Implemented an easy to use APIFilter for tags

This makes the process of filters more easily and intuitive. This fixes issue #750

src/ApiPlatform/Filter/TagFilter.php

@@ -0,0 +1,102 @@
+<?php
+/*
+ * This file is part of Part-DB (https://github.com/Part-DB/Part-DB-symfony).
+ *
+ *  Copyright (C) 2019 - 2024 Jan Böhmer (https://github.com/jbtronics)
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Affero General Public License as published
+ *  by the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Affero General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Affero General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+declare(strict_types=1);
+
+
+namespace App\ApiPlatform\Filter;
+
+use ApiPlatform\Doctrine\Orm\Filter\AbstractFilter;
+use ApiPlatform\Doctrine\Orm\Util\QueryNameGeneratorInterface;
+use ApiPlatform\Metadata\Operation;
+use Doctrine\ORM\QueryBuilder;
+use Symfony\Component\PropertyInfo\Type;
+
+/**
+ * Due to their nature, tags are stored in a single string, separated by commas, which requires some more complex search logic.
+ * This filter allows to easily search for tags in a part entity.
+ */
+final class TagFilter extends AbstractFilter
+{
+
+    protected function filterProperty(
+        string $property,
+        $value,
+        QueryBuilder $queryBuilder,
+        QueryNameGeneratorInterface $queryNameGenerator,
+        string $resourceClass,
+        ?Operation $operation = null,
+        array $context = []
+    ): void {
+        // Ignore filter if property is not enabled or mapped
+        if (
+            !$this->isPropertyEnabled($property, $resourceClass) ||
+            !$this->isPropertyMapped($property, $resourceClass)
+        ) {
+            return;
+        }
+
+        //Escape any %, _ or \ in the tag
+        $value = addcslashes($value, '%_\\');
+
+        $tag_identifier_prefix = $queryNameGenerator->generateParameterName($property);
+
+        $expr = $queryBuilder->expr();
+
+        $tmp = $expr->orX(
+            $expr->like('o.'.$property, ':' . $tag_identifier_prefix . '_1'),
+            $expr->like('o.'.$property, ':' . $tag_identifier_prefix . '_2'),
+            $expr->like('o.'.$property, ':' . $tag_identifier_prefix . '_3'),
+            $expr->eq('o.'.$property, ':' . $tag_identifier_prefix . '_4'),
+        );
+
+        $queryBuilder->andWhere($tmp);
+
+        //Set the parameters for the LIKE expression, in each variation of the tag (so with a comma, at the end, at the beginning, and on both ends, and equaling the tag)
+        $queryBuilder->setParameter($tag_identifier_prefix . '_1', '%,' . $value . ',%');
+        $queryBuilder->setParameter($tag_identifier_prefix . '_2', '%,' . $value);
+        $queryBuilder->setParameter($tag_identifier_prefix . '_3', $value . ',%');
+        $queryBuilder->setParameter($tag_identifier_prefix . '_4', $value);
+    }
+
+    public function getDescription(string $resourceClass): array
+    {
+        if (!$this->properties) {
+            return [];
+        }
+
+        $description = [];
+        foreach (array_keys($this->properties) as $property) {
+            $description[(string)$property] = [
+                'property' => $property,
+                'type' => Type::BUILTIN_TYPE_STRING,
+                'required' => false,
+                'description' => 'Filter for tags of a part',
+                'openapi' => [
+                    'example' => '',
+                    'allowReserved' => false,// if true, query parameters will be not percent-encoded
+                    'allowEmptyValue' => true,
+                    'explode' => false, // to be true, the type must be Type::BUILTIN_TYPE_ARRAY, ?product=blue,green will be ?product=blue&product=green
+                ],
+            ];
+        }
+        return $description;
+    }
+}

src/DataTables/Filters/Constraints/Part/TagsConstraint.php

@@ -85,6 +85,9 @@ class TagsConstraint extends AbstractConstraint
      */
     protected function getExpressionForTag(QueryBuilder $queryBuilder, string $tag): Orx
     {
+        //Escape any %, _ or \ in the tag
+        $tag = addcslashes($tag, '%_\\');
+
         $tag_identifier_prefix = uniqid($this->identifier . '_', false);
 
         $expr = $queryBuilder->expr();

src/Entity/Parts/Part.php

@@ -22,6 +22,7 @@ declare(strict_types=1);
 
 namespace App\Entity\Parts;
 
+use App\ApiPlatform\Filter\TagFilter;
 use Doctrine\Common\Collections\Criteria;
 use ApiPlatform\Doctrine\Common\Filter\DateFilterInterface;
 use ApiPlatform\Doctrine\Orm\Filter\BooleanFilter;
@@ -97,7 +98,8 @@ use Symfony\Component\Validator\Context\ExecutionContextInterface;
 #[ApiFilter(PropertyFilter::class)]
 #[ApiFilter(EntityFilter::class, properties: ["category", "footprint", "manufacturer", "partUnit"])]
 #[ApiFilter(PartStoragelocationFilter::class, properties: ["storage_location"])]
-#[ApiFilter(LikeFilter::class, properties: ["name", "comment", "description", "ipn", "tags", "manufacturer_product_number"])]
+#[ApiFilter(LikeFilter::class, properties: ["name", "comment", "description", "ipn", "manufacturer_product_number"])]
+#[ApiFilter(TagFilter::class, properties: ["tags"])]
 #[ApiFilter(BooleanFilter::class, properties: ["favorite" , "needs_review"])]
 #[ApiFilter(RangeFilter::class, properties: ["mass", "minamount"])]
 #[ApiFilter(DateFilter::class, strategy: DateFilterInterface::EXCLUDE_NULL)]