WIP: Create an abstraction layer for the database

.github/actions/run-tests/tests/test-entrypoint.sh

@@ -121,7 +121,7 @@ else
 
 	echo 'Copying the app code changes'
 	echo 'This might cause trouble when dependencies have changed'
-	rsync -a /app/ apps/cookbook/ --exclude /.git --exclude /build --exclude /.github
+	rsync -a /app/ apps/cookbook/ --exclude /.git --exclude /build --exclude /.github --exclude /vendor
 
 fi
 

CHANGELOG.md

@@ -1,5 +1,9 @@
 ## [Unreleased]
 
+### Added
+- Database abstraction added for simpler access
+  [#407](https://github.com/nextcloud/cookbook/pull/407) @christianlupus
+
 ## 0.7.9 - 2021-01-15
 
 ### Changed

documentation/uml/dbwrappers.txt

@@ -0,0 +1,216 @@
+@startuml
+
+namespace OCA.Cookbook {
+
+	namespace Entity {
+
+		interface Entity {
+			+ persist() : void
+			+ remove() : void
+			+ reload() : void
+		}
+
+		interface RecipeEntity {
+			--
+			+ getId() : int
+			+ getName() : string
+			+ setName(string) : void
+			..
+			+ getCategory() : CategoryEntity
+			+ setCategory(CategoryEntity) : void
+			+ getKeywords() : array
+			+ addKeyword(KeywordEntity) : void
+			+ removeKeyword(KeywordEntity) : void
+		}
+
+		interface CategoryEntity {
+			--
+			+ getName() : string
+			+ setName(string) : void
+			..
+			+ getRecipes() : array
+		}
+
+		interface KeywordEntity {
+			--
+			+ getName() : string
+			+ setName(string) : void
+			..
+			+ getRecipes() : array
+		}
+
+
+		namespace impl {
+
+			abstract class AbstractEntity {
+				- bool persisted
+				+ isPersisted() : bool
+				+ abstract clone() : ImplEntity
+				+ abstract isSame(AbstractEntity) : bool
+				+ abstract equals(AbstractEntity) : bool
+			}
+
+			class RecipeEntityImpl {
+				#id
+				#name
+				#userId
+				# RecipeDbWrapper wrapper
+				# CategoryEntityImpl newCategory
+				# array newKeywords
+				# array removedKeywords
+				+ getNewCategory() : CategoryEntityImpl | null
+				+ getNewKeywords() : array
+				+ getRemovedKeywords() : array
+			}
+
+			class CategoryEntityImpl {
+				#name
+				# CategoryDbWrapper wrapper
+			}
+
+			class KeywordEntityImpl {
+				#name
+				# KeywordDbWrapper wrapper
+			}
+
+			class CategoryMappingEntity {
+			}
+
+			class KeywordMappingEntity {
+			}
+
+			RecipeEntityImpl --|> AbstractEntity
+			CategoryEntityImpl --|> AbstractEntity
+			KeywordEntityImpl --|> AbstractEntity
+
+			CategoryMappingEntity -|> AbstractEntity
+			AbstractEntity <|- KeywordMappingEntity
+
+			RecipeEntityImpl "1" *--x CategoryMappingEntity
+			RecipeEntityImpl "1" *--x KeywordMappingEntity
+			CategoryEntityImpl "1" *--x CategoryMappingEntity
+			KeywordEntityImpl "1" *--x KeywordMappingEntity
+
+		}
+
+		RecipeEntity <|.. OCA.Cookbook.Entity.impl.RecipeEntityImpl
+		CategoryEntity <|.. OCA.Cookbook.Entity.impl.CategoryEntityImpl
+		KeywordEntity <|.. OCA.Cookbook.Entity.impl.KeywordEntityImpl
+
+		Entity <|.. RecipeEntity
+		Entity <|.. CategoryEntity
+		Entity <|.. KeywordEntity
+
+		namespace Collections {
+
+			abstract class AbstractCollection<T extends Entity> {}
+			class Recipes {}
+			class Categories {}
+			class Keywords {}
+
+
+			AbstractCollection <|-- Recipes
+			AbstractCollection <|-- Categories
+			AbstractCollection <|-- Keywords
+		}
+
+	}
+
+	namespace Db {
+
+		abstract class AbstractDbWrapper {
+			# IDbConnection db
+			- array cache
+			- bool cacheValid
+			+ abstract createEntity() : T
+			# abstract fetchDatabase() : array
+			+ getEntites() : array
+			# setCache(array) : void
+			+ getServiceLocator() : DbWrapperSerciveLocator
+		}
+		note right
+		Cache represents the current state
+		of the database tables as clones.
+		endnote
+
+		class RecipeDbWrapper {
+'			- array idMap
+			--
+			+ createEntity() : RecipeEntityImpl
+			+ store(RecipeEntityImpl) : void
+			# storeNew(RecipeEntityImpl) : void
+			# update(RecipeEntityImpl) : void
+			+ remove(RecipeEntityImpl) : void
+			..
+			/'+ addKeyword(RecipeEntityImpl, KeywordEntityImpl) : KeywordMappingEntity
+			+ setCategory(RecipeEntityImpl, CategoryEntityImpl) : CategoryMappingEntity'/
+			+ getCategory(RecipeEntityImpl) : CategoryEntityImpl
+			+ getKeywords(RecipeEntityImpl) : array
+		}
+		class CategoryDbWrapper {
+			--
+			+ createEntity() : CategoryEntityImpl
+			+ store(CategoryEntityImpl) : void
+			# storeNew(CategoryEntityImpl) : void
+			# update(CategoryEntityImpl) : void
+			+ remove(CategoryEntityImpl) : void
+			..
+			+ getRecipes(CategoryEntityImpl) : array
+		}
+		class KeywordDbWrapper {
+			--
+			+ createEntity() : KeywordEntityImpl
+			+ store(KeywordEntityImpl) : void
+			# storeNew(KeywordEntityImpl) : void
+			# update(KeywordEntityImpl) : void
+			+ remove(KeywordEntityImpl) : void
+			..
+			+ getRecipes(KeywordEntityImpl) : array
+		}
+
+		class CategoryMappingsDbWrapper {
+			+ createEntity() : CategoryMappingEntity
+			+ store(CategoryMappingEntity) : void
+			# storeNew(CategoryMappingEntity) : void
+			# update(CategoryMappingEntity) : void
+			+ remove(CategoryMappingEntity) : void
+		}
+
+		class KeywordMappingsDbWrapper {
+			+ createEntity() : KeywordMappingEntity
+			+ store(KeywordMappingEntity) : void
+			# storeNew(KeywordMappingEntity) : void
+			# update(KeywordMappingEntity) : void
+			+ remove(KeywordMappingEntity) : void
+		}
+
+		class DbWrapperSerciveLocator {
+			+ getRecipeDbWrapoper() : RecipeDbWrapper
+			+ getCategoryDbWrapper() : CategoryDbWrapper
+			+ getKeywordDbWrapper() : KeywordDbWrapper
+			+ getKeywordMappingDbWrapper() : KeywordMappingsDbWrapper
+			+ getCategoryMappingDbWrapper() : CategoryMappingsDbWrapper
+		}
+
+		AbstractDbWrapper <|-- RecipeDbWrapper
+		AbstractDbWrapper <|-- CategoryDbWrapper
+		AbstractDbWrapper <|-- KeywordDbWrapper
+
+		RecipeDbWrapper "1" o-- "1" DbWrapperSerciveLocator
+		CategoryDbWrapper "1" o-- "1" DbWrapperSerciveLocator
+		KeywordDbWrapper "1" o-- "1" DbWrapperSerciveLocator
+
+		CategoryMappingsDbWrapper "1" o- "1" DbWrapperSerciveLocator
+		DbWrapperSerciveLocator "1" -o "1" KeywordMappingsDbWrapper
+
+		AbstractDbWrapper <|--- CategoryMappingsDbWrapper
+		AbstractDbWrapper <|--- KeywordMappingsDbWrapper
+
+		DbWrapperSerciveLocator -[hidden]-> AbstractDbWrapper
+	}
+
+}
+
+ArrayIterator <|-- OCA.Cookbook.Entity.Collections.AbstractCollection
+
+@enduml

lib/Db/AbstractDbWrapper.php

@@ -0,0 +1,104 @@
+<?php
+
+namespace OCA\Cookbook\Db;
+
+use OCP\IDBConnection;
+
+abstract class AbstractDbWrapper {
+
+	/**
+	 * @var array
+	 */
+	private $cache;
+
+	/**
+	 * @var bool
+	 */
+	private $initialized;
+
+	/**
+	 * @var IDBConnection
+	 */
+	private $db;
+
+	/**
+	 * @var DbWrapperServiceProvider
+	 */
+	protected $wrapperLocator;
+
+	public function __construct(IDBConnection $db) {
+		$this->initialized = false;
+		$this->db = $db;
+	}
+
+	/**
+	 * Fetch all elements from the database.
+	 *
+	 * The concrete class must implemnt a way to fetch an array or elements represented by the database.
+	 * @return array The (possible empty) array of entities in the database
+	 */
+	abstract protected function fetchDatabase(): array;
+
+	/**
+	 * Fetch the entries in the database
+	 *
+	 * If the cache has already been fetched, the values in the cache are returned.
+	 *
+	 * @return array The entities in the database.
+	 */
+	public function getEntries(): array {
+		if (! $this->initialized) {
+			$this->reloadCache();
+		}
+
+		return $this->cache;
+	}
+
+	/**
+	 * Reload the cache from the database.
+	 */
+	private function reloadCache(): void {
+		$this->cache = $this->fetchDatabase();
+		$this->initialized = true;
+	}
+
+	/**
+	 * Invalidate the local cache.
+	 *
+	 * This will cause any access to the entities to refetch the whole cache.
+	 */
+	protected function invalidateCache(): void {
+		$this->initialized = false;
+	}
+
+	/**
+	 * Set the cache to the given array.
+	 *
+	 * This function will repace the current cache by the given array.
+	 * No further checks are carried out.
+	 * Please be very careful to provide the most up to date data as present in the database.
+	 * Otherwise you will see very strange effects.
+	 *
+	 * @param array $entities The new entities of the cache
+	 */
+	protected function setEntites(array $entities): void {
+		$this->cache = $entities;
+		$this->initialized = true;
+	}
+
+	/**
+	 * Set the central service locator for registering of all wrappers
+	 * @param DbWrapperServiceProvider $locator The locator for the registered wrappers
+	 */
+	public function setWrapperServiceLocator(DbWrapperServiceProvider $locator) {
+		$this->wrapperLocator = $locator;
+	}
+
+	/**
+	 * Get the central service locator for registering of all wrappers
+	 * @return DbWrapperServiceProvider The locator for the registered wrappers
+	 */
+	public function getWrapperServiceLocator() {
+		return $this->wrapperLocator;
+	}
+}