Incidents: archive incident attachments

There is no handling of file types as explained in the `archive`
docstring. Testing indicates that relaying incidents with e.g. a text
file attachment is simply a noop in the Discord GUI.

If there is at least one attachment, we always only relay the one
at index 0, as it is believed the user-sent messages can only contain
one attachment at maximum.

This also adds an extra test asserting the behaviour when an incident
with an attachment is archived. The existing test for `archive` is
adjusted to assume no attachments.

Joe helped me conceive & test this.

Co-authored-by: Joseph Banks <[email protected]>

2 files changed, 50 insertions, 1 deletions

diff --git a/bot/cogs/moderation/incidents.py b/bot/cogs/moderation/incidents.py
index 8970c2c5c..1a12c8bbd 100644
--- a/bot/cogs/moderation/incidents.py
+++ b/bot/cogs/moderation/incidents.py
@@ -186,22 +186,41 @@ class Incidents(Cog):
 
         The following pieces of information are relayed:
             * Incident message content (as embed description)
+            * Incident attachment (if image, shown in archive embed)
             * Incident author name (as webhook author)
             * Incident author avatar (as webhook avatar)
             * Resolution signal `outcome` (as embed colour & footer)
             * Moderator `actioned_by` (name & discriminator shown in footer)
 
+        If `incident` contains an attachment, we try to add it to the archive embed. There is
+        no handing of extensions / file types - we simply dispatch the attachment file with the
+        webhook, and try to display it in the embed. Testing indicates that if the attachment
+        cannot be displayed (e.g. a text file), it's invisible in the embed, with no error.
+
         Return True if the relay finishes successfully. If anything goes wrong, meaning
         not all information was relayed, return False. This signals that the original
         message is not safe to be deleted, as we will lose some information.
         """
         log.debug(f"Archiving incident: {incident.id} (outcome: {outcome}, actioned by: {actioned_by})")
+        embed = make_embed(incident, outcome, actioned_by)
+
+        # If the incident had an attachment, we will try to relay it
+        if incident.attachments:
+            attachment = incident.attachments[0]  # User-sent messages can only contain one attachment
+            log.debug(f"Attempting to archive incident attachment: {attachment.filename}")
+
+            attachment_file = await attachment.to_file()  # The file will be sent with the webhook
+            embed.set_image(url=f"attachment://{attachment.filename}")  # Embed displays the attached file
+        else:
+            attachment_file = None
+
         try:
             webhook = await self.bot.fetch_webhook(Webhooks.incidents_archive)
             await webhook.send(
-                embed=make_embed(incident, outcome, actioned_by),
+                embed=embed,
                 username=sub_clyde(incident.author.name),
                 avatar_url=incident.author.avatar_url,
+                file=attachment_file,
             )
         except Exception:
             log.exception(f"Failed to archive incident {incident.id} to #incidents-archive")
diff --git a/tests/bot/cogs/moderation/test_incidents.py b/tests/bot/cogs/moderation/test_incidents.py
index 70dfe6b5f..f8d479cef 100644
--- a/tests/bot/cogs/moderation/test_incidents.py
+++ b/tests/bot/cogs/moderation/test_incidents.py
@@ -323,6 +323,7 @@ class TestArchive(TestIncidents):
             content="this is an incident",
             author=MockUser(name="author_name", avatar_url="author_avatar"),
             id=123,
+            attachments=[],  # This incident has no attachments
         )
         built_embed = MagicMock(discord.Embed, id=123)  # We patch `make_embed` to return this
 
@@ -334,9 +335,38 @@ class TestArchive(TestIncidents):
             embed=built_embed,
             username="author_name",
             avatar_url="author_avatar",
+            file=None,
         )
         self.assertTrue(archive_return)
 
+    async def test_archive_relays_incident_with_attachments(self):
+        """
+        Incident attachments are relayed and displayed in the embed.
+
+        This test asserts the two things that need to happen in order to relay the attachment.
+        The embed returned by `make_embed` must have the `set_image` method called with the
+        attachment's filename, and the file must be passed to the webhook's send method.
+        """
+        attachment_file = MagicMock(discord.File)
+        attachment = MagicMock(
+            discord.Attachment,
+            filename="abc.png",
+            to_file=AsyncMock(return_value=attachment_file),
+        )
+        incident = MockMessage(
+            attachments=[attachment],
+        )
+        built_embed = MagicMock(discord.Embed)
+
+        with patch("bot.cogs.moderation.incidents.make_embed", MagicMock(return_value=built_embed)):
+            await self.cog_instance.archive(incident, incidents.Signal.ACTIONED, actioned_by=MockMember())
+
+        built_embed.set_image.assert_called_once_with(url="attachment://abc.png")
+
+        send_kwargs = self.cog_instance.bot.fetch_webhook.return_value.send.call_args.kwargs
+        self.assertIn("file", send_kwargs)
+        self.assertIs(send_kwargs["file"], attachment_file)
+
     async def test_archive_clyde_username(self):
         """
         The archive webhook username is cleansed using `sub_clyde`.