/*
* Get an array of courses (with magic extra bits)
- * where the access sess data shows that the cap
- * requested is available.
+ * where the access sess data and in DB enrolments show
+ * that the cap requested is available.
*
* The main use is for get_my_courses().
*
* - the course records have $c->context which is a fully
* valid context object. Saves you a query per course!
*
- * - current implementation is _extremely_ stupid but
- * works fast enough. We can surely do much MUCH better
- * for the common cases, and leave the brute-force to
- * "not-easy-to-narrow-down" cases.
+ * - current implementation is split in -
+ *
+ * - if the user has the cap systemwide, stupidly
+ * grab *every* course for a capcheck. This eats
+ * a TON of bandwidth, specially on large sites
+ * with separate DBs...
+ *
+ * - otherwise, fetch "likely" courses with a wide net
+ * that should get us _cheaply_ at least the courses we need, and some
+ * we won't - we get courses that...
+ * - are in a category where user has the cap
+ * - or where use has a role-assignment (any kind)
+ * - or where the course has an override on for this cap
+ *
+ * - walk the courses recordset checking the caps oneach one
+ * the checks are all in memory and quite fast
+ * (though we could implement a specialised variant of the
+ * has_cap_fromsess() code to speed it up)
*
* @param string $capability - name of the capability
* @param array $sess - access session array
* @return array $courses - ordered array of course objects - see notes above
*
*/
-function get_courses_bycap_fromsess($cap, $sess, $doanything, $sort='c.sortorder ASC', $fields=NULL, $limit=0) {
+function get_user_courses_bycap($userid, $cap, $sess, $doanything, $sort='c.sortorder ASC', $fields=NULL, $limit=0) {
global $CFG;
} else {
$fields = $basefields;
}
-
$coursefields = 'c.' .join(',c.', $fields);
-
- $sql = "SELECT $coursefields,
- ctx.id AS ctxid, ctx.path AS ctxpath, ctx.depth as ctxdepth
- FROM {$CFG->prefix}course c
- JOIN {$CFG->prefix}context ctx
- ON (c.id=ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSE.")
- ORDER BY $sort;
- ";
+
+ $sysctx = get_context_instance(CONTEXT_SYSTEM);
+ if (has_cap_fromsess($cap, $sysctx, $sess, $doanything)) {
+ //
+ // Apparently the user has the cap sitewide, so walk *every* course
+ // (the cap checks are moderately fast, but this moves massive bandwidth w the db)
+ // Yuck.
+ //
+ $sql = "SELECT $coursefields,
+ ctx.id AS ctxid, ctx.path AS ctxpath, ctx.depth as ctxdepth
+ FROM {$CFG->prefix}course c
+ JOIN {$CFG->prefix}context ctx
+ ON (c.id=ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSE.")
+ ORDER BY $sort;
+ ";
+ $rs = get_recordset_sql($sql);
+ } else {
+ //
+ // narrow down where we have the caps to a few contexts
+ // this will be a combination of
+ // - categories where we have the rights
+ // - courses where we have an explicit enrolment OR that have an override
+ //
+ $sql = "SELECT ctx.*
+ FROM {$CFG->prefix}context ctx
+ WHERE ctx.contextlevel=".CONTEXT_COURSECAT."
+ ORDER BY ctx.depth";
+ $rs = get_recordset_sql($sql);
+ $catpaths = array();
+ if ($rs->RecordCount()) {
+ while ($catctx = rs_fetch_next_record($rs)) {
+ if ($catctx->path != ''
+ && has_cap_fromsess($cap, $catctx, $sess, $doanything)) {
+ $catpaths[] = $catctx->path;
+ }
+ }
+ }
+ rs_close($rs);
+ $catclause = '';
+ if (count($catpaths)) {
+ $cc = count($catpaths);
+ for ($n=0;$n<$cc;$n++) {
+ $catpaths[$n] = "ctx.path LIKE '{$catpaths[$n]}/%'";
+ }
+ $catclause = 'OR (' . join(' OR ', $catpaths) .')';
+ }
+ unset($catpaths);
+ //
+ // Note here that we *have* to have the compound clauses
+ // in the LEFT OUTER JOIN condition for them to return NULL
+ // appropriately and narrow things down...
+ //
+ $sql = "SELECT $coursefields,
+ ctx.id AS ctxid, ctx.path AS ctxpath, ctx.depth as ctxdepth
+ FROM {$CFG->prefix}course c
+ JOIN {$CFG->prefix}context ctx
+ ON (c.id=ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSE.")
+ LEFT OUTER JOIN {$CFG->prefix}role_assignments ra
+ ON (ra.contextid=ctx.id AND ra.userid=$userid)
+ LEFT OUTER JOIN {$CFG->prefix}role_capabilities rc
+ ON (rc.contextid=ctx.id AND rc.capability='$cap')
+ WHERE ra.id IS NOT NULL
+ OR rc.id IS NOT NULL
+ $catclause
+ ORDER BY $sort;
+ ";
+ $rs = get_recordset_sql($sql);
+ }
$courses = array();
$cc = 0; // keep count
- $rs = get_recordset_sql($sql);
if ($rs->RecordCount()) {
while ($c = rs_fetch_next_record($rs)) {
// build the context obj
* List of courses that a user has access to view. Note that for admins,
* this usually includes every course on the system.
*
- * Notes (inherited from get_courses_bycap_fromsess()):
+ * Notes (inherited from get_user_courses_bycap()):
*
* - $fields is an array of fieldnames to ADD
* so name the fields you really need, which will
$fields = NULL;
} else {
// turn the fields from a string to an array that
- // get_courses_bycap_fromsess() will like...
+ // get_user_courses_bycap() will like...
$fields = explode(',',$fields);
$fields = array_map('trim', $fields);
}
} else {
$accessinfo = get_user_access_sitewide($userid);
}
- $courses = get_courses_bycap_fromsess('moodle/course:view', $accessinfo,
- $doanything, $sort, $fields,
- $limit);
+ $courses = get_user_courses_bycap($userid, 'moodle/course:view', $accessinfo,
+ $doanything, $sort, $fields,
+ $limit);
// strangely, get_my_courses() is expected to return the
// array keyed on id, which messes up the sorting
$kcourses = array();
projects / moodle.git / commitdiff