Feature: Creating Privacy Basics

src/Export/CsvColumn.php

@@ -0,0 +1,21 @@
+<?php
+
+namespace Modules\Core\Export;
+
+/**
+ * One column in a CsvWriter schema: a header label plus a closure that pulls this
+ * column's value out of one record. The closure doesn't care what shape a record
+ * is — an array, an Eloquent model, a DTO — so the same CsvWriter serves any
+ * domain (GDPR export, an admin catalog export, an accounting export) by simply
+ * being handed a different column schema and a different row source.
+ */
+final class CsvColumn
+{
+    /**
+     * @param  \Closure(mixed): (string|int|float|null)  $value
+     */
+    public function __construct(
+        public readonly string $header,
+        public readonly \Closure $value,
+    ) {}
+}

src/Export/CsvWriter.php

@@ -0,0 +1,45 @@
+<?php
+
+namespace Modules\Core\Export;
+
+/**
+ * A generic columns + rows -> CSV file writer. No knowledge of any domain (GDPR,
+ * catalog, accounting, ...) — a caller supplies the schema (CsvColumn[]) and the
+ * data source (any iterable of records), and this writes one CSV. Reusable for
+ * any future bulk-export need without modification.
+ */
+class CsvWriter
+{
+    /**
+     * @param  array<int, CsvColumn>  $columns
+     * @param  iterable<mixed>  $rows
+     */
+    public function write(array $columns, iterable $rows, string $path): void
+    {
+        $handle = fopen($path, 'w');
+
+        fputcsv($handle, array_map(fn (CsvColumn $column) => $column->header, $columns));
+
+        foreach ($rows as $row) {
+            fputcsv($handle, array_map(
+                fn (CsvColumn $column) => $this->stringify(($column->value)($row)),
+                $columns
+            ));
+        }
+
+        fclose($handle);
+    }
+
+    private function stringify(mixed $value): string
+    {
+        if ($value === null) {
+            return '';
+        }
+
+        if (is_array($value)) {
+            return json_encode($value);
+        }
+
+        return (string) $value;
+    }
+}