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LiskDAO.php
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<?php
/*
* Copyright 2012 Facebook, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* Simple object-authoritative data access object that makes it easy to build
* stuff that you need to save to a database. Basically, it means that the
* amount of boilerplate code (and, particularly, boilerplate SQL) you need
* to write is greatly reduced.
*
* Lisk makes it fairly easy to build something quickly and end up with
* reasonably high-quality code when you're done (e.g., getters and setters,
* objects, transactions, reasonably structured OO code). It's also very thin:
* you can break past it and use MySQL and other lower-level tools when you
* need to in those couple of cases where it doesn't handle your workflow
* gracefully.
*
* However, Lisk won't scale past one database and lacks many of the features
* of modern DAOs like Hibernate: for instance, it does not support joins or
* polymorphic storage.
*
* This means that Lisk is well-suited for tools like Differential, but often a
* poor choice elsewhere. And it is strictly unsuitable for many projects.
*
* Lisk's model is object-authoritative: the PHP class definition is the
* master authority for what the object looks like.
*
* =Building New Objects=
*
* To create new Lisk objects, extend @{class:LiskDAO} and implement
* @{method:establishLiveConnection}. It should return an
* @{class:AphrontDatabaseConnection}; this will tell Lisk where to save your
* objects.
*
* class Dog extends LiskDAO {
*
* protected $name;
* protected $breed;
*
* public function establishLiveConnection() {
* return $some_connection_object;
* }
* }
*
* Now, you should create your table:
*
* lang=sql
* CREATE TABLE dog (
* id int unsigned not null auto_increment primary key,
* name varchar(32) not null,
* breed varchar(32) not null,
* dateCreated int unsigned not null,
* dateModified int unsigned not null
* );
*
* For each property in your class, add a column with the same name to the table
* (see @{method:getConfiguration} for information about changing this mapping).
* Additionally, you should create the three columns `id`, `dateCreated` and
* `dateModified`. Lisk will automatically manage these, using them to implement
* autoincrement IDs and timestamps. If you do not want to use these features,
* see @{method:getConfiguration} for information on disabling them. At a bare
* minimum, you must normally have an `id` column which is a primary or unique
* key with a numeric type, although you can change its name by overriding
* @{method:getIDKey} or disable it entirely by overriding @{method:getIDKey} to
* return null. Note that many methods rely on a single-part primary key and
* will no longer work (they will throw) if you disable it.
*
* As you add more properties to your class in the future, remember to add them
* to the database table as well.
*
* Lisk will now automatically handle these operations: getting and setting
* properties, saving objects, loading individual objects, loading groups
* of objects, updating objects, managing IDs, updating timestamps whenever
* an object is created or modified, and some additional specialized
* operations.
*
* = Creating, Retrieving, Updating, and Deleting =
*
* To create and persist a Lisk object, use @{method:save}:
*
* $dog = id(new Dog())
* ->setName('Sawyer')
* ->setBreed('Pug')
* ->save();
*
* Note that **Lisk automatically builds getters and setters for all of your
* object's protected properties** via @{method:__call}. If you want to add
* custom behavior to your getters or setters, you can do so by overriding the
* @{method:readField} and @{method:writeField} methods.
*
* Calling @{method:save} will persist the object to the database. After calling
* @{method:save}, you can call @{method:getID} to retrieve the object's ID.
*
* To load objects by ID, use the @{method:load} method:
*
* $dog = id(new Dog())->load($id);
*
* This will load the Dog record with ID $id into $dog, or ##null## if no such
* record exists (@{method:load} is an instance method rather than a static
* method because PHP does not support late static binding, at least until PHP
* 5.3).
*
* To update an object, change its properties and save it:
*
* $dog->setBreed('Lab')->save();
*
* To delete an object, call @{method:delete}:
*
* $dog->delete();
*
* That's Lisk CRUD in a nutshell.
*
* = Queries =
*
* Often, you want to load a bunch of objects, or execute a more specialized
* query. Use @{method:loadAllWhere} or @{method:loadOneWhere} to do this:
*
* $pugs = $dog->loadAllWhere('breed = %s', 'Pug');
* $sawyer = $dog->loadOneWhere('name = %s', 'Sawyer');
*
* These methods work like @{function:queryfx}, but only take half of a query
* (the part after the WHERE keyword). Lisk will handle the connection, columns,
* and object construction; you are responsible for the rest of it.
* @{method:loadAllWhere} returns a list of objects, while
* @{method:loadOneWhere} returns a single object (or `null`).
*
* There's also a @{method:loadRelatives} method which helps to prevent the 1+N
* queries problem.
*
* = Managing Transactions =
*
* Lisk uses a transaction stack, so code does not generally need to be aware
* of the transactional state of objects to implement correct transaction
* semantics:
*
* $obj->openTransaction();
* $obj->save();
* $other->save();
* // ...
* $other->openTransaction();
* $other->save();
* $another->save();
* if ($some_condition) {
* $other->saveTransaction();
* } else {
* $other->killTransaction();
* }
* // ...
* $obj->saveTransaction();
*
* Assuming ##$obj##, ##$other## and ##$another## live on the same database,
* this code will work correctly by establishing savepoints.
*
* Selects whose data are used later in the transaction should be included in
* @{method:beginReadLocking} or @{method:beginWriteLocking} block.
*
* @task conn Managing Connections
* @task config Configuring Lisk
* @task load Loading Objects
* @task info Examining Objects
* @task save Writing Objects
* @task hook Hooks and Callbacks
* @task util Utilities
* @task xaction Managing Transactions
* @task isolate Isolation for Unit Testing
*
* @group storage
*/
abstract class LiskDAO {
const CONFIG_OPTIMISTIC_LOCKS = 'enable-locks';
const CONFIG_IDS = 'id-mechanism';
const CONFIG_TIMESTAMPS = 'timestamps';
const CONFIG_AUX_PHID = 'auxiliary-phid';
const CONFIG_SERIALIZATION = 'col-serialization';
const CONFIG_PARTIAL_OBJECTS = 'partial-objects';
const SERIALIZATION_NONE = 'id';
const SERIALIZATION_JSON = 'json';
const SERIALIZATION_PHP = 'php';
const IDS_AUTOINCREMENT = 'ids-auto';
const IDS_PHID = 'ids-phid';
const IDS_MANUAL = 'ids-manual';
private $__dirtyFields = array();
private $__missingFields = array();
private static $processIsolationLevel = 0;
private static $transactionIsolationLevel = 0;
private static $__checkedClasses = array();
private $__ephemeral = false;
private static $connections = array();
private $inSet = null;
/**
* Build an empty object.
*
* @return obj Empty object.
*/
public function __construct() {
$id_key = $this->getIDKey();
if ($id_key) {
$this->$id_key = null;
}
if ($this->getConfigOption(self::CONFIG_PARTIAL_OBJECTS)) {
$this->resetDirtyFields();
$this_class = get_class($this);
if (empty(self::$__checkedClasses[$this_class])) {
self::$__checkedClasses = true;
if (PhabricatorEnv::getEnvConfig('lisk.check_property_methods')) {
$class = new ReflectionClass(get_class($this));
$methods = $class->getMethods();
$properties = $this->getProperties();
foreach ($methods as $method) {
$name = strtolower($method->getName());
if (!(strncmp($name, 'get', 3) && strncmp($name, 'set', 3))) {
$name = substr($name, 3);
$declaring_class_name = $method->getDeclaringClass()->getName();
if (isset($properties[$name]) &&
$declaring_class_name !== 'LiskDAO') {
throw new Exception(
"Cannot implement method {$method->getName()} in ".
"{$declaring_class_name}.");
}
}
}
}
}
}
}
/* -( Managing Connections )----------------------------------------------- */
/**
* Establish a live connection to a database service. This method should
* return a new connection. Lisk handles connection caching and management;
* do not perform caching deeper in the stack.
*
* @param string Mode, either 'r' (reading) or 'w' (reading and writing).
* @return AphrontDatabaseConnection New database connection.
* @task conn
*/
abstract protected function establishLiveConnection($mode);
/**
* Return a namespace for this object's connections in the connection cache.
* Generally, the database name is appropriate. Two connections are considered
* equivalent if they have the same connection namespace and mode.
*
* @return string Connection namespace for cache
* @task conn
*/
abstract protected function getConnectionNamespace();
/**
* Get an existing, cached connection for this object.
*
* @param mode Connection mode.
* @return AprontDatabaseConnection|null Connection, if it exists in cache.
* @task conn
*/
protected function getEstablishedConnection($mode) {
$key = $this->getConnectionNamespace().':'.$mode;
if (isset(self::$connections[$key])) {
return self::$connections[$key];
}
return null;
}
/**
* Store a connection in the connection cache.
*
* @param mode Connection mode.
* @param AphrontDatabaseConnection Connection to cache.
* @return this
* @task conn
*/
protected function setEstablishedConnection(
$mode,
AphrontDatabaseConnection $connection) {
$key = $this->getConnectionNamespace().':'.$mode;
self::$connections[$key] = $connection;
return $this;
}
/* -( Configuring Lisk )--------------------------------------------------- */
/**
* Change Lisk behaviors, like optimistic locks and timestamps. If you want
* to change these behaviors, you should override this method in your child
* class and change the options you're interested in. For example:
*
* public function getConfiguration() {
* return array(
* Lisk_DataAccessObject::CONFIG_EXAMPLE => true,
* ) + parent::getConfiguration();
* }
*
* The available options are:
*
* CONFIG_OPTIMISTIC_LOCKS
* Lisk automatically performs optimistic locking on objects, which protects
* you from read-modify-write concurrency problems. Lock failures are
* detected at write time and arise when two users read an object, then both
* save it. In theory, you should detect these failures and accommodate them
* in some sensible way (for instance, by showing the user differences
* between the original record and the copy they are trying to update, and
* prompting them to merge them). In practice, most Lisk tools are quick
* and dirty and don't get to that level of sophistication, but optimistic
* locks can still protect you from yourself sometimes. If you don't want
* to use optimistic locks, you can disable them. The performance cost of
* doing this locking is very very small (optimistic locks were chosen
* because they're simple and cheap, and highly optimized for the case where
* collisions are rare). By default, this option is OFF.
*
* CONFIG_IDS
* Lisk objects need to have a unique identifying ID. The three mechanisms
* available for generating this ID are IDS_AUTOINCREMENT (default, assumes
* the ID column is an autoincrement primary key), IDS_PHID (to generate a
* unique PHID for each object) or IDS_MANUAL (you are taking full
* responsibility for ID management).
*
* CONFIG_TIMESTAMPS
* Lisk can automatically handle keeping track of a `dateCreated' and
* `dateModified' column, which it will update when it creates or modifies
* an object. If you don't want to do this, you may disable this option.
* By default, this option is ON.
*
* CONFIG_AUX_PHID
* This option can be enabled by being set to some truthy value. The meaning
* of this value is defined by your PHID generation mechanism. If this option
* is enabled, a `phid' property will be populated with a unique PHID when an
* object is created (or if it is saved and does not currently have one). You
* need to override generatePHID() and hook it into your PHID generation
* mechanism for this to work. By default, this option is OFF.
*
* CONFIG_SERIALIZATION
* You can optionally provide a column serialization map that will be applied
* to values when they are written to the database. For example:
*
* self::CONFIG_SERIALIZATION => array(
* 'complex' => self::SERIALIZATION_JSON,
* )
*
* This will cause Lisk to JSON-serialize the 'complex' field before it is
* written, and unserialize it when it is read.
*
* CONFIG_PARTIAL_OBJECTS
* Sometimes, it is useful to load only some fields of an object (such as
* when you are loading all objects of a class, but only care about a few
* fields). Turning on this option (by setting it to a truthy value) allows
* users of the class to create/use partial objects, but it comes with some
* side effects: your class cannot override the setters and getters provided
* by Lisk (use readField and writeField instead), and you should not
* directly access or assign protected members of your class (use the getters
* and setters).
*
*
* @return dictionary Map of configuration options to values.
*
* @task config
*/
protected function getConfiguration() {
return array(
self::CONFIG_OPTIMISTIC_LOCKS => false,
self::CONFIG_IDS => self::IDS_AUTOINCREMENT,
self::CONFIG_TIMESTAMPS => true,
self::CONFIG_PARTIAL_OBJECTS => false,
);
}
/**
* Determine the setting of a configuration option for this class of objects.
*
* @param const Option name, one of the CONFIG_* constants.
* @return mixed Option value, if configured (null if unavailable).
*
* @task config
*/
public function getConfigOption($option_name) {
static $options = null;
if (!isset($options)) {
$options = $this->getConfiguration();
}
return idx($options, $option_name);
}
/* -( Loading Objects )---------------------------------------------------- */
/**
* Load an object by ID. You need to invoke this as an instance method, not
* a class method, because PHP doesn't have late static binding (until
* PHP 5.3.0). For example:
*
* $dog = id(new Dog())->load($dog_id);
*
* @param int Numeric ID identifying the object to load.
* @return obj|null Identified object, or null if it does not exist.
*
* @task load
*/
public function load($id) {
if (!($id = (int)$id)) {
throw new Exception("Bogus ID provided to load().");
}
return $this->loadOneWhere(
'%C = %d',
$this->getIDKeyForUse(),
$id);
}
/**
* Loads all of the objects, unconditionally.
*
* @return dict Dictionary of all persisted objects of this type, keyed
* on object ID.
*
* @task load
*/
public function loadAll() {
return $this->loadAllWhere('1 = 1');
}
/**
* Loads all objects, but only fetches the specified columns.
*
* @param array Array of canonical column names as strings
* @return dict Dictionary of all objects, keyed by ID.
*
* @task load
*/
public function loadColumns(array $columns) {
return $this->loadColumnsWhere($columns, '1 = 1');
}
/**
* Load all objects which match a WHERE clause. You provide everything after
* the 'WHERE'; Lisk handles everything up to it. For example:
*
* $old_dogs = id(new Dog())->loadAllWhere('age > %d', 7);
*
* The pattern and arguments are as per queryfx().
*
* @param string queryfx()-style SQL WHERE clause.
* @param ... Zero or more conversions.
* @return dict Dictionary of matching objects, keyed on ID.
*
* @task load
*/
public function loadAllWhere($pattern/*, $arg, $arg, $arg ... */) {
$args = func_get_args();
array_unshift($args, null);
$data = call_user_func_array(
array($this, 'loadRawDataWhere'),
$args);
return $this->loadAllFromArray($data);
}
/**
* Loads selected columns from objects that match a WHERE clause. You must
* provide everything after the WHERE. See loadAllWhere().
*
* @param array List of column names.
* @param string queryfx()-style SQL WHERE clause.
* @param ... Zero or more conversions.
* @return dict Dictionary of matching objecks, keyed by ID.
*
* @task load
*/
public function loadColumnsWhere(array $columns, $pattern/*, $args... */) {
if (!$this->getConfigOption(self::CONFIG_PARTIAL_OBJECTS)) {
throw new BadMethodCallException(
"This class does not support partial objects.");
}
$args = func_get_args();
$data = call_user_func_array(
array($this, 'loadRawDataWhere'),
$args);
return $this->loadAllFromArray($data);
}
/**
* Load a single object identified by a 'WHERE' clause. You provide
* everything after the 'WHERE', and Lisk builds the first half of the
* query. See loadAllWhere(). This method is similar, but returns a single
* result instead of a list.
*
* @param string queryfx()-style SQL WHERE clause.
* @param ... Zero or more conversions.
* @return obj|null Matching object, or null if no object matches.
*
* @task load
*/
public function loadOneWhere($pattern/*, $arg, $arg, $arg ... */) {
$args = func_get_args();
array_unshift($args, null);
$data = call_user_func_array(
array($this, 'loadRawDataWhere'),
$args);
if (count($data) > 1) {
throw new AphrontQueryCountException(
"More than 1 result from loadOneWhere()!");
}
$data = reset($data);
if (!$data) {
return null;
}
return $this->loadFromArray($data);
}
protected function loadRawDataWhere($columns, $pattern/*, $args... */) {
$connection = $this->establishConnection('r');
$lock_clause = '';
if ($connection->isReadLocking()) {
$lock_clause = 'FOR UPDATE';
} else if ($connection->isWriteLocking()) {
$lock_clause = 'LOCK IN SHARE MODE';
}
$args = func_get_args();
$args = array_slice($args, 2);
if (!$columns) {
$column = '*';
} else {
$column = '%LC';
$columns[] = $this->getIDKey();
$properties = $this->getProperties();
$this->__missingFields = array_diff_key(
array_flip($properties),
array_flip($columns));
}
$pattern = 'SELECT '.$column.' FROM %T WHERE '.$pattern.' %Q';
array_unshift($args, $this->getTableName());
if ($columns) {
array_unshift($args, $columns);
}
array_push($args, $lock_clause);
array_unshift($args, $pattern);
return call_user_func_array(
array($connection, 'queryData'),
$args);
}
/**
* Reload an object from the database, discarding any changes to persistent
* properties. If the object uses optimistic locks and you are in a locking
* mode while transactional, this will effectively synchronize the locks.
* This is pretty heady. It is unlikely you need to use this method.
*
* @return this
*
* @task load
*/
public function reload() {
if (!$this->getID()) {
throw new Exception("Unable to reload object that hasn't been loaded!");
}
$use_locks = $this->getConfigOption(self::CONFIG_OPTIMISTIC_LOCKS);
if (!$use_locks) {
$result = $this->loadOneWhere(
'%C = %d',
$this->getIDKeyForUse(),
$this->getID());
} else {
$result = $this->loadOneWhere(
'%C = %d AND %C = %d',
$this->getIDKeyForUse(),
$this->getID(),
'version',
$this->getVersion());
}
if (!$result) {
throw new AphrontQueryObjectMissingException($use_locks);
}
return $this;
}
/**
* Initialize this object's properties from a dictionary. Generally, you
* load single objects with loadOneWhere(), but sometimes it may be more
* convenient to pull data from elsewhere directly (e.g., a complicated
* join via queryData()) and then load from an array representation.
*
* @param dict Dictionary of properties, which should be equivalent to
* selecting a row from the table or calling getProperties().
* @return this
*
* @task load
*/
public function loadFromArray(array $row) {
// TODO: We should load only valid properties.
$map = array();
foreach ($row as $k => $v) {
$map[$k] = $v;
}
$this->willReadData($map);
foreach ($map as $prop => $value) {
$this->$prop = $value;
}
$this->didReadData();
return $this;
}
/**
* Initialize a list of objects from a list of dictionaries. Usually you
* load lists of objects with loadAllWhere(), but sometimes that isn't
* flexible enough. One case is if you need to do joins to select the right
* objects:
*
* function loadAllWithOwner($owner) {
* $data = $this->queryData(
* 'SELECT d.*
* FROM owner o
* JOIN owner_has_dog od ON o.id = od.ownerID
* JOIN dog d ON od.dogID = d.id
* WHERE o.id = %d',
* $owner);
* return $this->loadAllFromArray($data);
* }
*
* This is a lot messier than loadAllWhere(), but more flexible.
*
* @param list List of property dictionaries.
* @return dict List of constructed objects, keyed on ID.
*
* @task load
*/
public function loadAllFromArray(array $rows) {
$result = array();
$id_key = $this->getIDKey();
foreach ($rows as $row) {
$obj = clone $this;
if ($id_key && isset($row[$id_key])) {
$result[$row[$id_key]] = $obj->loadFromArray($row);
} else {
$result[] = $obj->loadFromArray($row);
}
if ($this->inSet) {
$this->inSet->addToSet($obj);
}
}
return $result;
}
/**
* This method helps to prevent the 1+N queries problem. It happens when you
* execute a query for each row in a result set. Like in this code:
*
* COUNTEREXAMPLE, name=Easy to write but expensive to execute
* $diffs = id(new DifferentialDiff())->loadAllWhere(
* 'revisionID = %d',
* $revision->getID());
* foreach ($diffs as $diff) {
* $changesets = id(new DifferentialChangeset())->loadAllWhere(
* 'diffID = %d',
* $diff->getID());
* // Do something with $changesets.
* }
*
* One can solve this problem by reading all the dependent objects at once and
* assigning them later:
*
* COUNTEREXAMPLE, name=Cheaper to execute but harder to write and maintain
* $diffs = id(new DifferentialDiff())->loadAllWhere(
* 'revisionID = %d',
* $revision->getID());
* $all_changesets = id(new DifferentialChangeset())->loadAllWhere(
* 'diffID IN (%Ld)',
* mpull($diffs, 'getID'));
* $all_changesets = mgroup($all_changesets, 'getDiffID');
* foreach ($diffs as $diff) {
* $changesets = idx($all_changesets, $diff->getID(), array());
* // Do something with $changesets.
* }
*
* The method @{method:loadRelatives} abstracts this approach which allows
* writing a code which is simple and efficient at the same time:
*
* name=Easy to write and cheap to execute
* $diffs = $revision->loadRelatives(new DifferentialDiff(), 'revisionID');
* foreach ($diffs as $diff) {
* $changesets = $diff->loadRelatives(
* new DifferentialChangeset(),
* 'diffID');
* // Do something with $changesets.
* }
*
* This will load dependent objects for all diffs in the first call of
* @{method:loadRelatives} and use this result for all following calls.
*
* The method supports working with set of sets, like in this code:
*
* $diffs = $revision->loadRelatives(new DifferentialDiff(), 'revisionID');
* foreach ($diffs as $diff) {
* $changesets = $diff->loadRelatives(
* new DifferentialChangeset(),
* 'diffID');
* foreach ($changesets as $changeset) {
* $hunks = $changeset->loadRelatives(
* new DifferentialHunk(),
* 'changesetID');
* // Do something with hunks.
* }
* }
*
* This code will execute just three queries - one to load all diffs, one to
* load all their related changesets and one to load all their related hunks.
* You can try to write an equivalent code without using this method as
* a homework.
*
* The method also supports retrieving referenced objects, for example authors
* of all diffs (using shortcut @{method:loadOneRelative}):
*
* foreach ($diffs as $diff) {
* $author = $diff->loadOneRelative(
* new PhabricatorUser(),
* 'phid',
* 'getAuthorPHID');
* // Do something with author.
* }
*
* It is also possible to specify additional conditions for the `WHERE`
* clause. Similarly to @{method:loadAllWhere}, you can specify everything
* after `WHERE` (except `LIMIT`). Contrary to @{method:loadAllWhere}, it is
* allowed to pass only a constant string (`%` doesn't have a special
* meaning). This is intentional to avoid mistakes with using data from one
* row in retrieving other rows. Example of a correct usage:
*
* $status = $author->loadOneRelative(
* new PhabricatorUserStatus(),
* 'userPHID',
* 'getPHID',
* '(UNIX_TIMESTAMP() BETWEEN dateFrom AND dateTo)');
*
* @param LiskDAO Type of objects to load.
* @param string Name of the column in target table.
* @param string Method name in this table.
* @param string Additional constraints on returned rows. It supports no
* placeholders and requires putting the WHERE part into
* parentheses. It's not possible to use LIMIT.
* @return list Objects of type $object.
*
* @task load
*/
public function loadRelatives(
LiskDAO $object,
$foreign_column,
$key_method = 'getID',
$where = '') {
if (!$this->inSet) {
id(new LiskDAOSet())->addToSet($this);
}
$relatives = $this->inSet->loadRelatives(
$object,
$foreign_column,
$key_method,
$where);
return idx($relatives, $this->$key_method(), array());
}
/**
* Load referenced row. See @{method:loadRelatives} for details.
*
* @param LiskDAO Type of objects to load.
* @param string Name of the column in target table.
* @param string Method name in this table.
* @param string Additional constraints on returned rows. It supports no
* placeholders and requires putting the WHERE part into
* parentheses. It's not possible to use LIMIT.
* @return LiskDAO Object of type $object or null if there's no such object.
*
* @task load
*/
final public function loadOneRelative(
LiskDAO $object,
$foreign_column,
$key_method = 'getID',
$where = '') {
$relatives = $this->loadRelatives(
$object,
$foreign_column,
$key_method,
$where);
if (!$relatives) {
return null;
}
if (count($relatives) > 1) {
throw new AphrontQueryCountException(
"More than 1 result from loadOneRelative()!");
}
return reset($relatives);
}
final public function putInSet(LiskDAOSet $set) {
$this->inSet = $set;
return $this;
}
/* -( Examining Objects )-------------------------------------------------- */
/**
* Retrieve the unique, numerical ID identifying this object. This value
* will be null if the object hasn't been persisted.
*
* @return int Unique numerical ID.
*
* @task info
*/
public function getID() {
static $id_key = null;
if ($id_key === null) {
$id_key = $this->getIDKeyForUse();
}
return $this->$id_key;
}
/**
* Retrieve a list of all object properties. This list only includes
* properties that are declared as protected, and it is expected that
* all properties returned by this function should be persisted to the
* database.
* Properties that should not be persisted must be declared as private.
*
* @return dict Dictionary of normalized (lowercase) to canonical (original
* case) property names.
*
* @task info
*/
protected function getProperties() {
static $properties = null;
if (!isset($properties)) {
$class = new ReflectionClass(get_class($this));
$properties = array();
foreach ($class->getProperties(ReflectionProperty::IS_PROTECTED) as $p) {
$properties[strtolower($p->getName())] = $p->getName();
}
$id_key = $this->getIDKey();
if ($id_key) {
if (!isset($properties[strtolower($id_key)])) {
$properties[strtolower($id_key)] = $id_key;
}
}
if ($this->getConfigOption(self::CONFIG_OPTIMISTIC_LOCKS)) {
$properties['version'] = 'version';
}
if ($this->getConfigOption(self::CONFIG_TIMESTAMPS)) {
$properties['datecreated'] = 'dateCreated';
$properties['datemodified'] = 'dateModified';
}
if (!$this->isPHIDPrimaryID() &&
$this->getConfigOption(self::CONFIG_AUX_PHID)) {
$properties['phid'] = 'phid';
}
}
return $properties;
}
/**
* Check if a property exists on this object.
*
* @return string|null Canonical property name, or null if the property
* does not exist.
*
* @task info
*/
protected function checkProperty($property) {
static $properties = null;
if ($properties === null) {
$properties = $this->getProperties();
}
$property = strtolower($property);
if (empty($properties[$property])) {
return null;
}
return $properties[$property];
}
/**
* Get or build the database connection for this object.
*
* @param string 'r' for read, 'w' for read/write.
* @param bool True to force a new connection. The connection will not
* be retrieved from or saved into the connection cache.
* @return LiskDatabaseConnection Lisk connection object.
*
* @task info
*/
public function establishConnection($mode, $force_new = false) {
if ($mode != 'r' && $mode != 'w') {
throw new Exception("Unknown mode '{$mode}', should be 'r' or 'w'.");
}
if (self::shouldIsolateAllLiskEffectsToCurrentProcess()) {
$mode = 'isolate-'.$mode;
$connection = $this->getEstablishedConnection($mode);
if (!$connection) {
$connection = $this->establishIsolatedConnection($mode);
$this->setEstablishedConnection($mode, $connection);
}
return $connection;
}
if (self::shouldIsolateAllLiskEffectsToTransactions()) {
// If we're doing fixture transaction isolation, force the mode to 'w'
// so we always get the same connection for reads and writes, and thus
// can see the writes inside the transaction.
$mode = 'w';
}
// TODO: There is currently no protection on 'r' queries against writing.
$connection = null;
if (!$force_new) {
if ($mode == 'r') {
// If we're requesting a read connection but already have a write
// connection, reuse the write connection so that reads can take place
// inside transactions.
$connection = $this->getEstablishedConnection('w');
}
if (!$connection) {
$connection = $this->getEstablishedConnection($mode);
}
}
if (!$connection) {
$connection = $this->establishLiveConnection($mode);
if (self::shouldIsolateAllLiskEffectsToTransactions()) {
$connection->openTransaction();
}
if (!$force_new) {
$this->setEstablishedConnection($mode, $connection);
}
}
return $connection;
}
/**
* Convert this object into a property dictionary. This dictionary can be
* restored into an object by using loadFromArray() (unless you're using
* legacy features with CONFIG_CONVERT_CAMELCASE, but in that case you should
* just go ahead and die in a fire).
*
* @return dict Dictionary of object properties.
*
* @task info
*/
protected function getPropertyValues() {
$map = array();
foreach ($this->getProperties() as $p) {
// We may receive a warning here for properties we've implicitly added
// through configuration; squelch it.
$map[$p] = @$this->$p;
}
return $map;
}
/* -( Writing Objects )---------------------------------------------------- */
/**
* Make an object read-only.
*
* Making an object ephemeral indicates that you will be changing state in
* such a way that you would never ever want it to be written back to the
* storage.
*/
public function makeEphemeral() {
$this->__ephemeral = true;
return $this;
}
private function isEphemeralCheck() {
if ($this->__ephemeral) {
throw new LiskEphemeralObjectException();
}
}
/**
* Persist this object to the database. In most cases, this is the only
* method you need to call to do writes. If the object has not yet been
* inserted this will do an insert; if it has, it will do an update.
*
* @return this
*
* @task save
*/
public function save() {
if ($this->shouldInsertWhenSaved()) {
return $this->insert();
} else {
return $this->update();
}
}
/**
* Save this object, forcing the query to use REPLACE regardless of object
* state.
*
* @return this
*
* @task save
*/
public function replace() {
$this->isEphemeralCheck();
return $this->insertRecordIntoDatabase('REPLACE');
}
/**
* Save this object, forcing the query to use INSERT regardless of object
* state.
*
* @return this
*
* @task save
*/
public function insert() {
$this->isEphemeralCheck();
return $this->insertRecordIntoDatabase('INSERT');
}
/**
* Save this object, forcing the query to use UPDATE regardless of object
* state.
*
* @return this
*
* @task save
*/
public function update() {
$this->isEphemeralCheck();
$use_locks = $this->getConfigOption(self::CONFIG_OPTIMISTIC_LOCKS);
$this->willSaveObject();
$data = $this->getPropertyValues();
if ($this->getConfigOption(self::CONFIG_PARTIAL_OBJECTS)) {
$data = array_intersect_key($data, $this->__dirtyFields);
}
$this->willWriteData($data);
$map = array();
foreach ($data as $k => $v) {
if ($use_locks && $k == 'version') {
continue;
}
$map[$k] = $v;
}
$conn = $this->establishConnection('w');
foreach ($map as $key => $value) {
$map[$key] = qsprintf($conn, '%C = %ns', $key, $value);
}
$map = implode(', ', $map);
if ($use_locks) {
$conn->query(
'UPDATE %T SET %Q, version = version + 1 WHERE %C = %d AND %C = %d',
$this->getTableName(),
$map,
$this->getIDKeyForUse(),
$this->getID(),
'version',
$this->getVersion());
if ($conn->getAffectedRows() !== 1) {
throw new AphrontQueryObjectMissingException($use_locks);
}
$this->setVersion($this->getVersion() + 1);
} else {
$id = $this->getID();
$conn->query(
'UPDATE %T SET %Q WHERE %C = '.(is_int($id) ? '%d' : '%s'),
$this->getTableName(),
$map,
$this->getIDKeyForUse(),
$id);
// We can't detect a missing object because updating an object without
// changing any values doesn't affect rows. We could jiggle timestamps
// to catch this for objects which track them if we wanted.
}
$this->didWriteData();
if ($this->getConfigOption(self::CONFIG_PARTIAL_OBJECTS)) {
$this->resetDirtyFields();
}
return $this;
}
/**
* Delete this object, permanently.
*
* @return this
*
* @task save
*/
public function delete() {
$this->isEphemeralCheck();
$this->willDelete();
$conn = $this->establishConnection('w');
$conn->query(
'DELETE FROM %T WHERE %C = %d',
$this->getTableName(),
$this->getIDKeyForUse(),
$this->getID());
$this->didDelete();
return $this;
}
/**
* Internal implementation of INSERT and REPLACE.
*
* @param const Either "INSERT" or "REPLACE", to force the desired mode.
*
* @task save
*/
protected function insertRecordIntoDatabase($mode) {
$this->willSaveObject();
$data = $this->getPropertyValues();
$id_mechanism = $this->getConfigOption(self::CONFIG_IDS);
switch ($id_mechanism) {
case self::IDS_AUTOINCREMENT:
// If we are using autoincrement IDs, let MySQL assign the value for the
// ID column, if it is empty. If the caller has explicitly provided a
// value, use it.
$id_key = $this->getIDKeyForUse();
if (empty($data[$id_key])) {
unset($data[$id_key]);
}
break;
case self::IDS_PHID:
if (empty($data[$this->getIDKeyForUse()])) {
$phid = $this->generatePHID();
$this->setID($phid);
$data[$this->getIDKeyForUse()] = $phid;
}
break;
case self::IDS_MANUAL:
break;
default:
throw new Exception('Unknown CONFIG_IDs mechanism!');
}
if ($this->getConfigOption(self::CONFIG_OPTIMISTIC_LOCKS)) {
$data['version'] = 0;
}
$this->willWriteData($data);
$conn = $this->establishConnection('w');
$columns = array_keys($data);
foreach ($data as $key => $value) {
$data[$key] = qsprintf($conn, '%ns', $value);
}
$data = implode(', ', $data);
$conn->query(
'%Q INTO %T (%LC) VALUES (%Q)',
$mode,
$this->getTableName(),
$columns,
$data);
// Update the object with the initial Version value
if ($this->getConfigOption(self::CONFIG_OPTIMISTIC_LOCKS)) {
$this->setVersion(0);
}
// Only use the insert id if this table is using auto-increment ids
if ($id_mechanism === self::IDS_AUTOINCREMENT) {
$this->setID($conn->getInsertID());
}
$this->didWriteData();
if ($this->getConfigOption(self::CONFIG_PARTIAL_OBJECTS)) {
$this->resetDirtyFields();
}
return $this;
}
/**
* Method used to determine whether to insert or update when saving.
*
* @return bool true if the record should be inserted
*/
protected function shouldInsertWhenSaved() {
$key_type = $this->getConfigOption(self::CONFIG_IDS);
$use_locks = $this->getConfigOption(self::CONFIG_OPTIMISTIC_LOCKS);
if ($key_type == self::IDS_MANUAL) {
if ($use_locks) {
// If we are manually keyed and the object has a version (which means
// that it has been saved to the DB before), do an update, otherwise
// perform an insert.
if ($this->getID() && $this->getVersion() !== null) {
return false;
} else {
return true;
}
} else {
throw new Exception(
'You are not using optimistic locks, but are using manual IDs. You '.
'must override the shouldInsertWhenSaved() method to properly '.
'detect when to insert a new record.');
}
} else {
return !$this->getID();
}
}
/* -( Hooks and Callbacks )------------------------------------------------ */
/**
* Retrieve the database table name. By default, this is the class name.
*
* @return string Table name for object storage.
*
* @task hook
*/
public function getTableName() {
return get_class($this);
}
/**
* Helper: Whether this class is configured to use PHIDs as the primary ID.
* @task internal
*/
private function isPHIDPrimaryID() {
return ($this->getConfigOption(self::CONFIG_IDS) === self::IDS_PHID);
}
/**
* Retrieve the primary key column, "id" by default. If you can not
* reasonably name your ID column "id", override this method.
*
* @return string Name of the ID column.
*
* @task hook
*/
public function getIDKey() {
return
$this->isPHIDPrimaryID() ?
'phid' :
'id';
}
protected function getIDKeyForUse() {
$id_key = $this->getIDKey();
if (!$id_key) {
throw new Exception(
"This DAO does not have a single-part primary key. The method you ".
"called requires a single-part primary key.");
}
return $id_key;
}
/**
* Generate a new PHID, used by CONFIG_AUX_PHID and IDS_PHID.
*
* @return phid Unique, newly allocated PHID.
*
* @task hook
*/
protected function generatePHID() {
throw new Exception(
"To use CONFIG_AUX_PHID or IDS_PHID, you need to overload ".
"generatePHID() to perform PHID generation.");
}
/**
* Hook to apply serialization or validation to data before it is written to
* the database. See also willReadData().
*
* @task hook
*/
protected function willWriteData(array &$data) {
$this->applyLiskDataSerialization($data, false);
}
/**
* Hook to perform actions after data has been written to the database.
*
* @task hook
*/
protected function didWriteData() {}
/**
* Hook to make internal object state changes prior to INSERT, REPLACE or
* UPDATE.
*
* @task hook
*/
protected function willSaveObject() {
$use_timestamps = $this->getConfigOption(self::CONFIG_TIMESTAMPS);
if ($use_timestamps) {
if (!$this->getDateCreated()) {
$this->setDateCreated(time());
}
$this->setDateModified(time());
}
if (($this->isPHIDPrimaryID() && !$this->getID())) {
// If PHIDs are the primary ID, the subclass could have overridden the
// name of the ID column.
$this->setID($this->generatePHID());
} else if ($this->getConfigOption(self::CONFIG_AUX_PHID) &&
!$this->getPHID()) {
// The subclass could still want PHIDs.
$this->setPHID($this->generatePHID());
}
}
/**
* Hook to apply serialization or validation to data as it is read from the
* database. See also willWriteData().
*
* @task hook
*/
protected function willReadData(array &$data) {
$this->applyLiskDataSerialization($data, $deserialize = true);
}
/**
* Hook to perform an action on data after it is read from the database.
*
* @task hook
*/
protected function didReadData() {}
/**
* Hook to perform an action before the deletion of an object.
*
* @task hook
*/
protected function willDelete() {}
/**
* Hook to perform an action after the deletion of an object.
*
* @task hook
*/
protected function didDelete() {}
/**
* Reads the value from a field. Override this method for custom behavior
* of getField() instead of overriding getField directly.
*
* @param string Canonical field name
* @return mixed Value of the field
*
* @task hook
*/
protected function readField($field) {
if (isset($this->$field)) {
return $this->$field;
}
return null;
}
/**
* Writes a value to a field. Override this method for custom behavior of
* setField($value) instead of overriding setField directly.
*
* @param string Canonical field name
* @param mixed Value to write
*
* @task hook
*/
protected function writeField($field, $value) {
$this->$field = $value;
}
/* -( Manging Transactions )----------------------------------------------- */
/**
* Increase transaction stack depth.
*
* @return this
*/
public function openTransaction() {
$this->establishConnection('w')->openTransaction();
return $this;
}
/**
* Decrease transaction stack depth, saving work.
*
* @return this
*/
public function saveTransaction() {
$this->establishConnection('w')->saveTransaction();
return $this;
}
/**
* Decrease transaction stack depth, discarding work.
*
* @return this
*/
public function killTransaction() {
$this->establishConnection('w')->killTransaction();
return $this;
}
/**
* Begins read-locking selected rows with SELECT ... FOR UPDATE, so that
* other connections can not read them (this is an enormous oversimplification
* of FOR UPDATE semantics; consult the MySQL documentation for details). To
* end read locking, call @{method:endReadLocking}. For example:
*
* $beach->openTransaction();
* $beach->beginReadLocking();
*
* $beach->reload();
* $beach->setGrainsOfSand($beach->getGrainsOfSand() + 1);
* $beach->save();
*
* $beach->endReadLocking();
* $beach->saveTransaction();
*
* @return this
* @task xaction
*/
public function beginReadLocking() {
$this->establishConnection('w')->beginReadLocking();
return $this;
}
/**
* Ends read-locking that began at an earlier @{method:beginReadLocking} call.
*
* @return this
* @task xaction
*/
public function endReadLocking() {
$this->establishConnection('w')->endReadLocking();
return $this;
}
/**
* Begins write-locking selected rows with SELECT ... LOCK IN SHARE MODE, so
* that other connections can not update or delete them (this is an
* oversimplification of LOCK IN SHARE MODE semantics; consult the
* MySQL documentation for details). To end write locking, call
* @{method:endWriteLocking}.
*
* @return this
* @task xaction
*/
public function beginWriteLocking() {
$this->establishConnection('w')->beginWriteLocking();
return $this;
}
/**
* Ends write-locking that began at an earlier @{method:beginWriteLocking}
* call.
*
* @return this
* @task xaction
*/
public function endWriteLocking() {
$this->establishConnection('w')->endWriteLocking();
return $this;
}
/* -( Isolation )---------------------------------------------------------- */
/**
* @task isolate
*/
public static function beginIsolateAllLiskEffectsToCurrentProcess() {
self::$processIsolationLevel++;
}
/**
* @task isolate
*/
public static function endIsolateAllLiskEffectsToCurrentProcess() {
self::$processIsolationLevel--;
if (self::$processIsolationLevel < 0) {
throw new Exception(
"Lisk process isolation level was reduced below 0.");
}
}
/**
* @task isolate
*/
public static function shouldIsolateAllLiskEffectsToCurrentProcess() {
return (bool)self::$processIsolationLevel;
}
/**
* @task isolate
*/
private function establishIsolatedConnection($mode) {
$config = array();
return new AphrontIsolatedDatabaseConnection($config);
}
/**
* @task isolate
*/
public static function beginIsolateAllLiskEffectsToTransactions() {
if (self::$transactionIsolationLevel === 0) {
self::closeAllConnections();
}
self::$transactionIsolationLevel++;
}
/**
* @task isolate
*/
public static function endIsolateAllLiskEffectsToTransactions() {
self::$transactionIsolationLevel--;
if (self::$transactionIsolationLevel < 0) {
throw new Exception(
"Lisk transaction isolation level was reduced below 0.");
} else if (self::$transactionIsolationLevel == 0) {
foreach (self::$connections as $key => $conn) {
if ($conn) {
$conn->killTransaction();
}
}
self::closeAllConnections();
}
}
/**
* @task isolate
*/
public static function shouldIsolateAllLiskEffectsToTransactions() {
return (bool)self::$transactionIsolationLevel;
}
public static function closeAllConnections() {
self::$connections = array();
}
/* -( Utilities )---------------------------------------------------------- */
/**
* Applies configured serialization to a dictionary of values.
*
* @task util
*/
protected function applyLiskDataSerialization(array &$data, $deserialize) {
$serialization = $this->getConfigOption(self::CONFIG_SERIALIZATION);
if ($serialization) {
foreach (array_intersect_key($serialization, $data) as $col => $format) {
switch ($format) {
case self::SERIALIZATION_NONE:
break;
case self::SERIALIZATION_PHP:
if ($deserialize) {
$data[$col] = unserialize($data[$col]);
} else {
$data[$col] = serialize($data[$col]);
}
break;
case self::SERIALIZATION_JSON:
if ($deserialize) {
$data[$col] = json_decode($data[$col], true);
} else {
$data[$col] = json_encode($data[$col]);
}
break;
default:
throw new Exception("Unknown serialization format '{$format}'.");
}
}
}
}
/**
* Resets the dirty fields (fields which need to be written on next save/
* update/insert/replace). If this DAO has timestamps, the modified time
* is always a dirty field.
*
* @task util
*/
private function resetDirtyFields() {
$this->__dirtyFields = array();
if ($this->getConfigOption(self::CONFIG_TIMESTAMPS)) {
$this->__dirtyFields['dateModified'] = true;
}
}
/**
* Black magic. Builds implied get*() and set*() for all properties.
*
* @param string Method name.
* @param list Argument vector.
* @return mixed get*() methods return the property value. set*() methods
* return $this.
* @task util
*/
public function __call($method, $args) {
// NOTE: This method is very performance-sensitive (many thousands of calls
// per page on some pages), and thus has some silliness in the name of
// optimizations.
static $dispatch_map = array();
static $partial = null;
if ($partial === null) {
$partial = $this->getConfigOption(self::CONFIG_PARTIAL_OBJECTS);
}
if ($method[0] === 'g') {
if (isset($dispatch_map[$method])) {
$property = $dispatch_map[$method];
} else {
if (substr($method, 0, 3) !== 'get') {
throw new Exception("Unable to resolve method '{$method}'!");
}
$property = substr($method, 3);
if (!($property = $this->checkProperty($property))) {
throw new Exception("Bad getter call: {$method}");
}
$dispatch_map[$method] = $property;
}
if ($partial && isset($this->__missingFields[$property])) {
throw new Exception("Cannot get field that wasn't loaded: {$property}");
}
return $this->readField($property);
}
if ($method[0] === 's') {
if (isset($dispatch_map[$method])) {
$property = $dispatch_map[$method];
} else {
if (substr($method, 0, 3) !== 'set') {
throw new Exception("Unable to resolve method '{$method}'!");
}
$property = substr($method, 3);
$property = $this->checkProperty($property);
if (!$property) {
throw new Exception("Bad setter call: {$method}");
}
if ($property == 'ID') {
$property = $this->getIDKeyForUse();
}
$dispatch_map[$method] = $property;
}
if ($partial) {
// Accept writes to fields that weren't initially loaded
unset($this->__missingFields[$property]);
$this->__dirtyFields[$property] = true;
}
$this->writeField($property, $args[0]);
return $this;
}
throw new Exception("Unable to resolve method '{$method}'.");
}
}
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