MVC - add exportCsv() to ApiControllerBase to easily stream recordset…

…s as csv files to the client and add asRecordSet() to ArrayField to be able to use this easily.

Sometimes it's practical to be able to use tools like excel to modify data, in order to do this we need an import and an export option in the model.
The export seems to be quite easy, controllers and forms can easily use this with a construction like:

$this->exportCsv($mymodel->myarray->asRecordSet());

The import is likely a bit more challenging.

src/opnsense/mvc/app/controllers/OPNsense/Base/ApiControllerBase.php

@@ -135,6 +135,34 @@ protected function searchRecordsetBase(
         ];
     }
 
+    /**
+     * passtru recordset (key value store) as csv output
+     * @param array $records dataset to export (e.g. [['field' => 'value'], ['field' => 'value']])
+     */
+    protected function exportCsv(
+        $records,
+        $headers = [
+            'Content-Type: text/csv', 'Content-Transfer-Encoding: binary', 'Pragma: no-cache', 'Expires: 0'
+        ]
+    ) {
+        $records = is_array($records) ? $records : [];
+        $stream = fopen('php://temp', 'rw+');
+        if (isset($records[0])) {
+            fputcsv($stream, array_keys($records[0]));
+        }
+        foreach ($records as $record) {
+            fputcsv($stream, $record);
+        }
+        fseek($stream, 0);
+        foreach ($headers as $header) {
+            header($header);
+        }
+        ob_end_flush();
+        rewind($stream);
+        fpassthru($stream);
+        fclose($stream);
+    }
+
     /**
      * passtru configd stream
      * @param string $action configd action to perform

src/opnsense/mvc/app/models/OPNsense/Base/FieldTypes/ArrayField.php

@@ -264,4 +264,26 @@ public function isFieldChanged()
         }
         return false;
     }
+
+    /**
+     * @param bool $include_static include non importable static items
+     * @param array $exclude fieldnames to exclude
+     * @return array simple array set
+     */
+    public function asRecordSet($include_static=false, $exclude = [])
+    {
+        $records = [];
+        $iterator =  $include_static ? $this->iterateItems() : parent::iterateItems();
+        foreach ($iterator as $akey => $anode)
+        {
+            $record = [];
+            foreach ($anode->iterateItems() as $tag => $node) {
+                if (!in_array($tag, $exclude)) {
+                    $record[$tag] = (string)$node;
+                }
+            }
+            $records[] = $record;
+        }
+        return $records;
+    }
 }