Merge pull request #6328 from nextcloud/split-sharees-api-logic

Splits off the logic from sharees endpoint thus making it available from within Nc/via PHP.

10 files changed, 879 insertions, 0 deletions

diff --git a/lib/private/App/InfoParser.php b/lib/private/App/InfoParser.php
index fef8ab7a1e8..0531682d67a 100644
--- a/lib/private/App/InfoParser.php
+++ b/lib/private/App/InfoParser.php
@@ -165,6 +165,12 @@ class InfoParser {
 		if (isset($array['activity']['providers']['provider']) && is_array($array['activity']['providers']['provider'])) {
 			$array['activity']['providers'] = $array['activity']['providers']['provider'];
 		}
+		if (isset($array['collaboration']['collaborators']['searchPlugins']['searchPlugin'])
+			&& is_array($array['collaboration']['collaborators']['searchPlugins']['searchPlugin'])
+			&& !isset($array['collaboration']['collaborators']['searchPlugins']['searchPlugin']['class'])
+		) {
+			$array['collaboration']['collaborators']['searchPlugins'] = $array['collaboration']['collaborators']['searchPlugins']['searchPlugin'];
+		}
 
 		if(!is_null($this->cache)) {
 			$this->cache->set($fileCacheKey, json_encode($array));
diff --git a/lib/private/Collaboration/Collaborators/GroupPlugin.php b/lib/private/Collaboration/Collaborators/GroupPlugin.php
new file mode 100644
index 00000000000..0b2b3d71028
--- /dev/null
+++ b/lib/private/Collaboration/Collaborators/GroupPlugin.php
@@ -0,0 +1,124 @@
+<?php
+/**
+ * @copyright Copyright (c) 2017 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @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 OC\Collaboration\Collaborators;
+
+use OCP\Collaboration\Collaborators\ISearchPlugin;
+use OCP\Collaboration\Collaborators\ISearchResult;
+use OCP\Collaboration\Collaborators\SearchResultType;
+use OCP\IConfig;
+use OCP\IGroup;
+use OCP\IGroupManager;
+use OCP\IUserSession;
+use OCP\Share;
+
+class GroupPlugin implements ISearchPlugin {
+	protected $shareeEnumeration;
+	protected $shareWithGroupOnly;
+
+	/** @var IGroupManager */
+	private $groupManager;
+	/** @var IConfig */
+	private $config;
+	/** @var IUserSession */
+	private $userSession;
+
+	public function __construct(IConfig $config, IGroupManager $groupManager, IUserSession $userSession) {
+		$this->groupManager = $groupManager;
+		$this->config = $config;
+		$this->userSession = $userSession;
+
+		$this->shareeEnumeration = $this->config->getAppValue('core', 'shareapi_allow_share_dialog_user_enumeration', 'yes') === 'yes';
+		$this->shareWithGroupOnly = $this->config->getAppValue('core', 'shareapi_only_share_with_group_members', 'no') === 'yes';
+	}
+
+	public function search($search, $limit, $offset, ISearchResult $searchResult) {
+		$hasMoreResults = false;
+		$result = ['wide' => [], 'exact' => []];
+
+		$groups = $this->groupManager->search($search, $limit, $offset);
+		$groupIds = array_map(function (IGroup $group) { return $group->getGID(); }, $groups);
+
+		if (!$this->shareeEnumeration || sizeof($groups) < $limit) {
+			$hasMoreResults = true;
+		}
+
+		$userGroups =  [];
+		if (!empty($groups) && $this->shareWithGroupOnly) {
+			// Intersect all the groups that match with the groups this user is a member of
+			$userGroups = $this->groupManager->getUserGroups($this->userSession->getUser());
+			$userGroups = array_map(function (IGroup $group) { return $group->getGID(); }, $userGroups);
+			$groupIds = array_intersect($groupIds, $userGroups);
+		}
+
+		$lowerSearch = strtolower($search);
+		foreach ($groups as $group) {
+			// FIXME: use a more efficient approach
+			$gid = $group->getGID();
+			if (!in_array($gid, $groupIds)) {
+				continue;
+			}
+			if (strtolower($gid) === $lowerSearch || strtolower($group->getDisplayName()) === $lowerSearch) {
+				$result['exact'][] = [
+					'label' => $group->getDisplayName(),
+					'value' => [
+						'shareType' => Share::SHARE_TYPE_GROUP,
+						'shareWith' => $gid,
+					],
+				];
+			} else {
+				$result['wide'][] = [
+					'label' => $group->getDisplayName(),
+					'value' => [
+						'shareType' => Share::SHARE_TYPE_GROUP,
+						'shareWith' => $gid,
+					],
+				];
+			}
+		}
+
+		if ($offset === 0 && empty($result['exact'])) {
+			// On page one we try if the search result has a direct hit on the
+			// user id and if so, we add that to the exact match list
+			$group = $this->groupManager->get($search);
+			if ($group instanceof IGroup && (!$this->shareWithGroupOnly || in_array($group->getGID(), $userGroups))) {
+				array_push($result['exact'], [
+					'label' => $group->getDisplayName(),
+					'value' => [
+						'shareType' => Share::SHARE_TYPE_GROUP,
+						'shareWith' => $group->getGID(),
+					],
+				]);
+			}
+		}
+
+		if (!$this->shareeEnumeration) {
+			$result['wide'] = [];
+		}
+
+		$type = new SearchResultType('groups');
+		$searchResult->addResultSet($type, $result['wide'], $result['exact']);
+
+		return $hasMoreResults;
+	}
+}
diff --git a/lib/private/Collaboration/Collaborators/LookupPlugin.php b/lib/private/Collaboration/Collaborators/LookupPlugin.php
new file mode 100644
index 00000000000..3a6a0943772
--- /dev/null
+++ b/lib/private/Collaboration/Collaborators/LookupPlugin.php
@@ -0,0 +1,85 @@
+<?php
+/**
+ * @copyright Copyright (c) 2017 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @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 OC\Collaboration\Collaborators;
+
+
+use OCP\Collaboration\Collaborators\ISearchPlugin;
+use OCP\Collaboration\Collaborators\ISearchResult;
+use OCP\Collaboration\Collaborators\SearchResultType;
+use OCP\Http\Client\IClientService;
+use OCP\IConfig;
+use OCP\Share;
+
+class LookupPlugin implements ISearchPlugin {
+
+	/** @var IConfig */
+	private $config;
+	/** @var IClientService */
+	private $clientService;
+
+	public function __construct(IConfig $config, IClientService $clientService) {
+		$this->config = $config;
+		$this->clientService = $clientService;
+	}
+
+	public function search($search, $limit, $offset, ISearchResult $searchResult) {
+		if ($this->config->getAppValue('files_sharing', 'lookupServerEnabled', 'no') !== 'yes') {
+			return false;
+		}
+
+		$lookupServerUrl = $this->config->getSystemValue('lookup_server', 'https://lookup.nextcloud.com');
+		$lookupServerUrl = rtrim($lookupServerUrl, '/');
+		$result = [];
+
+		try {
+			$client = $this->clientService->newClient();
+			$response = $client->get(
+				$lookupServerUrl . '/users?search=' . urlencode($search),
+				[
+					'timeout' => 10,
+					'connect_timeout' => 3,
+				]
+			);
+
+			$body = json_decode($response->getBody(), true);
+
+			foreach ($body as $lookup) {
+				$result[] = [
+					'label' => $lookup['federationId'],
+					'value' => [
+						'shareType' => Share::SHARE_TYPE_REMOTE,
+						'shareWith' => $lookup['federationId'],
+					],
+					'extra' => $lookup,
+				];
+			}
+		} catch (\Exception $e) {
+		}
+
+		$type = new SearchResultType('lookup');
+		$searchResult->addResultSet($type, $result, []);
+
+		return false;
+	}
+}
diff --git a/lib/private/Collaboration/Collaborators/MailPlugin.php b/lib/private/Collaboration/Collaborators/MailPlugin.php
new file mode 100644
index 00000000000..d28bd3692a4
--- /dev/null
+++ b/lib/private/Collaboration/Collaborators/MailPlugin.php
@@ -0,0 +1,164 @@
+<?php
+/**
+ * @copyright Copyright (c) 2017 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @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 OC\Collaboration\Collaborators;
+
+
+use OCP\Collaboration\Collaborators\ISearchPlugin;
+use OCP\Collaboration\Collaborators\ISearchResult;
+use OCP\Collaboration\Collaborators\SearchResultType;
+use OCP\Contacts\IManager;
+use OCP\Federation\ICloudIdManager;
+use OCP\IConfig;
+use OCP\Share;
+
+class MailPlugin implements ISearchPlugin {
+	protected $shareeEnumeration;
+
+	/** @var IManager */
+	private $contactsManager;
+	/** @var ICloudIdManager */
+	private $cloudIdManager;
+	/** @var IConfig */
+	private $config;
+
+	public function __construct(IManager $contactsManager, ICloudIdManager $cloudIdManager, IConfig $config) {
+		$this->contactsManager = $contactsManager;
+		$this->cloudIdManager = $cloudIdManager;
+		$this->config = $config;
+
+		$this->shareeEnumeration = $this->config->getAppValue('core', 'shareapi_allow_share_dialog_user_enumeration', 'yes') === 'yes';
+	}
+
+	/**
+	 * @param $search
+	 * @param $limit
+	 * @param $offset
+	 * @param ISearchResult $searchResult
+	 * @return bool
+	 * @since 13.0.0
+	 */
+	public function search($search, $limit, $offset, ISearchResult $searchResult) {
+		$result = ['wide' => [], 'exact' => []];
+		$userType = new SearchResultType('users');
+		$emailType = new SearchResultType('emails');
+
+		// Search in contacts
+		//@todo Pagination missing
+		$addressBookContacts = $this->contactsManager->search($search, ['EMAIL', 'FN']);
+		$lowerSearch = strtolower($search);
+		foreach ($addressBookContacts as $contact) {
+			if (isset($contact['EMAIL'])) {
+				$emailAddresses = $contact['EMAIL'];
+				if (!is_array($emailAddresses)) {
+					$emailAddresses = [$emailAddresses];
+				}
+				foreach ($emailAddresses as $emailAddress) {
+					$exactEmailMatch = strtolower($emailAddress) === $lowerSearch;
+
+					if (isset($contact['isLocalSystemBook'])) {
+						if ($exactEmailMatch) {
+							try {
+								$cloud = $this->cloudIdManager->resolveCloudId($contact['CLOUD'][0]);
+							} catch (\InvalidArgumentException $e) {
+								continue;
+							}
+
+							if (!$searchResult->hasResult($userType, $cloud->getUser())) {
+								$singleResult = [[
+									'label' => $contact['FN'] . " ($emailAddress)",
+									'value' => [
+										'shareType' => Share::SHARE_TYPE_USER,
+										'shareWith' => $cloud->getUser(),
+									],
+								]];
+								$searchResult->addResultSet($userType, [], $singleResult);
+								$searchResult->markExactIdMatch($emailType);
+							}
+							return false;
+						}
+
+						if ($this->shareeEnumeration) {
+							try {
+								$cloud = $this->cloudIdManager->resolveCloudId($contact['CLOUD'][0]);
+							} catch (\InvalidArgumentException $e) {
+								continue;
+							}
+
+							if (!$searchResult->hasResult($userType, $cloud->getUser())) {
+								$singleResult = [[
+									'label' => $contact['FN'] . " ($emailAddress)",
+									'value' => [
+										'shareType' => Share::SHARE_TYPE_USER,
+										'shareWith' => $cloud->getUser(),
+									]],
+								];
+								$searchResult->addResultSet($userType, $singleResult, []);
+							}
+						}
+						continue;
+					}
+
+					if ($exactEmailMatch || strtolower($contact['FN']) === $lowerSearch) {
+						if ($exactEmailMatch) {
+							$searchResult->markExactIdMatch($emailType);
+						}
+						$result['exact'][] = [
+							'label' => $contact['FN'] . " ($emailAddress)",
+							'value' => [
+								'shareType' => Share::SHARE_TYPE_EMAIL,
+								'shareWith' => $emailAddress,
+							],
+						];
+					} else {
+						$result['wide'][] = [
+							'label' => $contact['FN'] . " ($emailAddress)",
+							'value' => [
+								'shareType' => Share::SHARE_TYPE_EMAIL,
+								'shareWith' => $emailAddress,
+							],
+						];
+					}
+				}
+			}
+		}
+
+		if (!$this->shareeEnumeration) {
+			$result['wide'] = [];
+		}
+
+		if (!$searchResult->hasExactIdMatch($emailType) && filter_var($search, FILTER_VALIDATE_EMAIL)) {
+			$result['exact'][] = [
+				'label' => $search,
+				'value' => [
+					'shareType' => Share::SHARE_TYPE_EMAIL,
+					'shareWith' => $search,
+				],
+			];
+		}
+
+		$searchResult->addResultSet($emailType, $result['wide'], $result['exact']);
+
+		return true;
+	}
+}
diff --git a/lib/private/Collaboration/Collaborators/RemotePlugin.php b/lib/private/Collaboration/Collaborators/RemotePlugin.php
new file mode 100644
index 00000000000..b17a64e4ff1
--- /dev/null
+++ b/lib/private/Collaboration/Collaborators/RemotePlugin.php
@@ -0,0 +1,137 @@
+<?php
+/**
+ * @copyright Copyright (c) 2017 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @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 OC\Collaboration\Collaborators;
+
+
+use OCP\Collaboration\Collaborators\ISearchPlugin;
+use OCP\Collaboration\Collaborators\ISearchResult;
+use OCP\Collaboration\Collaborators\SearchResultType;
+use OCP\Contacts\IManager;
+use OCP\Federation\ICloudIdManager;
+use OCP\IConfig;
+use OCP\Share;
+
+class RemotePlugin implements ISearchPlugin {
+	protected $shareeEnumeration;
+
+	/** @var IManager */
+	private $contactsManager;
+	/** @var ICloudIdManager */
+	private $cloudIdManager;
+	/** @var IConfig */
+	private $config;
+
+	public function __construct(IManager $contactsManager, ICloudIdManager $cloudIdManager, IConfig $config) {
+		$this->contactsManager = $contactsManager;
+		$this->cloudIdManager = $cloudIdManager;
+		$this->config = $config;
+
+		$this->shareeEnumeration = $this->config->getAppValue('core', 'shareapi_allow_share_dialog_user_enumeration', 'yes') === 'yes';
+	}
+
+	public function search($search, $limit, $offset, ISearchResult $searchResult) {
+		$result = ['wide' => [], 'exact' => []];
+		$resultType = new SearchResultType('remotes');
+
+		// Search in contacts
+		//@todo Pagination missing
+		$addressBookContacts = $this->contactsManager->search($search, ['CLOUD', 'FN']);
+		foreach ($addressBookContacts as $contact) {
+			if (isset($contact['isLocalSystemBook'])) {
+				continue;
+			}
+			if (isset($contact['CLOUD'])) {
+				$cloudIds = $contact['CLOUD'];
+				if (!is_array($cloudIds)) {
+					$cloudIds = [$cloudIds];
+				}
+				$lowerSearch = strtolower($search);
+				foreach ($cloudIds as $cloudId) {
+					try {
+						list(, $serverUrl) = $this->splitUserRemote($cloudId);
+					} catch (\InvalidArgumentException $e) {
+						continue;
+					}
+
+					if (strtolower($contact['FN']) === $lowerSearch || strtolower($cloudId) === $lowerSearch) {
+						if (strtolower($cloudId) === $lowerSearch) {
+							$searchResult->markExactIdMatch($resultType);
+						}
+						$result['exact'][] = [
+							'label' => $contact['FN'] . " ($cloudId)",
+							'value' => [
+								'shareType' => Share::SHARE_TYPE_REMOTE,
+								'shareWith' => $cloudId,
+								'server' => $serverUrl,
+							],
+						];
+					} else {
+						$result['wide'][] = [
+							'label' => $contact['FN'] . " ($cloudId)",
+							'value' => [
+								'shareType' => Share::SHARE_TYPE_REMOTE,
+								'shareWith' => $cloudId,
+								'server' => $serverUrl,
+							],
+						];
+					}
+				}
+			}
+		}
+
+		if (!$this->shareeEnumeration) {
+			$result['wide'] = [];
+		}
+
+		if (!$searchResult->hasExactIdMatch($resultType) && $this->cloudIdManager->isValidCloudId($search) && $offset === 0) {
+			$result['exact'][] = [
+				'label' => $search,
+				'value' => [
+					'shareType' => Share::SHARE_TYPE_REMOTE,
+					'shareWith' => $search,
+				],
+			];
+		}
+
+		$searchResult->addResultSet($resultType, $result['wide'], $result['exact']);
+
+		return true;
+	}
+
+	/**
+	 * split user and remote from federated cloud id
+	 *
+	 * @param string $address federated share address
+	 * @return array [user, remoteURL]
+	 * @throws \InvalidArgumentException
+	 */
+	public function splitUserRemote($address) {
+		try {
+			$cloudId = $this->cloudIdManager->resolveCloudId($address);
+			return [$cloudId->getUser(), $cloudId->getRemote()];
+		} catch (\InvalidArgumentException $e) {
+			throw new \InvalidArgumentException('Invalid Federated Cloud ID', 0, $e);
+		}
+	}
+}
diff --git a/lib/private/Collaboration/Collaborators/Search.php b/lib/private/Collaboration/Collaborators/Search.php
new file mode 100644
index 00000000000..e9b15dd1201
--- /dev/null
+++ b/lib/private/Collaboration/Collaborators/Search.php
@@ -0,0 +1,89 @@
+<?php
+/**
+ * @copyright Copyright (c) 2017 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @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 OC\Collaboration\Collaborators;
+
+use OCP\Collaboration\Collaborators\ISearch;
+use OCP\Collaboration\Collaborators\ISearchPlugin;
+use OCP\Collaboration\Collaborators\ISearchResult;
+use OCP\Collaboration\Collaborators\SearchResultType;
+use OCP\IContainer;
+use OCP\Share;
+
+class Search implements ISearch {
+	/** @var IContainer */
+	private $c;
+
+	protected $pluginList = [];
+
+	public function __construct(IContainer $c) {
+		$this->c = $c;
+	}
+
+	public function search($search, array $shareTypes, $lookup, $limit, $offset) {
+		$hasMoreResults = false;
+
+		/** @var ISearchResult $searchResult */
+		$searchResult = $this->c->resolve(SearchResult::class);
+
+		foreach ($shareTypes as $type) {
+			if(!isset($this->pluginList[$type])) {
+				continue;
+			}
+			foreach ($this->pluginList[$type] as $plugin) {
+				/** @var ISearchPlugin $searchPlugin */
+				$searchPlugin = $this->c->resolve($plugin);
+				$hasMoreResults |= $searchPlugin->search($search, $limit, $offset, $searchResult);
+			}
+		}
+
+		// Get from lookup server, not a separate share type
+		if ($lookup) {
+			$searchPlugin = $this->c->resolve(LookupPlugin::class);
+			$hasMoreResults |= $searchPlugin->search($search, $limit, $offset, $searchResult);
+		}
+
+		// sanitizing, could go into the plugins as well
+
+		// if we have a exact match, either for the federated cloud id or for the
+		// email address we only return the exact match. It is highly unlikely
+		// that the exact same email address and federated cloud id exists
+		$emailType = new SearchResultType('emails');
+		$remoteType = new SearchResultType('remotes');
+		if($searchResult->hasExactIdMatch($emailType) && !$searchResult->hasExactIdMatch($remoteType)) {
+			$searchResult->unsetResult($remoteType);
+		} elseif (!$searchResult->hasExactIdMatch($emailType) && $searchResult->hasExactIdMatch($remoteType)) {
+			$searchResult->unsetResult($emailType);
+		}
+
+		return [$searchResult->asArray(), (bool)$hasMoreResults];
+	}
+
+	public function registerPlugin(array $pluginInfo) {
+		$shareType = constant(Share::class . '::' . $pluginInfo['shareType']);
+		if($shareType === null) {
+			throw new \InvalidArgumentException('Provided ShareType is invalid');
+		}
+		$this->pluginList[$shareType][] = $pluginInfo['class'];
+	}
+}
diff --git a/lib/private/Collaboration/Collaborators/SearchResult.php b/lib/private/Collaboration/Collaborators/SearchResult.php
new file mode 100644
index 00000000000..7b32b388203
--- /dev/null
+++ b/lib/private/Collaboration/Collaborators/SearchResult.php
@@ -0,0 +1,86 @@
+<?php
+/**
+ * @copyright Copyright (c) 2017 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @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 OC\Collaboration\Collaborators;
+
+
+use OCP\Collaboration\Collaborators\ISearchResult;
+use OCP\Collaboration\Collaborators\SearchResultType;
+
+class SearchResult implements ISearchResult {
+
+	protected $result = [
+		'exact' => [],
+	];
+
+	protected $exactIdMatches = [];
+
+	public function addResultSet(SearchResultType $type, array $matches, array $exactMatches = null) {
+		$type = $type->getLabel();
+		if(!isset($this->result[$type])) {
+			$this->result[$type] = [];
+			$this->result['exact'][$type] = [];
+		}
+
+		$this->result[$type] = array_merge($this->result[$type], $matches);
+		if(is_array($exactMatches)) {
+			$this->result['exact'][$type] = array_merge($this->result['exact'][$type], $exactMatches);
+		}
+	}
+
+	public function markExactIdMatch(SearchResultType $type) {
+		$this->exactIdMatches[$type->getLabel()] = 1;
+	}
+
+	public function hasExactIdMatch(SearchResultType$type) {
+		return isset($this->exactIdMatches[$type->getLabel()]);
+	}
+
+	public function hasResult(SearchResultType $type, $collaboratorId) {
+		$type = $type->getLabel();
+		if(!isset($this->result[$type])) {
+			return false;
+		}
+
+		$resultArrays = [$this->result['exact'][$type], $this->result[$type]];
+		foreach($resultArrays as $resultArray) {
+			if ($resultArray['value']['shareWith'] === $collaboratorId) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	public function asArray() {
+		return $this->result;
+	}
+
+	public function unsetResult(SearchResultType $type) {
+		$type = $type->getLabel();
+		$this->result[$type] = [];
+		if(isset($this->result['exact'][$type])) {
+			$this->result['exact'][$type] = [];
+		}
+	}
+}
diff --git a/lib/private/Collaboration/Collaborators/UserPlugin.php b/lib/private/Collaboration/Collaborators/UserPlugin.php
new file mode 100644
index 00000000000..86a55aa428f
--- /dev/null
+++ b/lib/private/Collaboration/Collaborators/UserPlugin.php
@@ -0,0 +1,149 @@
+<?php
+/**
+ * @copyright Copyright (c) 2017 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @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 OC\Collaboration\Collaborators;
+
+
+use OCP\Collaboration\Collaborators\ISearchPlugin;
+use OCP\Collaboration\Collaborators\ISearchResult;
+use OCP\Collaboration\Collaborators\SearchResultType;
+use OCP\IConfig;
+use OCP\IGroupManager;
+use OCP\IUser;
+use OCP\IUserManager;
+use OCP\IUserSession;
+use OCP\Share;
+
+class UserPlugin implements ISearchPlugin {
+	/* @var bool */
+	protected $shareWithGroupOnly;
+	protected $shareeEnumeration;
+
+	/** @var IConfig */
+	private $config;
+	/** @var IGroupManager */
+	private $groupManager;
+	/** @var IUserSession */
+	private $userSession;
+	/** @var IUserManager */
+	private $userManager;
+
+	public function __construct(IConfig $config, IUserManager $userManager, IGroupManager $groupManager, IUserSession $userSession) {
+		$this->config = $config;
+
+		$this->groupManager = $groupManager;
+		$this->userSession = $userSession;
+		$this->userManager = $userManager;
+
+		$this->shareWithGroupOnly = $this->config->getAppValue('core', 'shareapi_only_share_with_group_members', 'no') === 'yes';
+		$this->shareeEnumeration = $this->config->getAppValue('core', 'shareapi_allow_share_dialog_user_enumeration', 'yes') === 'yes';
+	}
+
+	public function search($search, $limit, $offset, ISearchResult $searchResult) {
+		$result = ['wide' => [], 'exact' => []];
+		$users = [];
+		$hasMoreResults = false;
+
+		$userGroups = [];
+		if ($this->shareWithGroupOnly) {
+			// Search in all the groups this user is part of
+			$userGroups = $this->groupManager->getUserGroupIds($this->userSession->getUser());
+			foreach ($userGroups as $userGroup) {
+				$usersTmp = $this->groupManager->displayNamesInGroup($userGroup, $search, $limit, $offset);
+				foreach ($usersTmp as $uid => $userDisplayName) {
+					$users[$uid] = $userDisplayName;
+				}
+			}
+		} else {
+			// Search in all users
+			$usersTmp = $this->userManager->searchDisplayName($search, $limit, $offset);
+
+			foreach ($usersTmp as $user) {
+				$users[$user->getUID()] = $user->getDisplayName();
+			}
+		}
+
+		if (!$this->shareeEnumeration || sizeof($users) < $limit) {
+			$hasMoreResults = true;
+		}
+
+		$foundUserById = false;
+		$lowerSearch = strtolower($search);
+		foreach ($users as $uid => $userDisplayName) {
+			if (strtolower($uid) === $lowerSearch || strtolower($userDisplayName) === $lowerSearch) {
+				if (strtolower($uid) === $lowerSearch) {
+					$foundUserById = true;
+				}
+				$result['exact'][] = [
+					'label' => $userDisplayName,
+					'value' => [
+						'shareType' => Share::SHARE_TYPE_USER,
+						'shareWith' => $uid,
+					],
+				];
+			} else {
+				$result['wide'][] = [
+					'label' => $userDisplayName,
+					'value' => [
+						'shareType' => Share::SHARE_TYPE_USER,
+						'shareWith' => $uid,
+					],
+				];
+			}
+		}
+
+		if ($offset === 0 && !$foundUserById) {
+			// On page one we try if the search result has a direct hit on the
+			// user id and if so, we add that to the exact match list
+			$user = $this->userManager->get($search);
+			if ($user instanceof IUser) {
+				$addUser = true;
+
+				if ($this->shareWithGroupOnly) {
+					// Only add, if we have a common group
+					$commonGroups = array_intersect($userGroups, $this->groupManager->getUserGroupIds($user));
+					$addUser = !empty($commonGroups);
+				}
+
+				if ($addUser) {
+					array_push($result['exact'], [
+						'label' => $user->getDisplayName(),
+						'value' => [
+							'shareType' => Share::SHARE_TYPE_USER,
+							'shareWith' => $user->getUID(),
+						],
+					]);
+				}
+			}
+		}
+
+		if (!$this->shareeEnumeration) {
+			$result['wide'] = [];
+		}
+
+		$type = new SearchResultType('users');
+		$searchResult->addResultSet($type, $result['wide'], $result['exact']);
+
+		return $hasMoreResults;
+	}
+}
diff --git a/lib/private/Server.php b/lib/private/Server.php
index a20d9ccfc01..29aee06d896 100644
--- a/lib/private/Server.php
+++ b/lib/private/Server.php
@@ -52,6 +52,10 @@ use OC\AppFramework\Http\Request;
 use OC\AppFramework\Utility\SimpleContainer;
 use OC\AppFramework\Utility\TimeFactory;
 use OC\Authentication\LoginCredentials\Store;
+use OC\Collaboration\Collaborators\GroupPlugin;
+use OC\Collaboration\Collaborators\MailPlugin;
+use OC\Collaboration\Collaborators\RemotePlugin;
+use OC\Collaboration\Collaborators\UserPlugin;
 use OC\Command\CronBus;
 use OC\Contacts\ContactsMenu\ActionFactory;
 use OC\Diagnostics\EventLogger;
@@ -115,6 +119,7 @@ use OCP\Contacts\ContactsMenu\IActionFactory;
 use OCP\Lock\ILockingProvider;
 use OCP\RichObjectStrings\IValidator;
 use OCP\Security\IContentSecurityPolicyManager;
+use OCP\Share;
 use OCP\Share\IShareHelper;
 use Symfony\Component\EventDispatcher\EventDispatcher;
 use Symfony\Component\EventDispatcher\EventDispatcherInterface;
@@ -993,6 +998,19 @@ class Server extends ServerContainer implements IServerContainer {
 		});
 		$this->registerAlias('ShareManager', \OCP\Share\IManager::class);
 
+		$this->registerService(\OCP\Collaboration\Collaborators\ISearch::class, function(Server $c) {
+			$instance = new Collaboration\Collaborators\Search($c);
+
+			// register default plugins
+			$instance->registerPlugin(['shareType' => 'SHARE_TYPE_USER', 'class' => UserPlugin::class]);
+			$instance->registerPlugin(['shareType' => 'SHARE_TYPE_GROUP', 'class' => GroupPlugin::class]);
+			$instance->registerPlugin(['shareType' => 'SHARE_TYPE_EMAIL', 'class' => MailPlugin::class]);
+			$instance->registerPlugin(['shareType' => 'SHARE_TYPE_REMOTE', 'class' => RemotePlugin::class]);
+
+			return $instance;
+		});
+		$this->registerAlias('CollaboratorSearch', \OCP\Collaboration\Collaborators\ISearch::class);
+
 		$this->registerService('SettingsManager', function (Server $c) {
 			$manager = new \OC\Settings\Manager(
 				$c->getLogger(),
@@ -1777,6 +1795,13 @@ class Server extends ServerContainer implements IServerContainer {
 	}
 
 	/**
+	 * @return \OCP\Collaboration\Collaborators\ISearch
+	 */
+	public function getCollaboratorSearch() {
+		return $this->query('CollaboratorSearch');
+	}
+
+	/**
 	 * Returns the LDAP Provider
 	 *
 	 * @return \OCP\LDAP\ILDAPProvider
diff --git a/lib/private/legacy/app.php b/lib/private/legacy/app.php
index 24c7a344e00..a33c9be20fc 100644
--- a/lib/private/legacy/app.php
+++ b/lib/private/legacy/app.php
@@ -174,6 +174,20 @@ class OC_App {
 				\OC::$server->getActivityManager()->registerProvider($provider);
 			}
 		}
+		if (!empty($info['collaboration']['plugins'])) {
+			// deal with one or many plugin entries
+			$plugins = isset($info['collaboration']['plugins']['plugin']['@value']) ?
+				[$info['collaboration']['plugins']['plugin']] : $info['collaboration']['plugins']['plugin'];
+			foreach ($plugins as $plugin) {
+				if($plugin['@attributes']['type'] === 'collaborator-search') {
+					$pluginInfo = [
+						'shareType' => $plugin['@attributes']['share-type'],
+						'class' => $plugin['@value'],
+					];
+					\OC::$server->getCollaboratorSearch()->registerPlugin($pluginInfo);
+				}
+			}
+		}
 	}
 
 	/**