allow Content-ID to be set on email attachments

.gitignore

@@ -17,3 +17,4 @@ yarn-error.log*
 /js/public/logo.png
 /.mypy_cache/
 /activate.sh
+/scratch/

aioaws/ses.py

@@ -40,6 +40,7 @@ class SesAttachment:
     file: Union[Path, bytes]
     name: Optional[str] = None
     mime_type: Optional[str] = None
+    content_id: Optional[str] = None
 
 
 @dataclass
@@ -188,7 +189,11 @@ async def prepare_attachment(a: SesAttachment) -> Tuple[MIMEBase, int]:
     msg.set_payload(data)
     encode_base64(msg)
 
-    msg.add_header('Content-Disposition', 'attachment', filename=filename)
+    if a.content_id is None:
+        msg.add_header('Content-Disposition', 'attachment', filename=filename)
+    else:
+        msg.add_header('Content-ID', a.content_id)
+        msg.add_header('Content-Disposition', 'inline', filename=filename)
     return msg, len(data)
 
 

aioaws/testing.py

@@ -22,8 +22,9 @@ def ses_email_data(data: Dict[str, str]) -> Dict[str, Any]:
     for part in msg.walk():
         if payload := part.get_payload(decode=True):
             part_info = {'Content-Type': part.get_content_type(), 'payload': payload.decode().replace('\r\n', '\n')}
-            if cd := part['Content-Disposition']:
-                part_info['Content-Disposition'] = cd
+            for key in 'Content-Disposition', 'Content-ID':
+                if cd := part[key]:
+                    part_info[key] = cd
             d['payload'].append(part_info)
 
     return {'body': dict(data), 'email': d}

tests/test_ses.py

@@ -248,6 +248,36 @@ async def test_custom_headers(client: AsyncClient, aws: DummyServer):
     }
 
 
+async def test_inline_attachment(client: AsyncClient, aws: DummyServer):
+    ses = SesClient(client, SesConfig('test_access_key', 'test_secret_key', 'testing-region-1'))
+
+    await ses.send_email(
+        'testing@sender.com',
+        'the subject',
+        ['testing@recipient.com'],
+        'this is a test email',
+        html_body='this is the <b>html body</b>.',
+        attachments=[SesAttachment(file=b'some attachment', name='foobar.txt', content_id='<testing-content-id>')],
+    )
+    assert len(aws.app['emails']) == 1
+    assert aws.app['emails'][0]['email']['payload'] == [
+        {
+            'Content-Type': 'text/plain',
+            'payload': 'this is a test email\n',
+        },
+        {
+            'Content-Type': 'text/html',
+            'payload': 'this is the <b>html body</b>.\n',
+        },
+        {
+            'Content-Type': 'text/plain',
+            'payload': 'some attachment',
+            'Content-Disposition': 'inline; filename="foobar.txt"',
+            'Content-ID': '<testing-content-id>',
+        },
+    ]
+
+
 async def test_encoded_unsub(client: AsyncClient, aws: DummyServer):
     ses = SesClient(client, SesConfig('test_access_key', 'test_secret_key', 'testing-region-1'))
     unsub_link = 'https://www.example.com/unsubscrible?blob=?blob=$MzMgMTYwMTY3MDEyOCBMMzcbN_nhcDZNg-6D=='