feat(api): Add inplace_to_s3 management command

This command allows to update Uploads that originally were imported
using --in_place but are moved to s3. This command does not copy any
file, it just makes sure the files are read from S3 after they have been
moved.

Part-of: <https://dev.funkwhale.audio/funkwhale/funkwhale/-/merge_requests/2506>

api/tests/common/test_commands.py

@@ -1,4 +1,5 @@
 import os
+from io import StringIO
 
 import pytest
 from django.core.management import call_command
@@ -116,3 +117,56 @@ def test_unblocked_commands(command, mocker):
     mocker.patch.dict(os.environ, {"FORCE": "1"})
 
     call_command(command)
+
+
+def test_inplace_to_s3_without_source():
+    with pytest.raises(CommandError):
+        call_command("inplace_to_s3")
+
+
+def test_inplace_to_s3_dryrun(factories):
+    upload = factories["music.Upload"](in_place=True, source="file:///music/music.mp3")
+    call_command("inplace_to_s3", "--source", "/music")
+    assert upload.source == "file:///music/music.mp3"
+    assert upload.audio_file is None
+
+
+data = [
+    {
+        "file": "/music/test.mp3",
+        "source": "/",
+        "target": None,
+        "expected": "/music/test.mp3",
+    },
+    {
+        "file": "/music/test.mp3",
+        "source": "/music",
+        "target": "/in-place",
+        "expected": "/in-place/test.mp3",
+    },
+    {
+        "file": "/music/test.mp3",
+        "source": "/music",
+        "target": "/in-place/music",
+        "expected": "/in-place/music/test.mp3",
+    },
+    {"file": "/music/test.mp3", "source": "/abcd", "target": "/music", "expected": "0"},
+]
+
+
+@pytest.mark.parametrize("data", data)
+def test_inplace_to_s3(factories, data):
+    out = StringIO()
+    factories["music.Upload"](in_place=True, source=f"file://{data['file']}")
+    if data["target"]:
+        call_command(
+            "inplace_to_s3",
+            "--source",
+            data["source"],
+            "--target",
+            data["target"],
+            stdout=out,
+        )
+    else:
+        call_command("inplace_to_s3", "--source", data["source"], stdout=out)
+    assert data["expected"] in out.getvalue()