Update wiki links to the new short URL

[aur.git] / web / lib / aurjson.class.php

<?php

include_once("aur.inc.php");
include_once("pkgfuncs.inc.php");

/*
 * This class defines a remote interface for fetching data from the AUR using
 * JSON formatted elements.
 *
 * @package rpc
 * @subpackage classes
 */
class AurJSON {
        private $dbh = false;
        private $version = 1;
        private static $exposed_methods = array(
                'search', 'info', 'multiinfo', 'msearch', 'suggest',
                'suggest-pkgbase', 'get-comment-form'
        );
        private static $exposed_fields = array(
                'name', 'name-desc', 'maintainer',
                'depends', 'makedepends', 'checkdepends', 'optdepends'
        );
        private static $exposed_depfields = array(
                'depends', 'makedepends', 'checkdepends', 'optdepends'
        );
        private static $fields_v1 = array(
                'Packages.ID', 'Packages.Name',
                'PackageBases.ID AS PackageBaseID',
                'PackageBases.Name AS PackageBase', 'Version',
                'Description', 'URL', 'NumVotes', 'OutOfDateTS AS OutOfDate',
                'Users.UserName AS Maintainer',
                'SubmittedTS AS FirstSubmitted', 'ModifiedTS AS LastModified',
                'Licenses.Name AS License'
        );
        private static $fields_v2 = array(
                'Packages.ID', 'Packages.Name',
                'PackageBases.ID AS PackageBaseID',
                'PackageBases.Name AS PackageBase', 'Version',
                'Description', 'URL', 'NumVotes', 'OutOfDateTS AS OutOfDate',
                'Users.UserName AS Maintainer',
                'SubmittedTS AS FirstSubmitted', 'ModifiedTS AS LastModified'
        );
        private static $fields_v4 = array(
                'Packages.ID', 'Packages.Name',
                'PackageBases.ID AS PackageBaseID',
                'PackageBases.Name AS PackageBase', 'Version',
                'Description', 'URL', 'NumVotes', 'Popularity',
                'OutOfDateTS AS OutOfDate', 'Users.UserName AS Maintainer',
                'SubmittedTS AS FirstSubmitted', 'ModifiedTS AS LastModified'
        );
        private static $numeric_fields = array(
                'ID', 'PackageBaseID', 'NumVotes', 'OutOfDate',
                'FirstSubmitted', 'LastModified'
        );
        private static $decimal_fields = array(
                'Popularity'
        );

        /*
         * Handles post data, and routes the request.
         *
         * @param string $post_data The post data to parse and handle.
         *
         * @return string The JSON formatted response data.
         */
        public function handle($http_data) {
                /*
                 * Unset global aur.inc.php Pragma header. We want to allow
                 * caching of data in proxies, but require validation of data
                 * (if-none-match) if possible.
                 */
                header_remove('Pragma');
                /*
                 * Overwrite cache-control header set in aur.inc.php to allow
                 * caching, but require validation.
                 */
                header('Cache-Control: public, must-revalidate, max-age=0');
                header('Content-Type: application/json, charset=utf-8');

                if (isset($http_data['v'])) {
                        $this->version = intval($http_data['v']);
                }
                if ($this->version < 1 || $this->version > 6) {
                        return $this->json_error('Invalid version specified.');
                }

                if (!isset($http_data['type']) || !isset($http_data['arg'])) {
                        return $this->json_error('No request type/data specified.');
                }
                if (!in_array($http_data['type'], self::$exposed_methods)) {
                        return $this->json_error('Incorrect request type specified.');
                }

                if (isset($http_data['search_by']) && !isset($http_data['by'])) {
                        $http_data['by'] = $http_data['search_by'];
                }
                if (isset($http_data['by']) && !in_array($http_data['by'], self::$exposed_fields)) {
                        return $this->json_error('Incorrect by field specified.');
                }

                $this->dbh = DB::connect();

                if ($this->check_ratelimit($_SERVER['REMOTE_ADDR'])) {
                        header("HTTP/1.1 429 Too Many Requests");
                        return $this->json_error('Rate limit reached');
                }

                $type = str_replace('-', '_', $http_data['type']);
                if ($type == 'info' && $this->version >= 5) {
                        $type = 'multiinfo';
                }
                $json = call_user_func(array(&$this, $type), $http_data);

                $etag = md5($json);
                header("Etag: \"$etag\"");
                /*
                 * Make sure to strip a few things off the
                 * if-none-match header. Stripping whitespace may not
                 * be required, but removing the quote on the incoming
                 * header is required to make the equality test.
                 */
                $if_none_match = isset($_SERVER['HTTP_IF_NONE_MATCH']) ?
                        trim($_SERVER['HTTP_IF_NONE_MATCH'], "\t\n\r\" ") : false;
                if ($if_none_match && $if_none_match == $etag) {
                        header('HTTP/1.1 304 Not Modified');
                        return;
                }

                if (isset($http_data['callback'])) {
                        $callback = $http_data['callback'];
                        if (!preg_match('/^[a-zA-Z0-9()_.]{1,128}$/D', $callback)) {
                                return $this->json_error('Invalid callback name.');
                        }
                        header('content-type: text/javascript');
                        return '/**/' . $callback . '(' . $json . ')';
                } else {
                        header('content-type: application/json');
                        return $json;
                }
        }

        /*
         * Check if an IP needs to be rate limited.
         *
         * @param $ip IP of the current request
         *
         * @return true if IP needs to be rate limited, false otherwise.
         */
        private function check_ratelimit($ip) {
                $limit = config_get("ratelimit", "request_limit");
                if ($limit == 0) {
                        return false;
                }

                $this->update_ratelimit($ip);

                $status = false;
                $value = get_cache_value('ratelimit:' . $ip, $status);
                if (!$status) {
                        $stmt = $this->dbh->prepare("
                                SELECT Requests FROM ApiRateLimit
                                WHERE IP = :ip");
                        $stmt->bindParam(":ip", $ip);
                        $result = $stmt->execute();

                        if (!$result) {
                                return false;
                        }

                        $row = $stmt->fetch(PDO::FETCH_ASSOC);
                        $value = $row['Requests'];
                }

                return $value > $limit;
        }

        /*
         * Update a rate limit for an IP by increasing it's requests value by one.
         *
         * @param $ip IP of the current request
         *
         * @return void
         */
        private function update_ratelimit($ip) {
                $window_length = config_get("ratelimit", "window_length");
                $db_backend = config_get("database", "backend");
                $time = time();
                $deletion_time = $time - $window_length;

                /* Try to use the cache. */
                $status = false;
                $value = get_cache_value('ratelimit-ws:' . $ip, $status);
                if (!$status || ($status && $value < $deletion_time)) {
                        if (set_cache_value('ratelimit-ws:' . $ip, $time, $window_length) &&
                                set_cache_value('ratelimit:' . $ip, 1, $window_length)) {
                                return;
                        }
                } else {
                        $value = get_cache_value('ratelimit:' . $ip, $status);
                        if ($status && set_cache_value('ratelimit:' . $ip, $value + 1, $window_length))
                                return;
                }

                /* Clean up old windows. */
                $stmt = $this->dbh->prepare("
                        DELETE FROM ApiRateLimit
                        WHERE WindowStart < :time");
                $stmt->bindParam(":time", $deletion_time);
                $stmt->execute();

                if ($db_backend == "mysql") {
                        $stmt = $this->dbh->prepare("
                                INSERT INTO ApiRateLimit
                                (IP, Requests, WindowStart)
                                VALUES (:ip, 1, :window_start)
                                ON DUPLICATE KEY UPDATE Requests=Requests+1");
                        $stmt->bindParam(":ip", $ip);
                        $stmt->bindParam(":window_start", $time);
                        $stmt->execute();
                } elseif ($db_backend == "sqlite") {
                        $stmt = $this->dbh->prepare("
                                INSERT OR IGNORE INTO ApiRateLimit
                                (IP, Requests, WindowStart)
                                VALUES (:ip, 0, :window_start);");
                        $stmt->bindParam(":ip", $ip);
                        $stmt->bindParam(":window_start", $time);
                        $stmt->execute();

                        $stmt = $this->dbh->prepare("
                                UPDATE ApiRateLimit
                                SET Requests = Requests + 1
                                WHERE IP = :ip");
                        $stmt->bindParam(":ip", $ip);
                        $stmt->execute();
                } else {
                        throw new RuntimeException("Unknown database backend");
                }
        }

        /*
         * Returns a JSON formatted error string.
         *
         * @param $msg The error string to return
         *
         * @return mixed A json formatted error response.
         */
        private function json_error($msg) {
                header('content-type: application/json');
                if ($this->version < 3) {
                        return $this->json_results('error', 0, $msg, NULL);
                } elseif ($this->version >= 3) {
                        return $this->json_results('error', 0, array(), $msg);
                }
        }

        /*
         * Returns a JSON formatted result data.
         *
         * @param $type The response method type.
         * @param $count The number of results to return
         * @param $data The result data to return
         * @param $error An error message to include in the response
         *
         * @return mixed A json formatted result response.
         */
        private function json_results($type, $count, $data, $error) {
                $json_array = array(
                        'version' => $this->version,
                        'type' => $type,
                        'resultcount' => $count,
                        'results' => $data
                );

                if ($error) {
                        $json_array['error'] = $error;
                }

                return json_encode($json_array);
        }

        /*
         * Get extended package details (for info and multiinfo queries).
         *
         * @param $pkgid The ID of the package to retrieve details for.
         * @param $base_id The ID of the package base to retrieve details for.
         *
         * @return array An array containing package details.
         */
        private function get_extended_fields($pkgid, $base_id) {
                $query = "SELECT DependencyTypes.Name AS Type, " .
                        "PackageDepends.DepName AS Name, " .
                        "PackageDepends.DepCondition AS Cond " .
                        "FROM PackageDepends " .
                        "LEFT JOIN DependencyTypes " .
                        "ON DependencyTypes.ID = PackageDepends.DepTypeID " .
                        "WHERE PackageDepends.PackageID = " . $pkgid . " " .
                        "UNION SELECT RelationTypes.Name AS Type, " .
                        "PackageRelations.RelName AS Name, " .
                        "PackageRelations.RelCondition AS Cond " .
                        "FROM PackageRelations " .
                        "LEFT JOIN RelationTypes " .
                        "ON RelationTypes.ID = PackageRelations.RelTypeID " .
                        "WHERE PackageRelations.PackageID = " . $pkgid . " " .
                        "UNION SELECT 'groups' AS Type, `Groups`.`Name`, '' AS Cond " .
                        "FROM `Groups` INNER JOIN PackageGroups " .
                        "ON PackageGroups.PackageID = " . $pkgid . " " .
                        "AND PackageGroups.GroupID = `Groups`.ID " .
                        "UNION SELECT 'license' AS Type, Licenses.Name, '' AS Cond " .
                        "FROM Licenses INNER JOIN PackageLicenses " .
                        "ON PackageLicenses.PackageID = " . $pkgid . " " .
                        "AND PackageLicenses.LicenseID = Licenses.ID";
                $ttl = config_get_int('options', 'cache_pkginfo_ttl');
                $rows = db_cache_result($query, 'extended-fields:' . $pkgid, PDO::FETCH_ASSOC, $ttl);

                $type_map = array(
                        'depends' => 'Depends',
                        'makedepends' => 'MakeDepends',
                        'checkdepends' => 'CheckDepends',
                        'optdepends' => 'OptDepends',
                        'conflicts' => 'Conflicts',
                        'provides' => 'Provides',
                        'replaces' => 'Replaces',
                        'groups' => 'Groups',
                        'license' => 'License',
                );
                $data = array();
                foreach ($rows as $row) {
                        $type = $type_map[$row['Type']];
                        $data[$type][] = $row['Name'] . $row['Cond'];
                }

                if ($this->version >= 5) {
                        $query = "SELECT Keyword FROM PackageKeywords " .
                                "WHERE PackageBaseID = " . intval($base_id) . " " .
                                "ORDER BY Keyword ASC";
                        $ttl = config_get_int('options', 'cache_pkginfo_ttl');
                        $rows = db_cache_result($query, 'keywords:' . intval($base_id), PDO::FETCH_NUM, $ttl);
                        $data['Keywords'] = array_map(function ($x) { return $x[0]; }, $rows);
                }

                return $data;
        }

        /*
         * Retrieve package information (used in info, multiinfo, search and
         * depends requests).
         *
         * @param $type The request type.
         * @param $where_condition An SQL WHERE-condition to filter packages.
         *
         * @return mixed Returns an array of package matches.
         */
        private function process_query($type, $where_condition) {
                $max_results = config_get_int('options', 'max_rpc_results');

                if ($this->version == 1) {
                        $fields = implode(',', self::$fields_v1);
                        $query = "SELECT {$fields} " .
                                "FROM Packages LEFT JOIN PackageBases " .
                                "ON PackageBases.ID = Packages.PackageBaseID " .
                                "LEFT JOIN Users " .
                                "ON PackageBases.MaintainerUID = Users.ID " .
                                "LEFT JOIN PackageLicenses " .
                                "ON PackageLicenses.PackageID = Packages.ID " .
                                "LEFT JOIN Licenses " .
                                "ON Licenses.ID = PackageLicenses.LicenseID " .
                                "WHERE ${where_condition} " .
                                "AND PackageBases.PackagerUID IS NOT NULL " .
                                "LIMIT $max_results";
                } elseif ($this->version >= 2) {
                        if ($this->version == 2 || $this->version == 3) {
                                $fields = implode(',', self::$fields_v2);
                        } else if ($this->version >= 4 && $this->version <= 6) {
                                $fields = implode(',', self::$fields_v4);
                        }
                        $query = "SELECT {$fields} " .
                                "FROM Packages LEFT JOIN PackageBases " .
                                "ON PackageBases.ID = Packages.PackageBaseID " .
                                "LEFT JOIN Users " .
                                "ON PackageBases.MaintainerUID = Users.ID " .
                                "WHERE ${where_condition} " .
                                "AND PackageBases.PackagerUID IS NOT NULL " .
                                "LIMIT $max_results";
                }
                $result = $this->dbh->query($query);

                if ($result) {
                        $resultcount = 0;
                        $search_data = array();
                        while ($row = $result->fetch(PDO::FETCH_ASSOC)) {
                                $resultcount++;
                                $row['URLPath'] = sprintf(config_get('options', 'snapshot_uri'), urlencode($row['PackageBase']));
                                if ($this->version < 4) {
                                        $row['CategoryID'] = 1;
                                }

                                /*
                                 * Unfortunately, mysql_fetch_assoc() returns
                                 * all fields as strings. We need to coerce
                                 * numeric values into integers to provide
                                 * proper data types in the JSON response.
                                 */
                                foreach (self::$numeric_fields as $field) {
                                        if (isset($row[$field])) {
                                                $row[$field] = intval($row[$field]);
                                        }
                                }

                                foreach (self::$decimal_fields as $field) {
                                        if (isset($row[$field])) {
                                                $row[$field] = floatval($row[$field]);
                                        }
                                }

                                if ($this->version >= 2 && ($type == 'info' || $type == 'multiinfo')) {
                                        $extfields = $this->get_extended_fields($row['ID'], $row['PackageBaseID']);
                                        if ($extfields) {
                                                $row = array_merge($row, $extfields);
                                        }
                                }

                                if ($this->version < 3) {
                                        if ($type == 'info') {
                                                $search_data = $row;
                                                break;
                                        } else {
                                                array_push($search_data, $row);
                                        }
                                } elseif ($this->version >= 3) {
                                        array_push($search_data, $row);
                                }
                        }

                        if ($resultcount === $max_results) {
                                return $this->json_error('Too many package results.');
                        }

                        return $this->json_results($type, $resultcount, $search_data, NULL);
                } else {
                        return $this->json_results($type, 0, array(), NULL);
                }
        }

        /*
         * Parse the args to the multiinfo function. We may have a string or an
         * array, so do the appropriate thing. Within the elements, both * package
         * IDs and package names are valid; sort them into the relevant arrays and
         * escape/quote the names.
         *
         * @param array $args Query parameters.
         *
         * @return mixed An array containing 'ids' and 'names'.
         */
        private function parse_multiinfo_args($args) {
                if (!is_array($args)) {
                        $args = array($args);
                }

                $id_args = array();
                $name_args = array();
                foreach ($args as $arg) {
                        if (!$arg) {
                                continue;
                        }
                        if ($this->version < 5 && is_numeric($arg)) {
                                $id_args[] = intval($arg);
                        } else {
                                $name_args[] = $this->dbh->quote($arg);
                        }
                }

                return array('ids' => $id_args, 'names' => $name_args);
        }

        /*
         * Performs a fulltext mysql search of the package database.
         *
         * @param array $http_data Query parameters.
         *
         * @return mixed Returns an array of package matches.
         */
        private function search($http_data) {
                $keyword_string = $http_data['arg'];

                if (isset($http_data['by'])) {
                        $search_by = $http_data['by'];
                } else {
                        $search_by = 'name-desc';
                }

                if ($search_by === 'name' || $search_by === 'name-desc') {
                        if (strlen($keyword_string) < 2) {
                                return $this->json_error('Query arg too small.');
                        }

                        if ($this->version >= 6 && $search_by === 'name-desc') {
                                $where_condition = construct_keyword_search($this->dbh,
                                        $keyword_string, true, false);
                        } else {
                                $keyword_string = $this->dbh->quote(
                                        "%" . addcslashes($keyword_string, '%_') . "%");

                                if ($search_by === 'name') {
                                        $where_condition = "(Packages.Name LIKE $keyword_string)";
                                } else if ($search_by === 'name-desc') {
                                        $where_condition = "(Packages.Name LIKE $keyword_string ";
                                        $where_condition .= "OR Description LIKE $keyword_string)";
                                }

                        }
                } else if ($search_by === 'maintainer') {
                        if (empty($keyword_string)) {
                                $where_condition = "Users.ID is NULL";
                        } else {
                                $keyword_string = $this->dbh->quote($keyword_string);
                                $where_condition = "Users.Username = $keyword_string ";
                        }
                } else if (in_array($search_by, self::$exposed_depfields)) {
                        if (empty($keyword_string)) {
                                return $this->json_error('Query arg is empty.');
                        } else {
                                $keyword_string = $this->dbh->quote($keyword_string);
                                $search_by = $this->dbh->quote($search_by);
                                $subquery = "SELECT PackageDepends.DepName FROM PackageDepends ";
                                $subquery .= "LEFT JOIN DependencyTypes ";
                                $subquery .= "ON PackageDepends.DepTypeID = DependencyTypes.ID ";
                                $subquery .= "WHERE PackageDepends.PackageID = Packages.ID ";
                                $subquery .= "AND DependencyTypes.Name = $search_by";
                                $where_condition = "$keyword_string IN ($subquery)";
                        }
                }

                return $this->process_query('search', $where_condition);
        }

        /*
         * Returns the info on a specific package.
         *
         * @param array $http_data Query parameters.
         *
         * @return mixed Returns an array of value data containing the package data
         */
        private function info($http_data) {
                $pqdata = $http_data['arg'];
                if ($this->version < 5 && is_numeric($pqdata)) {
                        $where_condition = "Packages.ID = $pqdata";
                } else {
                        $where_condition = "Packages.Name = " . $this->dbh->quote($pqdata);
                }

                return $this->process_query('info', $where_condition);
        }

        /*
         * Returns the info on multiple packages.
         *
         * @param array $http_data Query parameters.
         *
         * @return mixed Returns an array of results containing the package data
         */
        private function multiinfo($http_data) {
                $pqdata = $http_data['arg'];
                $args = $this->parse_multiinfo_args($pqdata);
                $ids = $args['ids'];
                $names = $args['names'];

                if (!$ids && !$names) {
                        return $this->json_error('Invalid query arguments.');
                }

                $where_condition = "";
                if ($ids) {
                        $ids_value = implode(',', $args['ids']);
                        $where_condition .= "Packages.ID IN ($ids_value) ";
                }
                if ($ids && $names) {
                        $where_condition .= "OR ";
                }
                if ($names) {
                        /*
                         * Individual names were quoted in
                         * parse_multiinfo_args().
                         */
                        $names_value = implode(',', $args['names']);
                        $where_condition .= "Packages.Name IN ($names_value) ";
                }

                return $this->process_query('multiinfo', $where_condition);
        }

        /*
         * Returns all the packages for a specific maintainer.
         *
         * @param array $http_data Query parameters.
         *
         * @return mixed Returns an array of value data containing the package data
         */
        private function msearch($http_data) {
                $http_data['by'] = 'maintainer';
                return $this->search($http_data);
        }

        /*
         * Get all package names that start with $search.
         *
         * @param array $http_data Query parameters.
         *
         * @return string The JSON formatted response data.
         */
        private function suggest($http_data) {
                $search = $http_data['arg'];
                $query = "SELECT Packages.Name FROM Packages ";
                $query.= "LEFT JOIN PackageBases ";
                $query.= "ON PackageBases.ID = Packages.PackageBaseID ";
                $query.= "WHERE Packages.Name LIKE ";
                $query.= $this->dbh->quote(addcslashes($search, '%_') . '%');
                $query.= " AND PackageBases.PackagerUID IS NOT NULL ";
                $query.= "ORDER BY Name ASC LIMIT 20";

                $result = $this->dbh->query($query);
                $result_array = array();

                if ($result) {
                        $result_array = $result->fetchAll(PDO::FETCH_COLUMN, 0);
                }

                return json_encode($result_array);
        }

        /*
         * Get all package base names that start with $search.
         *
         * @param array $http_data Query parameters.
         *
         * @return string The JSON formatted response data.
         */
        private function suggest_pkgbase($http_data) {
                $search = $http_data['arg'];
                $query = "SELECT Name FROM PackageBases WHERE Name LIKE ";
                $query.= $this->dbh->quote(addcslashes($search, '%_') . '%');
                $query.= " AND PackageBases.PackagerUID IS NOT NULL ";
                $query.= "ORDER BY Name ASC LIMIT 20";

                $result = $this->dbh->query($query);
                $result_array = array();

                if ($result) {
                        $result_array = $result->fetchAll(PDO::FETCH_COLUMN, 0);
                }

                return json_encode($result_array);
        }

        /**
         * Get the HTML markup of the comment form.
         *
         * @param array $http_data Query parameters.
         *
         * @return string The JSON formatted response data.
         */
        private function get_comment_form($http_data) {
                if (!isset($http_data['base_id']) || !isset($http_data['pkgbase_name'])) {
                        $output = array(
                                'success' => 0,
                                'error' => __('Package base ID or package base name missing.')
                        );
                        return json_encode($output);
                }

                $comment_id = intval($http_data['arg']);
                $base_id = intval($http_data['base_id']);
                $pkgbase_name = $http_data['pkgbase_name'];

                list($user_id, $comment) = comment_by_id($comment_id);

                if (!has_credential(CRED_COMMENT_EDIT, array($user_id))) {
                        $output = array(
                                'success' => 0,
                                'error' => __('You are not allowed to edit this comment.')
                        );
                        return json_encode($output);
                } elseif (is_null($comment)) {
                        $output = array(
                                'success' => 0,
                                'error' => __('Comment does not exist.')
                        );
                        return json_encode($output);
                }

                ob_start();
                include('pkg_comment_form.php');
                $html = ob_get_clean();
                $output = array(
                        'success' => 1,
                        'form' => $html
                );

                return json_encode($output);
        }
}