Implement simple attachment support

It is now possible to upload and view attachments!

Attachments are saved by their content hash, therefore they are
automatically deduplicated and we can later easily add integrity checks.

Still missing:
- Deleting attachments
- Multiple file inputs (idea: when the user fills in a file input, create a
  new empty file input beneath with js)
- (nice to have) Thumbnails

1 files changed, 9 insertions, 0 deletions

diff --git a/src/Env.php b/src/Env.php
index 34b9f1f..38d9279 100644
--- a/src/Env.php
+++ b/src/Env.php
@@ -2,6 +2,7 @@
 
 namespace Micropoly;
 
+use RuntimeException;
 use SQLite3;
 use Twig\Environment;
 use Twig\Loader\FilesystemLoader;
@@ -77,4 +78,12 @@ class Env
             return $db;
         });
     }
+
+    public function attachmentsPath(): string
+    {
+        $attachments = $this->config['attachments'];
+        if (!is_dir($attachments) || !is_writable($attachments))
+            throw new RuntimeException("Attachment directory '$attachments' is not a writable directory.");
+        return $attachments;
+    }
 }