abstract class MigrationTask extends BuildTask (View source)

A migration task is a build task that is reversible.

Creating Migration Tasks

To create your own migration task, you need to define your own subclass of MigrationTask and implement the following methods

app/src/MyMigrationTask.php

class MyMigrationTask extends MigrationTask {

private static $segment = 'MyMigrationTask'; // segment in the dev/tasks/ namespace for URL access protected $title = "My Database Migrations"; // title of the script protected $description = "My Description"; // description of what it does

public function run($request) { if ($request->getVar('Direction') == 'down') { $this->down(); } else { $this->up(); } }

public function up() { // do something when going from old -> new }

public function down() { // do something when going from new -> old } }

Running Migration Tasks You can find all tasks under the dev/tasks/ namespace. To run the above script you would need to run the following and note - Either the site has to be in devmode or you need to add ?isDev=1 to the URL.

// url to visit if in dev mode. https://www.yoursite.com/dev/tasks/MyMigrationTask

// url to visit if you are in live mode but need to run this https://www.yoursite.com/dev/tasks/MyMigrationTask?isDev=1

Traits

A class that can be instantiated or replaced via DI

Provides extensions to this object to integrate it with standard config API methods.

Allows an object to have extensions applied to it.

Allows an object to declare a set of custom methods

Properties

static private array $extensions

An array of extension names and parameters to be applied to this object upon construction.

from  Extensible
static private string $segment

Set a custom url segment (to follow dev/tasks/)

from  BuildTask

Methods

static Injectable
create(array ...$args)

An implementation of the factory method, allows you to create an instance of a class

static Injectable
singleton(string $class = null)

Creates a class instance by the "singleton" design pattern.

static Config_ForClass
config()

Get a configuration accessor for this class. Short hand for Config::inst()->get($this->class, .....).

mixed
stat(string $name) deprecated

Get inherited config value

mixed
uninherited(string $name)

Gets the uninherited value for the given config option

$this
set_stat(string $name, mixed $value) deprecated

Update the config value for a given property

mixed
__call(string $method, array $arguments)

Attempts to locate and call a method dynamically added to a class at runtime if a default cannot be located

bool
hasMethod(string $method)

Return TRUE if a method exists on this object

array
allMethodNames(bool $custom = false)

Return the names of all the methods available on this object

static bool
add_extension(string $classOrExtension, string $extension = null)

Add an extension to a specific class.

static 
remove_extension(string $extension)

Remove an extension from a class.

static array
get_extensions(string $class = null, bool $includeArgumentString = false)

No description

static array|null
get_extra_config_sources(string $class = null)

Get extra config sources for this class

static bool
has_extension(string $classOrExtension, string $requiredExtension = null, bool $strict = false)

Return TRUE if a class has a specified extension.

array
invokeWithExtensions(string $method, mixed ...$arguments)

Calls a method if available on both this object and all applied {@link Extensions}, and then attempts to merge all results into an array

array
extend(string $method, mixed ...$arguments)

Run the given function on all of this object's extensions. Note that this method originally returned void, so if you wanted to return results, you're hosed

Extension|null
getExtensionInstance(string $extension)

Get an extension instance attached to this object by name.

bool
hasExtension(string $extension)

Returns TRUE if this object instance has a specific extension applied in {@link $extension_instances}. Extension instances are initialized at constructor time, meaning if you use {@link add_extension()} afterwards, the added extension will just be added to new instances of the extended class. Use the static method {@link has_extension()} to check if a class (not an instance) has a specific extension.

getExtensionInstances()

Get all extension instances for this specific object instance.

__construct()

No description

run(HTTPRequest $request)

Implement this method in the task subclass to execute via the TaskRunner

bool
isEnabled()

No description

string
getTitle()

No description

string
getDescription()

No description

up()

No description

down()

No description

Details

static Injectable create(array ...$args)

An implementation of the factory method, allows you to create an instance of a class

This method will defer class substitution to the Injector API, which can be customised via the Config API to declare substitution classes.

This can be called in one of two ways - either calling via the class directly, or calling on Object and passing the class name as the first parameter. The following are equivalent: $list = DataList::create('SiteTree'); $list = SiteTree::get();

Parameters

array ...$args

Return Value

Injectable

static Injectable singleton(string $class = null)

Creates a class instance by the "singleton" design pattern.

It will always return the same instance for this class, which can be used for performance reasons and as a simple way to access instance methods which don't rely on instance data (e.g. the custom SilverStripe static handling).

Parameters

string $class

Optional classname to create, if the called class should not be used

Return Value

Injectable

The singleton instance

static Config_ForClass config()

Get a configuration accessor for this class. Short hand for Config::inst()->get($this->class, .....).

Return Value

Config_ForClass

mixed stat(string $name) deprecated

deprecated 5.0 Use ->config()->get() instead

Get inherited config value

Parameters

string $name

Return Value

mixed

mixed uninherited(string $name)

Gets the uninherited value for the given config option

Parameters

string $name

Return Value

mixed

$this set_stat(string $name, mixed $value) deprecated

deprecated 5.0 Use ->config()->set() instead

Update the config value for a given property

Parameters

string $name
mixed $value

Return Value

$this

mixed __call(string $method, array $arguments)

Attempts to locate and call a method dynamically added to a class at runtime if a default cannot be located

You can add extra methods to a class using {@link Extensions}, {@link Object::createMethod()} or {@link Object::addWrapperMethod()}

Parameters

string $method
array $arguments

Return Value

mixed

Exceptions

BadMethodCallException

bool hasMethod(string $method)

Return TRUE if a method exists on this object

This should be used rather than PHP's inbuild method_exists() as it takes into account methods added via extensions

Parameters

string $method

Return Value

bool

array allMethodNames(bool $custom = false)

Return the names of all the methods available on this object

Parameters

bool $custom

include methods added dynamically at runtime

Return Value

array

Map of method names with lowercase keys

static bool add_extension(string $classOrExtension, string $extension = null)

Add an extension to a specific class.

The preferred method for adding extensions is through YAML config, since it avoids autoloading the class, and is easier to override in more specific configurations.

As an alternative, extensions can be added to a specific class directly in the {@link Object::$extensions} array. See {@link SiteTree::$extensions} for examples. Keep in mind that the extension will only be applied to new instances, not existing ones (including all instances created through {@link singleton()}).

Parameters

string $classOrExtension

Class that should be extended - has to be a subclass of {@link Object}

string $extension

Subclass of {@link Extension} with optional parameters as a string, e.g. "Versioned" or "Translatable('Param')"

Return Value

bool

Flag if the extension was added

See also

http://doc.silverstripe.org/framework/en/trunk/reference/dataextension

static remove_extension(string $extension)

Remove an extension from a class.

Note: This will not remove extensions from parent classes, and must be called directly on the class assigned the extension.

Keep in mind that this won't revert any datamodel additions of the extension at runtime, unless its used before the schema building kicks in (in your _config.php). Doesn't remove the extension from any {@link Object} instances which are already created, but will have an effect on new extensions. Clears any previously created singletons through {@link singleton()} to avoid side-effects from stale extension information.

Parameters

string $extension

class name of an {@link Extension} subclass, without parameters

static array get_extensions(string $class = null, bool $includeArgumentString = false)

Parameters

string $class

If omitted, will get extensions for the current class

bool $includeArgumentString

Include the argument string in the return array, FALSE would return array("Versioned"), TRUE returns array("Versioned('Stage','Live')").

Return Value

array

Numeric array of either {@link DataExtension} class names, or eval'ed class name strings with constructor arguments.

static array|null get_extra_config_sources(string $class = null)

Get extra config sources for this class

Parameters

string $class

Name of class. If left null will return for the current class

Return Value

array|null

static bool has_extension(string $classOrExtension, string $requiredExtension = null, bool $strict = false)

Return TRUE if a class has a specified extension.

This supports backwards-compatible format (static Object::has_extension($requiredExtension)) and new format ($object->has_extension($class, $requiredExtension))

Parameters

string $classOrExtension

Class to check extension for, or the extension name to check if the second argument is null.

string $requiredExtension

If the first argument is the parent class, this is the extension to check. If left null, the first parameter will be treated as the extension.

bool $strict

if the extension has to match the required extension and not be a subclass

Return Value

bool

Flag if the extension exists

array invokeWithExtensions(string $method, mixed ...$arguments)

Calls a method if available on both this object and all applied {@link Extensions}, and then attempts to merge all results into an array

Parameters

string $method

the method name to call

mixed ...$arguments

List of arguments

Return Value

array

List of results with nulls filtered out

array extend(string $method, mixed ...$arguments)

Run the given function on all of this object's extensions. Note that this method originally returned void, so if you wanted to return results, you're hosed

Currently returns an array, with an index resulting every time the function is called. Only adds returns if they're not NULL, to avoid bogus results from methods just defined on the parent extension. This is important for permission-checks through extend, as they use min() to determine if any of the returns is FALSE. As min() doesn't do type checking, an included NULL return would fail the permission checks.

The extension methods are defined during {@link __construct()} in {@link defineMethods()}.

Parameters

string $method

the name of the method to call on each extension

mixed ...$arguments

Return Value

array

Extension|null getExtensionInstance(string $extension)

Get an extension instance attached to this object by name.

Parameters

string $extension

Return Value

Extension|null

bool hasExtension(string $extension)

Returns TRUE if this object instance has a specific extension applied in {@link $extension_instances}. Extension instances are initialized at constructor time, meaning if you use {@link add_extension()} afterwards, the added extension will just be added to new instances of the extended class. Use the static method {@link has_extension()} to check if a class (not an instance) has a specific extension.

Caution: Don't use singleton()->hasExtension() as it will give you inconsistent results based on when the singleton was first accessed.

Parameters

string $extension

Classname of an {@link Extension} subclass without parameters

Return Value

bool

Extension[] getExtensionInstances()

Get all extension instances for this specific object instance.

See {@link get_extensions()} to get all applied extension classes for this class (not the instance).

This method also provides lazy-population of the extension_instances property.

Return Value

Extension[]

Map of {@link DataExtension} instances, keyed by classname.

__construct()

run(HTTPRequest $request)

Implement this method in the task subclass to execute via the TaskRunner

Parameters

HTTPRequest $request

bool isEnabled()

Return Value

bool

string getTitle()

Return Value

string

string getDescription()

Return Value

string

HTML formatted description

up()

down()