nextcloud / server

apps/dav/lib/Files/FileSearchBackend.php

Indentation +378 added lines, -378 removed lines

@@ -53,382 +53,382 @@
 use SearchDAV\Query\Query;
 
 class FileSearchBackend implements ISearchBackend {
-	/** @var CachingTree */
-	private $tree;
-
-	/** @var IUser */
-	private $user;
-
-	/** @var IRootFolder */
-	private $rootFolder;
-
-	/** @var IManager */
-	private $shareManager;
-
-	/** @var View */
-	private $view;
-
-	/**
-	 * FileSearchBackend constructor.
-	 *
-	 * @param CachingTree $tree
-	 * @param IUser $user
-	 * @param IRootFolder $rootFolder
-	 * @param IManager $shareManager
-	 * @param View $view
-	 * @internal param IRootFolder $rootFolder
-	 */
-	public function __construct(CachingTree $tree, IUser $user, IRootFolder $rootFolder, IManager $shareManager, View $view) {
-		$this->tree = $tree;
-		$this->user = $user;
-		$this->rootFolder = $rootFolder;
-		$this->shareManager = $shareManager;
-		$this->view = $view;
-	}
-
-	/**
-	 * Search endpoint will be remote.php/dav
-	 *
-	 * @return string
-	 */
-	public function getArbiterPath() {
-		return '';
-	}
-
-	public function isValidScope($href, $depth, $path) {
-		// only allow scopes inside the dav server
-		if (is_null($path)) {
-			return false;
-		}
-
-		try {
-			$node = $this->tree->getNodeForPath($path);
-			return $node instanceof Directory;
-		} catch (NotFound $e) {
-			return false;
-		}
-	}
-
-	public function getPropertyDefinitionsForScope($href, $path) {
-		// all valid scopes support the same schema
-
-		//todo dynamically load all propfind properties that are supported
-		return [
-			// queryable properties
-			new SearchPropertyDefinition('{DAV:}displayname', true, true, true),
-			new SearchPropertyDefinition('{DAV:}getcontenttype', true, true, true),
-			new SearchPropertyDefinition('{DAV:}getlastmodified', true, true, true, SearchPropertyDefinition::DATATYPE_DATETIME),
-			new SearchPropertyDefinition(FilesPlugin::SIZE_PROPERTYNAME, true, true, true, SearchPropertyDefinition::DATATYPE_NONNEGATIVE_INTEGER),
-			new SearchPropertyDefinition(TagsPlugin::FAVORITE_PROPERTYNAME, true, true, true, SearchPropertyDefinition::DATATYPE_BOOLEAN),
-			new SearchPropertyDefinition(FilesPlugin::INTERNAL_FILEID_PROPERTYNAME, true, true, false, SearchPropertyDefinition::DATATYPE_NONNEGATIVE_INTEGER),
-			new SearchPropertyDefinition(FilesPlugin::OWNER_ID_PROPERTYNAME, true, true, false),
-
-			// select only properties
-			new SearchPropertyDefinition('{DAV:}resourcetype', false, true, false),
-			new SearchPropertyDefinition('{DAV:}getcontentlength', false, true, false),
-			new SearchPropertyDefinition(FilesPlugin::CHECKSUMS_PROPERTYNAME, false, true, false),
-			new SearchPropertyDefinition(FilesPlugin::PERMISSIONS_PROPERTYNAME, false, true, false),
-			new SearchPropertyDefinition(FilesPlugin::GETETAG_PROPERTYNAME, false, true, false),
-			new SearchPropertyDefinition(FilesPlugin::OWNER_DISPLAY_NAME_PROPERTYNAME, false, true, false),
-			new SearchPropertyDefinition(FilesPlugin::DATA_FINGERPRINT_PROPERTYNAME, false, true, false),
-			new SearchPropertyDefinition(FilesPlugin::HAS_PREVIEW_PROPERTYNAME, false, true, false, SearchPropertyDefinition::DATATYPE_BOOLEAN),
-			new SearchPropertyDefinition(FilesPlugin::FILEID_PROPERTYNAME, false, true, false, SearchPropertyDefinition::DATATYPE_NONNEGATIVE_INTEGER),
-		];
-	}
-
-	/**
-	 * @param Query $search
-	 * @return SearchResult[]
-	 */
-	public function search(Query $search) {
-		if (count($search->from) !== 1) {
-			throw new \InvalidArgumentException('Searching more than one folder is not supported');
-		}
-		$query = $this->transformQuery($search);
-		$scope = $search->from[0];
-		if ($scope->path === null) {
-			throw new \InvalidArgumentException('Using uri\'s as scope is not supported, please use a path relative to the search arbiter instead');
-		}
-		$node = $this->tree->getNodeForPath($scope->path);
-		if (!$node instanceof Directory) {
-			throw new \InvalidArgumentException('Search is only supported on directories');
-		}
-
-		$fileInfo = $node->getFileInfo();
-		$folder = $this->rootFolder->get($fileInfo->getPath());
-		/** @var Folder $folder $results */
-		$results = $folder->search($query);
-
-		/** @var SearchResult[] $nodes */
-		$nodes = array_map(function (Node $node) {
-			if ($node instanceof Folder) {
-				$davNode = new \OCA\DAV\Connector\Sabre\Directory($this->view, $node, $this->tree, $this->shareManager);
-			} else {
-				$davNode = new \OCA\DAV\Connector\Sabre\File($this->view, $node, $this->shareManager);
-			}
-			$path = $this->getHrefForNode($node);
-			$this->tree->cacheNode($davNode, $path);
-			return new SearchResult($davNode, $path);
-		}, $results);
-
-		if (!$query->limitToHome()) {
-			// Sort again, since the result from multiple storages is appended and not sorted
-			usort($nodes, function (SearchResult $a, SearchResult $b) use ($search) {
-				return $this->sort($a, $b, $search->orderBy);
-			});
-		}
-
-		// If a limit is provided use only return that number of files
-		if ($search->limit->maxResults !== 0) {
-			$nodes = \array_slice($nodes, 0, $search->limit->maxResults);
-		}
-
-		return $nodes;
-	}
-
-	private function sort(SearchResult $a, SearchResult $b, array $orders) {
-		/** @var Order $order */
-		foreach ($orders as $order) {
-			$v1 = $this->getSearchResultProperty($a, $order->property);
-			$v2 = $this->getSearchResultProperty($b, $order->property);
-
-
-			if ($v1 === null && $v2 === null) {
-				continue;
-			}
-			if ($v1 === null) {
-				return $order->order === Order::ASC ? 1 : -1;
-			}
-			if ($v2 === null) {
-				return $order->order === Order::ASC ? -1 : 1;
-			}
-
-			$s = $this->compareProperties($v1, $v2, $order);
-			if ($s === 0) {
-				continue;
-			}
-
-			if ($order->order === Order::DESC) {
-				$s = -$s;
-			}
-			return $s;
-		}
-
-		return 0;
-	}
-
-	private function compareProperties($a, $b, Order $order) {
-		switch ($order->property->dataType) {
-			case SearchPropertyDefinition::DATATYPE_STRING:
-				return strcmp($a, $b);
-			case SearchPropertyDefinition::DATATYPE_BOOLEAN:
-				if ($a === $b) {
-					return 0;
-				}
-				if ($a === false) {
-					return -1;
-				}
-				return 1;
-			default:
-				if ($a === $b) {
-					return 0;
-				}
-				if ($a < $b) {
-					return -1;
-				}
-				return 1;
-		}
-	}
-
-	private function getSearchResultProperty(SearchResult $result, SearchPropertyDefinition $property) {
-		/** @var \OCA\DAV\Connector\Sabre\Node $node */
-		$node = $result->node;
-
-		switch ($property->name) {
-			case '{DAV:}displayname':
-				return $node->getName();
-			case '{DAV:}getlastmodified':
-				return $node->getLastModified();
-			case FilesPlugin::SIZE_PROPERTYNAME:
-				return $node->getSize();
-			case FilesPlugin::INTERNAL_FILEID_PROPERTYNAME:
-				return $node->getInternalFileId();
-			default:
-				return null;
-		}
-	}
-
-	/**
-	 * @param Node $node
-	 * @return string
-	 */
-	private function getHrefForNode(Node $node) {
-		$base = '/files/' . $this->user->getUID();
-		return $base . $this->view->getRelativePath($node->getPath());
-	}
-
-	/**
-	 * @param Query $query
-	 * @return ISearchQuery
-	 */
-	private function transformQuery(Query $query): ISearchQuery {
-		$limit = $query->limit;
-		$orders = array_map([$this, 'mapSearchOrder'], $query->orderBy);
-		$offset = $limit->firstResult;
-
-		$limitHome = false;
-		$ownerProp = $this->extractWhereValue($query->where, FilesPlugin::OWNER_ID_PROPERTYNAME, Operator::OPERATION_EQUAL);
-		if ($ownerProp !== null) {
-			if ($ownerProp === $this->user->getUID()) {
-				$limitHome = true;
-			} else {
-				throw new \InvalidArgumentException("Invalid search value for '{http://owncloud.org/ns}owner-id', only the current user id is allowed");
-			}
-		}
-
-		return new SearchQuery(
-			$this->transformSearchOperation($query->where),
-			(int)$limit->maxResults,
-			$offset,
-			$orders,
-			$this->user,
-			$limitHome
-		);
-	}
-
-	/**
-	 * @param Order $order
-	 * @return ISearchOrder
-	 */
-	private function mapSearchOrder(Order $order) {
-		return new SearchOrder($order->order === Order::ASC ? ISearchOrder::DIRECTION_ASCENDING : ISearchOrder::DIRECTION_DESCENDING, $this->mapPropertyNameToColumn($order->property));
-	}
-
-	/**
-	 * @param Operator $operator
-	 * @return ISearchOperator
-	 */
-	private function transformSearchOperation(Operator $operator) {
-		[, $trimmedType] = explode('}', $operator->type);
-		switch ($operator->type) {
-			case Operator::OPERATION_AND:
-			case Operator::OPERATION_OR:
-			case Operator::OPERATION_NOT:
-				$arguments = array_map([$this, 'transformSearchOperation'], $operator->arguments);
-				return new SearchBinaryOperator($trimmedType, $arguments);
-			case Operator::OPERATION_EQUAL:
-			case Operator::OPERATION_GREATER_OR_EQUAL_THAN:
-			case Operator::OPERATION_GREATER_THAN:
-			case Operator::OPERATION_LESS_OR_EQUAL_THAN:
-			case Operator::OPERATION_LESS_THAN:
-			case Operator::OPERATION_IS_LIKE:
-				if (count($operator->arguments) !== 2) {
-					throw new \InvalidArgumentException('Invalid number of arguments for ' . $trimmedType . ' operation');
-				}
-				if (!($operator->arguments[0] instanceof SearchPropertyDefinition)) {
-					throw new \InvalidArgumentException('Invalid argument 1 for ' . $trimmedType . ' operation, expected property');
-				}
-				if (!($operator->arguments[1] instanceof Literal)) {
-					throw new \InvalidArgumentException('Invalid argument 2 for ' . $trimmedType . ' operation, expected literal');
-				}
-				return new SearchComparison($trimmedType, $this->mapPropertyNameToColumn($operator->arguments[0]), $this->castValue($operator->arguments[0], $operator->arguments[1]->value));
-			case Operator::OPERATION_IS_COLLECTION:
-				return new SearchComparison('eq', 'mimetype', ICacheEntry::DIRECTORY_MIMETYPE);
-			default:
-				throw new \InvalidArgumentException('Unsupported operation ' . $trimmedType . ' (' . $operator->type . ')');
-		}
-	}
-
-	/**
-	 * @param SearchPropertyDefinition $property
-	 * @return string
-	 */
-	private function mapPropertyNameToColumn(SearchPropertyDefinition $property) {
-		switch ($property->name) {
-			case '{DAV:}displayname':
-				return 'name';
-			case '{DAV:}getcontenttype':
-				return 'mimetype';
-			case '{DAV:}getlastmodified':
-				return 'mtime';
-			case FilesPlugin::SIZE_PROPERTYNAME:
-				return 'size';
-			case TagsPlugin::FAVORITE_PROPERTYNAME:
-				return 'favorite';
-			case TagsPlugin::TAGS_PROPERTYNAME:
-				return 'tagname';
-			case FilesPlugin::INTERNAL_FILEID_PROPERTYNAME:
-				return 'fileid';
-			default:
-				throw new \InvalidArgumentException('Unsupported property for search or order: ' . $property->name);
-		}
-	}
-
-	private function castValue(SearchPropertyDefinition $property, $value) {
-		switch ($property->dataType) {
-			case SearchPropertyDefinition::DATATYPE_BOOLEAN:
-				return $value === 'yes';
-			case SearchPropertyDefinition::DATATYPE_DECIMAL:
-			case SearchPropertyDefinition::DATATYPE_INTEGER:
-			case SearchPropertyDefinition::DATATYPE_NONNEGATIVE_INTEGER:
-				return 0 + $value;
-			case SearchPropertyDefinition::DATATYPE_DATETIME:
-				if (is_numeric($value)) {
-					return max(0, 0 + $value);
-				}
-				$date = \DateTime::createFromFormat(\DateTime::ATOM, $value);
-				return ($date instanceof \DateTime && $date->getTimestamp() !== false) ? $date->getTimestamp() : 0;
-			default:
-				return $value;
-		}
-	}
-
-	/**
-	 * Get a specific property from the were clause
-	 */
-	private function extractWhereValue(Operator &$operator, string $propertyName, string $comparison, bool $acceptableLocation = true): ?string {
-		switch ($operator->type) {
-			case Operator::OPERATION_AND:
-			case Operator::OPERATION_OR:
-			case Operator::OPERATION_NOT:
-				foreach ($operator->arguments as &$argument) {
-					$value = $this->extractWhereValue($argument, $propertyName, $comparison, $acceptableLocation && $operator->type === Operator::OPERATION_AND);
-					if ($value !== null) {
-						return $value;
-					}
-				}
-				return null;
-			case Operator::OPERATION_EQUAL:
-			case Operator::OPERATION_GREATER_OR_EQUAL_THAN:
-			case Operator::OPERATION_GREATER_THAN:
-			case Operator::OPERATION_LESS_OR_EQUAL_THAN:
-			case Operator::OPERATION_LESS_THAN:
-			case Operator::OPERATION_IS_LIKE:
-				if ($operator->arguments[0]->name === $propertyName) {
-					if ($operator->type === $comparison) {
-						if ($acceptableLocation) {
-							if ($operator->arguments[1] instanceof Literal) {
-								$value = $operator->arguments[1]->value;
-
-								// to remove the comparison from the query, we replace it with an empty AND
-								$operator = new Operator(Operator::OPERATION_AND);
-
-								return $value;
-							} else {
-								throw new \InvalidArgumentException("searching by '$propertyName' is only allowed with a literal value");
-							}
-						} else {
-							throw new \InvalidArgumentException("searching by '$propertyName' is not allowed inside a '{DAV:}or' or '{DAV:}not'");
-						}
-					} else {
-						throw new \InvalidArgumentException("searching by '$propertyName' is only allowed inside a '$comparison'");
-					}
-				} else {
-					return null;
-				}
-				// no break
-			default:
-				return null;
-		}
-	}
+    /** @var CachingTree */
+    private $tree;
+
+    /** @var IUser */
+    private $user;
+
+    /** @var IRootFolder */
+    private $rootFolder;
+
+    /** @var IManager */
+    private $shareManager;
+
+    /** @var View */
+    private $view;
+
+    /**
+     * FileSearchBackend constructor.
+     *
+     * @param CachingTree $tree
+     * @param IUser $user
+     * @param IRootFolder $rootFolder
+     * @param IManager $shareManager
+     * @param View $view
+     * @internal param IRootFolder $rootFolder
+     */
+    public function __construct(CachingTree $tree, IUser $user, IRootFolder $rootFolder, IManager $shareManager, View $view) {
+        $this->tree = $tree;
+        $this->user = $user;
+        $this->rootFolder = $rootFolder;
+        $this->shareManager = $shareManager;
+        $this->view = $view;
+    }
+
+    /**
+     * Search endpoint will be remote.php/dav
+     *
+     * @return string
+     */
+    public function getArbiterPath() {
+        return '';
+    }
+
+    public function isValidScope($href, $depth, $path) {
+        // only allow scopes inside the dav server
+        if (is_null($path)) {
+            return false;
+        }
+
+        try {
+            $node = $this->tree->getNodeForPath($path);
+            return $node instanceof Directory;
+        } catch (NotFound $e) {
+            return false;
+        }
+    }
+
+    public function getPropertyDefinitionsForScope($href, $path) {
+        // all valid scopes support the same schema
+
+        //todo dynamically load all propfind properties that are supported
+        return [
+            // queryable properties
+            new SearchPropertyDefinition('{DAV:}displayname', true, true, true),
+            new SearchPropertyDefinition('{DAV:}getcontenttype', true, true, true),
+            new SearchPropertyDefinition('{DAV:}getlastmodified', true, true, true, SearchPropertyDefinition::DATATYPE_DATETIME),
+            new SearchPropertyDefinition(FilesPlugin::SIZE_PROPERTYNAME, true, true, true, SearchPropertyDefinition::DATATYPE_NONNEGATIVE_INTEGER),
+            new SearchPropertyDefinition(TagsPlugin::FAVORITE_PROPERTYNAME, true, true, true, SearchPropertyDefinition::DATATYPE_BOOLEAN),
+            new SearchPropertyDefinition(FilesPlugin::INTERNAL_FILEID_PROPERTYNAME, true, true, false, SearchPropertyDefinition::DATATYPE_NONNEGATIVE_INTEGER),
+            new SearchPropertyDefinition(FilesPlugin::OWNER_ID_PROPERTYNAME, true, true, false),
+
+            // select only properties
+            new SearchPropertyDefinition('{DAV:}resourcetype', false, true, false),
+            new SearchPropertyDefinition('{DAV:}getcontentlength', false, true, false),
+            new SearchPropertyDefinition(FilesPlugin::CHECKSUMS_PROPERTYNAME, false, true, false),
+            new SearchPropertyDefinition(FilesPlugin::PERMISSIONS_PROPERTYNAME, false, true, false),
+            new SearchPropertyDefinition(FilesPlugin::GETETAG_PROPERTYNAME, false, true, false),
+            new SearchPropertyDefinition(FilesPlugin::OWNER_DISPLAY_NAME_PROPERTYNAME, false, true, false),
+            new SearchPropertyDefinition(FilesPlugin::DATA_FINGERPRINT_PROPERTYNAME, false, true, false),
+            new SearchPropertyDefinition(FilesPlugin::HAS_PREVIEW_PROPERTYNAME, false, true, false, SearchPropertyDefinition::DATATYPE_BOOLEAN),
+            new SearchPropertyDefinition(FilesPlugin::FILEID_PROPERTYNAME, false, true, false, SearchPropertyDefinition::DATATYPE_NONNEGATIVE_INTEGER),
+        ];
+    }
+
+    /**
+     * @param Query $search
+     * @return SearchResult[]
+     */
+    public function search(Query $search) {
+        if (count($search->from) !== 1) {
+            throw new \InvalidArgumentException('Searching more than one folder is not supported');
+        }
+        $query = $this->transformQuery($search);
+        $scope = $search->from[0];
+        if ($scope->path === null) {
+            throw new \InvalidArgumentException('Using uri\'s as scope is not supported, please use a path relative to the search arbiter instead');
+        }
+        $node = $this->tree->getNodeForPath($scope->path);
+        if (!$node instanceof Directory) {
+            throw new \InvalidArgumentException('Search is only supported on directories');
+        }
+
+        $fileInfo = $node->getFileInfo();
+        $folder = $this->rootFolder->get($fileInfo->getPath());
+        /** @var Folder $folder $results */
+        $results = $folder->search($query);
+
+        /** @var SearchResult[] $nodes */
+        $nodes = array_map(function (Node $node) {
+            if ($node instanceof Folder) {
+                $davNode = new \OCA\DAV\Connector\Sabre\Directory($this->view, $node, $this->tree, $this->shareManager);
+            } else {
+                $davNode = new \OCA\DAV\Connector\Sabre\File($this->view, $node, $this->shareManager);
+            }
+            $path = $this->getHrefForNode($node);
+            $this->tree->cacheNode($davNode, $path);
+            return new SearchResult($davNode, $path);
+        }, $results);
+
+        if (!$query->limitToHome()) {
+            // Sort again, since the result from multiple storages is appended and not sorted
+            usort($nodes, function (SearchResult $a, SearchResult $b) use ($search) {
+                return $this->sort($a, $b, $search->orderBy);
+            });
+        }
+
+        // If a limit is provided use only return that number of files
+        if ($search->limit->maxResults !== 0) {
+            $nodes = \array_slice($nodes, 0, $search->limit->maxResults);
+        }
+
+        return $nodes;
+    }
+
+    private function sort(SearchResult $a, SearchResult $b, array $orders) {
+        /** @var Order $order */
+        foreach ($orders as $order) {
+            $v1 = $this->getSearchResultProperty($a, $order->property);
+            $v2 = $this->getSearchResultProperty($b, $order->property);
+
+
+            if ($v1 === null && $v2 === null) {
+                continue;
+            }
+            if ($v1 === null) {
+                return $order->order === Order::ASC ? 1 : -1;
+            }
+            if ($v2 === null) {
+                return $order->order === Order::ASC ? -1 : 1;
+            }
+
+            $s = $this->compareProperties($v1, $v2, $order);
+            if ($s === 0) {
+                continue;
+            }
+
+            if ($order->order === Order::DESC) {
+                $s = -$s;
+            }
+            return $s;
+        }
+
+        return 0;
+    }
+
+    private function compareProperties($a, $b, Order $order) {
+        switch ($order->property->dataType) {
+            case SearchPropertyDefinition::DATATYPE_STRING:
+                return strcmp($a, $b);
+            case SearchPropertyDefinition::DATATYPE_BOOLEAN:
+                if ($a === $b) {
+                    return 0;
+                }
+                if ($a === false) {
+                    return -1;
+                }
+                return 1;
+            default:
+                if ($a === $b) {
+                    return 0;
+                }
+                if ($a < $b) {
+                    return -1;
+                }
+                return 1;
+        }
+    }
+
+    private function getSearchResultProperty(SearchResult $result, SearchPropertyDefinition $property) {
+        /** @var \OCA\DAV\Connector\Sabre\Node $node */
+        $node = $result->node;
+
+        switch ($property->name) {
+            case '{DAV:}displayname':
+                return $node->getName();
+            case '{DAV:}getlastmodified':
+                return $node->getLastModified();
+            case FilesPlugin::SIZE_PROPERTYNAME:
+                return $node->getSize();
+            case FilesPlugin::INTERNAL_FILEID_PROPERTYNAME:
+                return $node->getInternalFileId();
+            default:
+                return null;
+        }
+    }
+
+    /**
+     * @param Node $node
+     * @return string
+     */
+    private function getHrefForNode(Node $node) {
+        $base = '/files/' . $this->user->getUID();
+        return $base . $this->view->getRelativePath($node->getPath());
+    }
+
+    /**
+     * @param Query $query
+     * @return ISearchQuery
+     */
+    private function transformQuery(Query $query): ISearchQuery {
+        $limit = $query->limit;
+        $orders = array_map([$this, 'mapSearchOrder'], $query->orderBy);
+        $offset = $limit->firstResult;
+
+        $limitHome = false;
+        $ownerProp = $this->extractWhereValue($query->where, FilesPlugin::OWNER_ID_PROPERTYNAME, Operator::OPERATION_EQUAL);
+        if ($ownerProp !== null) {
+            if ($ownerProp === $this->user->getUID()) {
+                $limitHome = true;
+            } else {
+                throw new \InvalidArgumentException("Invalid search value for '{http://owncloud.org/ns}owner-id', only the current user id is allowed");
+            }
+        }
+
+        return new SearchQuery(
+            $this->transformSearchOperation($query->where),
+            (int)$limit->maxResults,
+            $offset,
+            $orders,
+            $this->user,
+            $limitHome
+        );
+    }
+
+    /**
+     * @param Order $order
+     * @return ISearchOrder
+     */
+    private function mapSearchOrder(Order $order) {
+        return new SearchOrder($order->order === Order::ASC ? ISearchOrder::DIRECTION_ASCENDING : ISearchOrder::DIRECTION_DESCENDING, $this->mapPropertyNameToColumn($order->property));
+    }
+
+    /**
+     * @param Operator $operator
+     * @return ISearchOperator
+     */
+    private function transformSearchOperation(Operator $operator) {
+        [, $trimmedType] = explode('}', $operator->type);
+        switch ($operator->type) {
+            case Operator::OPERATION_AND:
+            case Operator::OPERATION_OR:
+            case Operator::OPERATION_NOT:
+                $arguments = array_map([$this, 'transformSearchOperation'], $operator->arguments);
+                return new SearchBinaryOperator($trimmedType, $arguments);
+            case Operator::OPERATION_EQUAL:
+            case Operator::OPERATION_GREATER_OR_EQUAL_THAN:
+            case Operator::OPERATION_GREATER_THAN:
+            case Operator::OPERATION_LESS_OR_EQUAL_THAN:
+            case Operator::OPERATION_LESS_THAN:
+            case Operator::OPERATION_IS_LIKE:
+                if (count($operator->arguments) !== 2) {
+                    throw new \InvalidArgumentException('Invalid number of arguments for ' . $trimmedType . ' operation');
+                }
+                if (!($operator->arguments[0] instanceof SearchPropertyDefinition)) {
+                    throw new \InvalidArgumentException('Invalid argument 1 for ' . $trimmedType . ' operation, expected property');
+                }
+                if (!($operator->arguments[1] instanceof Literal)) {
+                    throw new \InvalidArgumentException('Invalid argument 2 for ' . $trimmedType . ' operation, expected literal');
+                }
+                return new SearchComparison($trimmedType, $this->mapPropertyNameToColumn($operator->arguments[0]), $this->castValue($operator->arguments[0], $operator->arguments[1]->value));
+            case Operator::OPERATION_IS_COLLECTION:
+                return new SearchComparison('eq', 'mimetype', ICacheEntry::DIRECTORY_MIMETYPE);
+            default:
+                throw new \InvalidArgumentException('Unsupported operation ' . $trimmedType . ' (' . $operator->type . ')');
+        }
+    }
+
+    /**
+     * @param SearchPropertyDefinition $property
+     * @return string
+     */
+    private function mapPropertyNameToColumn(SearchPropertyDefinition $property) {
+        switch ($property->name) {
+            case '{DAV:}displayname':
+                return 'name';
+            case '{DAV:}getcontenttype':
+                return 'mimetype';
+            case '{DAV:}getlastmodified':
+                return 'mtime';
+            case FilesPlugin::SIZE_PROPERTYNAME:
+                return 'size';
+            case TagsPlugin::FAVORITE_PROPERTYNAME:
+                return 'favorite';
+            case TagsPlugin::TAGS_PROPERTYNAME:
+                return 'tagname';
+            case FilesPlugin::INTERNAL_FILEID_PROPERTYNAME:
+                return 'fileid';
+            default:
+                throw new \InvalidArgumentException('Unsupported property for search or order: ' . $property->name);
+        }
+    }
+
+    private function castValue(SearchPropertyDefinition $property, $value) {
+        switch ($property->dataType) {
+            case SearchPropertyDefinition::DATATYPE_BOOLEAN:
+                return $value === 'yes';
+            case SearchPropertyDefinition::DATATYPE_DECIMAL:
+            case SearchPropertyDefinition::DATATYPE_INTEGER:
+            case SearchPropertyDefinition::DATATYPE_NONNEGATIVE_INTEGER:
+                return 0 + $value;
+            case SearchPropertyDefinition::DATATYPE_DATETIME:
+                if (is_numeric($value)) {
+                    return max(0, 0 + $value);
+                }
+                $date = \DateTime::createFromFormat(\DateTime::ATOM, $value);
+                return ($date instanceof \DateTime && $date->getTimestamp() !== false) ? $date->getTimestamp() : 0;
+            default:
+                return $value;
+        }
+    }
+
+    /**
+     * Get a specific property from the were clause
+     */
+    private function extractWhereValue(Operator &$operator, string $propertyName, string $comparison, bool $acceptableLocation = true): ?string {
+        switch ($operator->type) {
+            case Operator::OPERATION_AND:
+            case Operator::OPERATION_OR:
+            case Operator::OPERATION_NOT:
+                foreach ($operator->arguments as &$argument) {
+                    $value = $this->extractWhereValue($argument, $propertyName, $comparison, $acceptableLocation && $operator->type === Operator::OPERATION_AND);
+                    if ($value !== null) {
+                        return $value;
+                    }
+                }
+                return null;
+            case Operator::OPERATION_EQUAL:
+            case Operator::OPERATION_GREATER_OR_EQUAL_THAN:
+            case Operator::OPERATION_GREATER_THAN:
+            case Operator::OPERATION_LESS_OR_EQUAL_THAN:
+            case Operator::OPERATION_LESS_THAN:
+            case Operator::OPERATION_IS_LIKE:
+                if ($operator->arguments[0]->name === $propertyName) {
+                    if ($operator->type === $comparison) {
+                        if ($acceptableLocation) {
+                            if ($operator->arguments[1] instanceof Literal) {
+                                $value = $operator->arguments[1]->value;
+
+                                // to remove the comparison from the query, we replace it with an empty AND
+                                $operator = new Operator(Operator::OPERATION_AND);
+
+                                return $value;
+                            } else {
+                                throw new \InvalidArgumentException("searching by '$propertyName' is only allowed with a literal value");
+                            }
+                        } else {
+                            throw new \InvalidArgumentException("searching by '$propertyName' is not allowed inside a '{DAV:}or' or '{DAV:}not'");
+                        }
+                    } else {
+                        throw new \InvalidArgumentException("searching by '$propertyName' is only allowed inside a '$comparison'");
+                    }
+                } else {
+                    return null;
+                }
+                // no break
+            default:
+                return null;
+        }
+    }
 }