Add unified search API

Signed-off-by: Christoph Wurst <christoph@winzerhof-wurst.at>

4 files changed, 376 insertions, 0 deletions

diff --git a/lib/public/Search/ASearchResultEntry.php b/lib/public/Search/ASearchResultEntry.php
new file mode 100644
index 00000000000..45d62525abd
--- /dev/null
+++ b/lib/public/Search/ASearchResultEntry.php
@@ -0,0 +1,102 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright 2020 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @author 2020 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+
+namespace OCP\Search;
+
+use JsonSerializable;
+
+/**
+ * Represents an entry in a list of results an app returns for a unified search
+ * query.
+ *
+ * The app providing the results has to extend this class for customization. In
+ * most cases apps do not have to add any additional code.
+ *
+ * @example ``class MailResultEntry extends ASearchResultEntry {}`
+ *
+ * This approach was chosen over a final class as it allows Nextcloud to later
+ * add new optional properties of an entry without having to break the usage of
+ * this class in apps.
+ *
+ * @since 20.0.0
+ */
+abstract class ASearchResultEntry implements JsonSerializable {
+
+	/**
+	 * @var string
+	 * @since 20.0.0
+	 */
+	protected $thumbnailUrl;
+
+	/**
+	 * @var string
+	 * @since 20.0.0
+	 */
+	protected $title;
+
+	/**
+	 * @var string
+	 * @since 20.0.0
+	 */
+	protected $subline;
+
+	/**
+	 * @var string
+	 * @since 20.0.0
+	 */
+	protected $resourceUrl;
+
+	/**
+	 * @param string $thumbnailUrl a relative or absolute URL to the thumbnail or icon of the entry
+	 * @param string $title a main title of the entry
+	 * @param string $subline the secondary line of the entry
+	 * @param string $resourceUrl the URL where the user can find the detail, like a deep link inside the app
+	 *
+	 * @since 20.0.0
+	 */
+	public function __construct(string $thumbnailUrl,
+								string $title,
+								string $subline,
+								string $resourceUrl) {
+		$this->thumbnailUrl = $thumbnailUrl;
+		$this->title = $title;
+		$this->subline = $subline;
+		$this->resourceUrl = $resourceUrl;
+	}
+
+	/**
+	 * @return array
+	 *
+	 * @since 20.0.0
+	 */
+	public function jsonSerialize(): array {
+		return [
+			'thumbnailUrl' => $this->thumbnailUrl,
+			'title' => $this->title,
+			'subline' => $this->subline,
+			'resourceUrl' => $this->resourceUrl,
+		];
+	}
+}
diff --git a/lib/public/Search/IProvider.php b/lib/public/Search/IProvider.php
new file mode 100644
index 00000000000..57343eda0e5
--- /dev/null
+++ b/lib/public/Search/IProvider.php
@@ -0,0 +1,83 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright 2020 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @author 2020 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+
+namespace OCP\Search;
+
+use OCP\IUser;
+
+/**
+ * Interface for an app search providers
+ *
+ * These providers will be implemented in apps, so they can participate in the
+ * global search results of Nextcloud. If an app provides more than one type of
+ * resource, e.g. contacts and address books in Nextcloud Contacts, it should
+ * register one provider per group.
+ *
+ * @since 20.0.0
+ */
+interface IProvider {
+
+	/**
+	 * Get the unique ID of this search provider
+	 *
+	 * Ideally this should be the app name or an identifier identified with the
+	 * app name, especially if the app registers more than one provider.
+	 *
+	 * Example: 'mail', 'mail_recipients', 'files_sharing'
+	 *
+	 * @return string
+	 *
+	 * @since 20.0.0
+	 */
+	public function getId(): string;
+
+	/**
+	 * Find matching search entries in an app
+	 *
+	 * Search results can either be a complete list of all the matches the app can
+	 * find, or ideally a paginated result set where more data can be fetched on
+	 * demand. To be able to tell where the next offset starts the search uses
+	 * "cursors" which are a property of the last result entry. E.g. search results
+	 * that show most recent entries first can look for entries older than the last
+	 * one of the first result set. This approach was chosen over a numeric limit/
+	 * offset approach as the offset moves as new data comes in. The cursor is
+	 * resistant to these changes and will still show results without overlaps or
+	 * gaps.
+	 *
+	 * See https://dev.to/jackmarchant/offset-and-cursor-pagination-explained-b89
+	 * for the concept of cursors.
+	 *
+	 * Implementations that return result pages have to adhere to the limit
+	 * property of a search query.
+	 *
+	 * @param IUser $user
+	 * @param ISearchQuery $query
+	 *
+	 * @return SearchResult
+	 *
+	 * @since 20.0.0
+	 */
+	public function search(IUser $user, ISearchQuery $query): SearchResult;
+}
diff --git a/lib/public/Search/ISearchQuery.php b/lib/public/Search/ISearchQuery.php
new file mode 100644
index 00000000000..00d538050d4
--- /dev/null
+++ b/lib/public/Search/ISearchQuery.php
@@ -0,0 +1,79 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright 2020 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @author 2020 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+
+namespace OCP\Search;
+
+/**
+ * The query objected passed into \OCP\Search\IProvider::search
+ *
+ * This mainly wraps the search term, but will ensure that Nextcloud can add new
+ * optional properties to a search request without having break the interface of
+ * \OCP\Search\IProvider::search.
+ *
+ * @see \OCP\Search\IProvider::search
+ *
+ * @since 20.0.0
+ */
+interface ISearchQuery {
+
+	/**
+	 * @since 20.0.0
+	 */
+	public const SORT_DATE_DESC = 1;
+
+	/**
+	 * Get the user-entered search term to find matches for
+	 *
+	 * @return string the search term
+	 * @since 20.0.0
+	 */
+	public function getTerm(): string;
+
+	/**
+	 * Get the sort order of results as defined as SORT_* constants on this interface
+	 *
+	 * @return int
+	 * @since 20.0.0
+	 */
+	public function getSortOrder(): int;
+
+	/**
+	 * Get the number of items to return for a paginated result
+	 *
+	 * @return int
+	 * @see \OCP\Search\IProvider for details
+	 * @since 20.0.0
+	 */
+	public function getLimit(): int;
+
+	/**
+	 * Get the app-specific cursor of the tail of the previous result entries
+	 *
+	 * @return int|string|null
+	 * @see \OCP\Search\IProvider for details
+	 * @since 20.0.0
+	 */
+	public function getCursor();
+}
diff --git a/lib/public/Search/SearchResult.php b/lib/public/Search/SearchResult.php
new file mode 100644
index 00000000000..7abb5b9f188
--- /dev/null
+++ b/lib/public/Search/SearchResult.php
@@ -0,0 +1,112 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright 2020 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @author 2020 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+
+namespace OCP\Search;
+
+use JsonSerializable;
+
+/**
+ * @since 20.0.0
+ */
+final class SearchResult implements JsonSerializable {
+
+	/** @var string */
+	private $name;
+
+	/** @var bool */
+	private $isPaginated;
+
+	/** @var ASearchResultEntry[] */
+	private $entries;
+
+	/** @var int|string|null */
+	private $cursor;
+
+	/**
+	 * @param string $name the translated name of the result section or group, e.g. "Mail"
+	 * @param bool $isPaginated
+	 * @param ASearchResultEntry[] $entries
+	 * @param null $cursor
+	 *
+	 * @since 20.0.0
+	 */
+	private function __construct(string $name,
+								 bool $isPaginated,
+								 array $entries,
+								 $cursor = null) {
+		$this->name = $name;
+		$this->isPaginated = $isPaginated;
+		$this->entries = $entries;
+		$this->cursor = $cursor;
+	}
+
+	/**
+	 * @param ASearchResultEntry[] $entries
+	 *
+	 * @return static
+	 *
+	 * @since 20.0.0
+	 */
+	public static function complete(string $name, array $entries): self {
+		return new self(
+			$name,
+			false,
+			$entries
+		);
+	}
+
+	/**
+	 * @param ASearchResultEntry[] $entries
+	 * @param int|string $cursor
+	 *
+	 * @return static
+	 *
+	 * @since 20.0.0
+	 */
+	public static function paginated(string $name,
+									array $entries,
+									 $cursor): self {
+		return new self(
+			$name,
+			true,
+			$entries,
+			$cursor
+		);
+	}
+
+	/**
+	 * @return array
+	 *
+	 * @since 20.0.0
+	 */
+	public function jsonSerialize(): array {
+		return [
+			'name' => $this->name,
+			'isPaginated' => $this->isPaginated,
+			'entries' => $this->entries,
+			'cursor' => $this->cursor,
+		];
+	}
+}