From 90cc7d381333c05333feb041ad4eb2a22af651d0 Mon Sep 17 00:00:00 2001
From: Benjamin Dauvergne <bdauvergne@entrouvert.com>
Date: Mon, 1 Aug 2022 19:28:39 +0200
Subject: [PATCH 1/2] add a binary file field (#66533)

---
 passerelle/utils/forms.py  | 76 ++++++++++++++++++++++++++++++++++++++
 passerelle/utils/models.py | 33 +++++++++++++++++
 2 files changed, 109 insertions(+)
 create mode 100644 passerelle/utils/forms.py
 create mode 100644 passerelle/utils/models.py

diff --git a/passerelle/utils/forms.py b/passerelle/utils/forms.py
new file mode 100644
index 00000000..cbb7b86d
--- /dev/null
+++ b/passerelle/utils/forms.py
@@ -0,0 +1,76 @@
+# passerelle - uniform access to multiple data sources and services
+# Copyright (C) 2022  Entr'ouvert
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from django import forms
+
+
+class BinaryFileInput(forms.ClearableFileInput):
+    def is_initial(self, value):
+        """
+        Return whether value is considered to be initial value.
+        """
+        return bool(value)
+
+    def format_value(self, value):
+        """Format the size of the value in the db.
+
+        We can't render it's name or url, but we'd like to give some information
+        as to wether this file is not empty/corrupt.
+        """
+        if self.is_initial(value):
+            return f'{len(value)} bytes'
+
+    def value_from_datadict(self, data, files, name):
+        """Return the file contents so they can be put in the db."""
+        upload = super().value_from_datadict(data, files, name)
+        if upload:
+            return upload.read()
+        return upload
+
+
+class BinaryFileField(forms.FileField):
+    widget = BinaryFileInput
+
+    def __init__(self, *, max_length=None, **kwargs):
+        self.max_length = max_length
+        super().__init__(**kwargs)
+
+    def to_python(self, value):
+        return value
+
+    def clean(self, data, initial=None):
+        # False means the field value should be cleared; further validation is
+        # not needed.
+        if data is False:
+            if not self.required:
+                return None
+            # If the field is required, clearing is not possible (the widget
+            # shouldn't return False data in that case anyway). False is not
+            # in self.empty_value; if a False value makes it this far
+            # it should be validated from here on out as None (so it will be
+            # caught by the required check).
+            data = None
+        if not data and initial:
+            return initial
+        return super(forms.FileField, self).clean(data)
+
+    def bound_data(self, data, initial):
+        if data is None:
+            return initial
+        return data
+
+    def has_changed(self, initial, data):
+        return not self.disabled and data is not None
diff --git a/passerelle/utils/models.py b/passerelle/utils/models.py
new file mode 100644
index 00000000..ab6500e0
--- /dev/null
+++ b/passerelle/utils/models.py
@@ -0,0 +1,33 @@
+# passerelle - uniform access to multiple data sources and services
+# Copyright (C) 2022  Entr'ouvert
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from django.db import models
+
+
+class BinaryFileField(models.BinaryField):
+    def __init__(self, *args, **kwargs):
+        kwargs.setdefault('editable', True)
+        super().__init__(*args, **kwargs)
+
+    def formfield(self, **kwargs):
+        from .forms import BinaryFileField
+
+        return super().formfield(
+            **{
+                'form_class': BinaryFileField,
+                **kwargs,
+            }
+        )
-- 
2.36.1