[Dashboard] Fix study progression performance

modules/dashboard/ajax/get_scan_line_data.php

@@ -25,94 +25,102 @@
 
 $DB = Database::singleton();
 
-$scanData           = array();
-$scanStartDate      = $DB->pselectOne(
+$scanData      = array();
+$scanStartDate = $DB->pselectOne(
     "SELECT MIN(pf.Value) 
      FROM parameter_file pf 
      JOIN parameter_type pt USING (ParameterTypeID) 
      WHERE pt.Name='acquisition_date'",
     array()
 );
-$scanEndDate        = $DB->pselectOne(
+$scanEndDate   = $DB->pselectOne(
     "SELECT MAX(pf.Value) 
      FROM parameter_file pf 
      JOIN parameter_type pt USING (ParameterTypeID) 
      WHERE pt.Name='acquisition_date'",
     array()
 );
-$scanData['labels']
-    = createLineChartLabels($scanStartDate, $scanEndDate);
-$list_of_sites      = Utility::getSiteList(true, false);
+
+// Run a query to get all the data. Order matters to ensure that the labels
+// are calculated in the correct order.
+$data = $DB->pselect(
+    "SELECT s.CenterID, 
+        CONCAT(MONTH(pf.Value), '-', YEAR(pf.Value)) as datelabel,
+        COUNT(distinct s.ID) as count
+    FROM files f
+        LEFT JOIN parameter_file pf USING (FileID)
+        LEFT JOIN session s ON (s.ID=f.SessionID)
+        JOIN parameter_type pt USING (ParameterTypeID)
+    WHERE pt.Name='acquisition_date'
+    GROUP BY MONTH(pf.Value), YEAR(pf.Value), s.CenterID
+    ORDER BY YEAR(pf.Value), MONTH(pf.Value), s.CenterID",
+    array()
+);
+
+$scanData['labels'] = createLineChartLabels($data);
+
+$list_of_sites = Utility::getSiteList(true, false);
 foreach ($list_of_sites as $siteID => $siteName) {
     $scanData['datasets'][] = array(
         "name" => $siteName,
-        "data" => getScanData($siteID, $scanData['labels']),
+        "data" => getScanData($data, $siteID, $scanData['labels'])
     );
 }
 
-print json_encode($scanData);
-
-return 0;
-
 /**
- * Create chart labels (dates)
+ * Massages the data passed into the format expected by the
+ * C3 library. Extracts the data for $siteID from $data, and
+ * ensures that each label has a value in the correct index
+ * of the returned array. Labels not in $data for site are
+ * given a value of 0.
  *
- * @param string $startDate start date of scans
- * @param string $endDate   end date of scans
+ * @param array $data   The data to be extracted from.
+ * @param int   $siteID The siteID to be extracted.
+ * @param array $labels A list of labels that should appear
+ *                      in the result in the correct order.
  *
- * @return array
+ * @return array The data for $siteID massaged into the correct form.
  */
-function createLineChartLabels($startDate, $endDate)
+function getScanData(array $data, int $siteID, array $labels)
 {
-    $startDateYear  = substr($startDate, 0, 4);
-    $endDateYear    = substr($endDate, 0, 4);
-    $startDateMonth = substr($startDate, 4, 2);
-    $endDateMonth   = substr($endDate, 4, 2);
-    $labels         = array();
-    for ($year = (int)$startDateYear; $year <= (int)$endDateYear; $year++) {
-        $startMonth = ($year == (int)$startDateYear) ? (int)$startDateMonth : 1;
-        $endMonth   = ($year == (int)$endDateYear) ? (int)$endDateMonth : 12;
-        for ($month = $startMonth; $month <= $endMonth; $month++) {
-            $labels[] = $month . "-" . $year;
+    $sitedata   = array_filter(
+        $data,
+        function ($row) use ($siteID) {
+            return $row['CenterID'] == $siteID;
         }
+    );
+    $mappeddata = [];
+    foreach ($sitedata as $row) {
+        $mappeddata[$row['datelabel']] = $row['count'];
+    }
+
+    $data = [];
+    foreach ($labels as $i => $label) {
+        $data[$i] = $mappeddata[$label] ?? 0;
     }
-    return $labels;
+    return $data;
 }
 
 /**
- * Get scan data for each month in the label array
+ * Extract all month labels that are in $data.
  *
- * @param string $siteID ID of a site
- * @param array  $labels chart labels (months to query)
+ * @param array $data The data to extract labels from
  *
- * @return array
+ * @return array An array of date labels that appear in the data.
  */
-function getScanData($siteID, $labels)
+function createLineChartLabels(array $data)
 {
-    $DB   = Database::singleton();
-    $data = array();
-    foreach ($labels as $label) {
-        $month  = (strlen($label) == 6)
-            ? substr($label, 0, 1) : substr($label, 0, 2);
-        $year   = substr($label, -4, 4);
-        $data[] = $DB->pselectOne(
-            "SELECT COUNT(distinct s.ID) 
-             FROM files f
-             LEFT JOIN parameter_file pf USING (FileID)
-             LEFT JOIN session s ON (s.ID=f.SessionID) 
-             JOIN parameter_type pt USING (ParameterTypeID)
-             WHERE s.CenterID=:Site
-             AND pt.Name='acquisition_date'
-             AND MONTH(pf.Value)=:Month 
-             AND YEAR(pf.Value)=:Year",
-            array(
-                'Site'  => $siteID,
-                'Month' => $month,
-                'Year'  => $year,
-            )
-        );
+    // Order was determined by the SQL statement. This should
+    // ensure that duplicates (for different sites) are stripped
+    // out.
+    $labels = [];
+    foreach ($data as $row) {
+        $labels[$row['datelabel']] = true;
     }
-    return $data;
+    return array_keys($labels);
 }
 
+print json_encode($scanData);
+
+return 0;