[Feature:System] RCOS Custom Mapping

student_auto_feed/config.php

@@ -3,9 +3,7 @@
 /* HEADING ---------------------------------------------------------------------
  *
  * config.php script used by submitty_student_auto_feed
- * By Peter Bailie, Systems Programmer (RPI dept of computer science)
- *
- * Requires minimum PHP version 7.3 with pgsql extension.
+ * By Peter Bailie, Renssealer Polytechnic Institute
  *
  * Configuration of submitty_student_auto_feed is structured through a series
  * of named constants.
@@ -117,6 +115,7 @@
 define('COLUMN_EMAIL',         4);  //Student's Campus Email
 define('COLUMN_TERM_CODE',     11); //Semester code used in data validation
 define('COLUMN_REG_ID',        12); //Course and Section registration ID
+define('COLUMN_CREDITS',       13); //Credits registered
 
 //Validate term code.  Set to null to disable this check.
 define('EXPECTED_TERM_CODE', '201705');
@@ -127,6 +126,25 @@
 //Set to true, if Submitty is using SAML for authentication.
 define('PROCESS_SAML', true);
 
+/* RENSSELAER CENTER FOR OPEN SOURCE (RCOS) -----------------------------------
+ * RCOS is not just one course, but several.  Some of these courses also
+ * permit a student to declare their credit load.  The data feed will need
+ * a column showing a student's credit load.  See above: COLUMN_CREDITS
+ *
+ * Create only one RCOS course in Submitty, which will show up in the
+ * grader's/instructor's course list.  The other RCOS courses must be mapped to
+ * this first course.  Registration sections do need to be fully mapped, as the
+ * database does not permit mapping NULL sections.  However, the upsert process
+ * will override how RCOS enrollments are translated, so that registration
+ * sections are, per student, "{course}-{credits}"  e.g. J. Doe is enrolled in
+ * RCOS course CSCI4700 for 4 credits.  They will be listed as enrolled in
+ * registration section "CSCI4700-4"
+ */
+
+// List *ALL* RCOS courses, as an array.
+// If you are not tracking RCOS, then set this as null or an empty array.
+define('RCOS_COURSE_LIST', null);
+
 /* DATA SOURCING --------------------------------------------------------------
  * The Student Autofeed provides helper scripts to retrieve the CSV file for
  * processing.  Shell script ssaf.sh is used to invoke one of the helper

student_auto_feed/readme.md

@@ -10,9 +10,9 @@ policies and practices.__
 
 Detailed instructions can be found at [http://submitty.org/sysadmin/student\_auto\_feed](http://submitty.org/sysadmin/student_auto_feed)
 
-Requirements: PHP 7.3 or higher with pgsql extension.  `imap_remote.php` also
-requires the imap extension.  This system is intended to be platform agnostic,
-but has been developed and tested with Ubuntu Linux.
+Requires the pgsql extension.  `imap_remote.php` also requires the imap extension.
+This system is intended to be platform agnostic, but has been developed and tested
+with Ubuntu Linux.
 
 ## submitty\_student\_auto\_feed.php
 A command line executable script to read a student enrollment data CSV file and

student_auto_feed/ssaf_rcos.php

@@ -0,0 +1,30 @@
+<?php
+namespace ssaf;
+
+/**
+ * Static utilty class to support RCOS (Rensselaer Center for Open Source)
+ *
+ * This will override enrollment registration sections for RCOS courses to `{course}-{credits}`  e.g. `CSCI4700-4`.
+ * Some RCOS students may declare how many credits they are registering for, so normal course mapping in the database
+ * is insufficient.  This must done while processing the CSV because every override requires each student's registered
+ * credits from the CSV.
+ *
+ * @author Peter Bailie
+ */
+class rcos {
+    private array $course_list;
+
+    public function __construct() {
+        $this->course_list = RCOS_COURSE_LIST ?? [];
+        array_walk($this->course_list, function(&$v, $i) { $v = strtolower($v); });
+        sort($this->course_list, SORT_STRING);
+    }
+
+    /** Adjusts `$row[COLUMN_SECTION]` when `$course` is an RCOS course. */
+    public function map(string $course, array &$row): void {
+        if (in_array($course, $this->course_list, true)) {
+            $course = strtoupper($course);
+            $row[COLUMN_SECTION] = "{$course}-{$row[COLUMN_CREDITS]}";
+        }
+    }
+}

student_auto_feed/ssaf_validate.php

@@ -74,48 +74,6 @@ public static function validate_row($row, $row_num) : bool {
         return true;
     }
 
-    /**
-     * Check $rows for duplicate user IDs.
-     *
-     * Submitty's master DB does not permit students to register more than once
-     * for any course.  It would trigger a key violation exception.  This
-     * function checks for data anomalies where a student shows up in a course
-     * more than once as that is indicative of an issue with CSV file data.
-     * Returns TRUE, as in no error, when $rows has all unique user IDs.
-     * False, as in error found, otherwise.  $user_ids is filled when return
-     * is FALSE.
-     *
-     * @param array $rows Data rows to check (presumably an entire couse).
-     * @param string[] &$user_id Duplicated user ID, when found.
-     * @param string[] &$d_rows Rows containing duplicate user IDs, indexed by user ID.
-     * @return bool TRUE when all user IDs are unique, FALSE otherwise.
-     */
-    public static function check_for_duplicate_user_ids(array $rows, &$user_ids, &$d_rows) : bool {
-        usort($rows, function($a, $b) { return $a[COLUMN_USER_ID] <=> $b[COLUMN_USER_ID]; });
-
-        $user_ids = [];
-        $d_rows = [];
-        $are_all_unique = true;  // Unless proven FALSE
-        $length = count($rows);
-        for ($i = 1; $i < $length; $i++) {
-            $j = $i - 1;
-            if ($rows[$i][COLUMN_USER_ID] === $rows[$j][COLUMN_USER_ID]) {
-                $are_all_unique = false;
-                $user_id = $rows[$i][COLUMN_USER_ID];
-                $user_ids[] = $user_id;
-                $d_rows[$user_id][] = $j;
-                $d_rows[$user_id][] = $i;
-            }
-        }
-
-        foreach($d_rows as &$d_row) {
-            array_unique($d_row, SORT_REGULAR);
-        }
-        unset($d_row);
-
-        return $are_all_unique;
-    }
-
     /**
      * Validate that there isn't an excessive drop ratio in course enrollments.
      *

student_auto_feed/submitty_student_auto_feed.php

@@ -5,7 +5,7 @@
  *
  * This script will read a student enrollment CSV feed provided by the campus
  * registrar or data warehouse and "upsert" (insert/update) the feed into
- * Submitty's course databases.  Requires PHP 7.3 and pgsql extension.
+ * Submitty's course databases.  Requires pgsql extension.
  *
  * @author Peter Bailie, Rensselaer Polytechnic Institute
  */
@@ -15,6 +15,7 @@
 require __DIR__ . "/ssaf_cli.php";
 require __DIR__ . "/ssaf_db.php";
 require __DIR__ . "/ssaf_validate.php";
+require __DIR__ . "/ssaf_rcos.php";
 
 // Important: Make sure we are running from CLI
 if (php_sapi_name() !== "cli") {
@@ -27,22 +28,24 @@
 
 /** primary process class */
 class submitty_student_auto_feed {
-    /** @var resource File handle to read CSV */
+    /** File handle to read CSV */
     private $fh;
-    /** @var string Semester code */
-    private $semester;
-    /** @var array List of courses registered in Submitty */
-    private $course_list;
-    /** @var array Describes how courses are mapped from one to another */
-    private $mapped_courses;
-    /** @var array Describes courses/sections that are duplicated to other courses/sections */
-    private $crn_copymap;
-    /** @var array Courses with invalid data. */
-    private $invalid_courses;
-    /** @var array All CSV data to be upserted */
-    private $data;
-    /** @var string Ongoing string of messages to write to logfile */
-    private $log_msg_queue;
+    /** Semester code */
+    private string $semester;
+    /** List of courses registered in Submitty */
+    private array $course_list;
+    /** Describes how courses are mapped from one to another */
+    private array $mapped_courses;
+    /** Describes courses/sections that are duplicated to other courses/sections */
+    private array $crn_copymap;
+    /** Courses with invalid data. */
+    private array $invalid_courses;
+    /** All CSV data to be upserted */
+    private array $data;
+    /** Ongoing string of messages to write to logfile */
+    private string $log_msg_queue;
+    /** For special cases involving Renssealer Center for Open Source */
+    private object $rcos;
 
     /** Init properties.  Open DB connection.  Open CSV file. */
     public function __construct() {
@@ -100,6 +103,9 @@ public function __construct() {
         // Get CRN shared courses/sections (when a course/section is copied to another course/section)
         $this->crn_copymap = $this->read_crn_copymap();
 
+        // Helper object for special-cases involving RCOS.
+        $this->rcos = new rcos();
+
         // Init other properties.
         $this->invalid_courses = [];
         $this->data = [];
@@ -135,8 +141,8 @@ public function go() {
         case $this->check_for_excessive_dropped_users():
             // This check will block all upserts when an error is detected.
             exit(1);
-        case $this->check_for_duplicate_user_ids():
-            $this->log_it("Duplicate user IDs detected in CSV file.");
+        case $this->filter_duplicate_registrations():
+            // Never returns false.  Error messages are already in log queue.
             break;
         case $this->invalidate_courses():
             // Should do nothing when $this->invalid_courses is empty
@@ -185,15 +191,15 @@ private function get_csv_data() {
         // Read and assign csv rows into $this->data array
         $row = fgetcsv($this->fh, 0, CSV_DELIM_CHAR);
         while(!feof($this->fh)) {
-            // Course is comprised of an alphabetic prefix and a numeric suffix.
-            $course = strtolower($row[COLUMN_COURSE_PREFIX] . $row[COLUMN_COURSE_NUMBER]);
-
             // Trim whitespace from all fields in $row.
             array_walk($row, function(&$val, $key) { $val = trim($val); });
 
             // Remove any leading zeroes from "integer" registration sections.
             if (ctype_digit($row[COLUMN_SECTION])) $row[COLUMN_SECTION] = ltrim($row[COLUMN_SECTION], "0");
 
+            // Course is comprised of an alphabetic prefix and a numeric suffix.
+            $course = strtolower($row[COLUMN_COURSE_PREFIX] . $row[COLUMN_COURSE_NUMBER]);
+
             switch(true) {
             // Check that $row has an appropriate student registration.
             case array_search($row[COLUMN_REGISTRATION], $all_valid_reg_codes) === false:
@@ -212,6 +218,9 @@ private function get_csv_data() {
             // Check that $row is associated with the course list.
             case array_search($course, $this->course_list) !== false:
                 if (validate::validate_row($row, $row_num)) {
+                    // Check (and perform) special-case RCOS registration section mapping.
+                    $this->rcos->map($course, $row);
+
                     // Include $row
                     $this->data[$course][] = $row;
 
@@ -233,8 +242,13 @@ private function get_csv_data() {
                 if (array_key_exists($section, $this->mapped_courses[$course])) {
                     $m_course = $this->mapped_courses[$course][$section]['mapped_course'];
                     if (validate::validate_row($row, $row_num)) {
-                        // Include $row.
+                        // Do course mapping (alters registration section).
                         $row[COLUMN_SECTION] = $this->mapped_courses[$course][$section]['mapped_section'];
+
+                        // Check (and override) for special-case RCOS registration section mapping.
+                        $this->rcos->map($course, $row);
+
+                        // Include $row.
                         $this->data[$m_course][] = $row;
 
                         // $row with a blank email is allowed, but it is also logged.
@@ -285,31 +299,31 @@ private function get_csv_data() {
     }
 
     /**
-     * Users cannot be registered to the same course multiple times.
+     * Students cannot be registered to the same course multiple times.
      *
-     * Any course with a user registered more than once is flagged invalid as
-     * it is indicative of data errors from the CSV file.
-     *
-     * @return bool always TRUE
+     * If multiple registrations for the same student and course are found, the first instance is allowed to be
+     * upserted to the database.  All other instances are removed from the data set and therefore not upserted.
      */
-    private function check_for_duplicate_user_ids() {
-        foreach($this->data as $course => $rows) {
-            $user_ids = null;
-            $d_rows = null;
-            // Returns FALSE (as in there is an error) when duplicate IDs are found.
-            // However, a duplicate ID does not invalidate a course.  Instead, the
-            // first enrollment is accepted, the other enrollments are discarded,
-            // and the event is logged.
-            if (validate::check_for_duplicate_user_ids($rows, $user_ids, $d_rows) === false) {
-                foreach($d_rows as $user_id => $userid_rows) {
-                    $length = count($userid_rows);
-                    for ($i = 1; $i < $length; $i++) {
-                        unset($this->data[$course][$userid_rows[$i]]);
-                    }
+    private function filter_duplicate_registrations(): true {
+        foreach($this->data as $course => &$rows) {
+            usort($rows, function($a, $b) { return $a[COLUMN_USER_ID] <=> $b[COLUMN_USER_ID]; });
+            $duplicated_ids = [];
+            $num_rows = count($rows);
+
+            // We are iterating from bottom to top through a course's data set.  Should we find a duplicate registration
+            // and unset it from the array, (1) we are unsetting duplicates starting from the bottom, (2) which preserves
+            // the first entry among duplicate entries, and (3) we do not make a comparison with a null key.
+            for ($j = $num_rows - 1, $i = $j - 1; $i >= 0; $i--, $j--) {
+                if ($rows[$i][COLUMN_USER_ID] === $rows[$j][COLUMN_USER_ID]) {
+                    $duplicated_ids[] = $rows[$j][COLUMN_USER_ID];
+                    unset($rows[$j]);
                 }
+            }
 
+            if (count($duplicated_ids) > 0) {
+                array_unique($duplicated_ids, SORT_STRING);
                 $msg = "Duplicate user IDs detected in {$course} data: ";
-                $msg .= implode(", ", $user_ids);
+                $msg .= implode(", ", $duplicated_ids);
                 $this->log_it($msg);
             }
         }