the root field in the given model.
// The parts after each of the __ pieces are links to other tables.
// The last item (after the last __) is allowed to be an operator
// specifiction.
list($field, $parts, $op) = static::splitCriteria($field);
$operator = static::$operators[$op];
$rootModel = $model;
// Call pushJoin for each segment in the join path. A new JOIN
// fragment will need to be emitted and/or cached
$joins = array();
$push = function($p, $model) use (&$joins, &$path) {
$J = $model::getMeta('joins');
if (!($info = $J[$p])) {
throw new OrmException(sprintf(
'Model `%s` does not have a relation called `%s`',
$model, $p));
}