{ "uuid": [ { "value": "166d5baa-74b2-498c-b2cf-a15ddf4df6a0" } ], "langcode": [ { "value": "en" } ], "type": [ { "target_id": "daily_email", "target_type": "node_type", "target_uuid": "8bde1f2f-eef9-4f2d-ae9c-96921f8193d7" } ], "revision_timestamp": [ { "value": "2025-05-11T09:00:50+00:00" } ], "revision_uid": [ { "target_type": "user", "target_uuid": "b8966985-d4b2-42a7-a319-2e94ccfbb849" } ], "revision_log": [], "status": [ { "value": true } ], "uid": [ { "target_type": "user", "target_uuid": "b8966985-d4b2-42a7-a319-2e94ccfbb849" } ], "title": [ { "value": "The Decorator design pattern\n" } ], "created": [ { "value": "2022-12-08T00:00:00+00:00" } ], "changed": [ { "value": "2025-05-11T09:00:50+00:00" } ], "promote": [ { "value": false } ], "sticky": [ { "value": false } ], "default_langcode": [ { "value": true } ], "revision_translation_affected": [ { "value": true } ], "path": [ { "alias": "\/daily\/2022\/12\/08\/the-decorator-design-pattern", "langcode": "en" } ], "body": [ { "value": "\n

Decorator is a structural design pattern that allows you to add extra functionality, such as if you want to add caching or logging to a service, without changing the original class.<\/p>\n\n

As long as a class implements an Interface, it can be decorated.<\/p>\n\n

For example, if I have this PHP interface:<\/p>\n\n

interface DoesSomething\n{\n    public function doSomething(): void;\n}\n<\/code><\/pre>\n\n

I could have this class that does something:<\/p>\n\n

final class FirstClass implements DoesSomething\n{\n    public function doSomething(): void\n    {\n        \/\/ Does something.\n    }\n}\n<\/code><\/pre>\n\n

If I need to do something else, like caching or logging the result, I can decorate it.<\/p>\n\n

To do this, I need another class that implements the same interface and inject the original version.<\/p>\n\n

final class SecondClass implements DoesSomething\n{\n    public function __constuct(\n        private DoesSomething $originalClass\n   ) {}\n\n    public function doSomething()\n    {\n        \/\/ Do something else before.\n\n        $this->originalClass->doSomething();\n\n        \/\/ Do something else afterwards.\n    }\n}\n<\/code><\/pre>\n\n

Within the new class, the methods can be overridden, extra functionality can be added, and the original method can be run to execute the original functionality.<\/p>\n\n

As the two classes implement the same interface, I can swap between different versions and decorate multiple times if needed.<\/p>\n\n

This a pattern that I used recently to extend a service that retrieved some data from an API and saved it to a file, to change some arguments and do more work with it.<\/p>\n\n

The original class was unchanged, the new class was minimal and easy to understand as it only had a single responsibility, and if I needed to switch back to the original version, I could easily do that.<\/p>\n\n ", "format": "full_html", "processed": "\n

Decorator is a structural design pattern that allows you to add extra functionality, such as if you want to add caching or logging to a service, without changing the original class.<\/p>\n\n

As long as a class implements an Interface, it can be decorated.<\/p>\n\n

For example, if I have this PHP interface:<\/p>\n\n

interface DoesSomething\n{\n    public function doSomething(): void;\n}\n<\/code><\/pre>\n\n

I could have this class that does something:<\/p>\n\n

final class FirstClass implements DoesSomething\n{\n    public function doSomething(): void\n    {\n        \/\/ Does something.\n    }\n}\n<\/code><\/pre>\n\n

If I need to do something else, like caching or logging the result, I can decorate it.<\/p>\n\n

To do this, I need another class that implements the same interface and inject the original version.<\/p>\n\n

final class SecondClass implements DoesSomething\n{\n    public function __constuct(\n        private DoesSomething $originalClass\n   ) {}\n\n    public function doSomething()\n    {\n        \/\/ Do something else before.\n\n        $this->originalClass->doSomething();\n\n        \/\/ Do something else afterwards.\n    }\n}\n<\/code><\/pre>\n\n

Within the new class, the methods can be overridden, extra functionality can be added, and the original method can be run to execute the original functionality.<\/p>\n\n

As the two classes implement the same interface, I can swap between different versions and decorate multiple times if needed.<\/p>\n\n

This a pattern that I used recently to extend a service that retrieved some data from an API and saved it to a file, to change some arguments and do more work with it.<\/p>\n\n

The original class was unchanged, the new class was minimal and easy to understand as it only had a single responsibility, and if I needed to switch back to the original version, I could easily do that.<\/p>\n\n ", "summary": null } ] }