Add hopefully generic FileFieldRenderer

Eventually should refactor other (batch) things to use this.

tailbone/forms/renderers/__init__.py

@@ -33,6 +33,8 @@ from .common import (StrippedTextFieldRenderer, CodeTextAreaFieldRenderer, Autoc
                      DateTimeFieldRenderer, DateTimePrettyFieldRenderer, TimeFieldRenderer,
                      EnumFieldRenderer, YesNoFieldRenderer)
 
+from .files import FileFieldRenderer
+
 from .people import (PersonFieldRenderer, PersonFieldLinkRenderer,
                      CustomerFieldRenderer, CustomerFieldLinkRenderer)
 

tailbone/forms/renderers/batch.py

@@ -34,6 +34,7 @@ from formalchemy.ext import fsblob
 from formalchemy.fields import FileFieldRenderer as Base
 
 
+# TODO: make this inherit from `tailbone.forms.renderers.files.FileFieldRenderer`
 class FileFieldRenderer(fsblob.FileFieldRenderer):
     """
     Custom file field renderer for batches based on a single source data file.

tailbone/forms/renderers/files.py

@@ -0,0 +1,98 @@
+# -*- coding: utf-8 -*-
+################################################################################
+#
+#  Rattail -- Retail Software Framework
+#  Copyright © 2010-2016 Lance Edgar
+#
+#  This file is part of Rattail.
+#
+#  Rattail 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.
+#
+#  Rattail 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 Rattail.  If not, see <http://www.gnu.org/licenses/>.
+#
+################################################################################
+"""
+Batch Field Renderers
+"""
+
+from __future__ import unicode_literals, absolute_import
+
+import os
+import stat
+import random
+
+from formalchemy.ext import fsblob
+from formalchemy.fields import FileFieldRenderer as Base
+
+
+class FileFieldRenderer(fsblob.FileFieldRenderer):
+    """
+    Custom file field renderer.  In readonly mode, shows a filename and its
+    size; in edit mode, supports a single file upload.
+    """
+
+    @classmethod
+    def new(cls, view, **kwargs):
+        name = b'Configured{}_{}'.format(cls.__name__, str(random.random())[2:])
+        return type(name, (cls,), dict(view=view, **kwargs))
+
+    @property
+    def request(self):
+        return self.view.request
+
+    @property
+    def storage_path(self):
+        return self.view.upload_dir
+
+    def get_file_path(self):
+        """
+        Returns the absolute path to the data file.
+        """
+        if hasattr(self, 'file_path'):
+            return self.file_path
+        return self.field.value
+
+    def get_size(self):
+        """
+        Returns the size of the data file, in bytes.
+        """
+        path = self.get_file_path()
+        if path and os.path.isfile(path):
+            return os.stat(path)[stat.ST_SIZE]
+        return 0
+
+    def get_url(self, filename):
+        url = self.get_download_url()
+        if url:
+            if callable(url):
+                return url(filename)
+            return url
+
+    def get_download_url(self):
+        if hasattr(self, 'download_url'):
+            return self.download_url
+
+    def render(self, **kwargs):
+        return Base.render(self, **kwargs)
+
+    def render_readonly(self, **kwargs):
+        """
+        Render the filename and the binary size in a human readable with a link
+        to the file itself.
+        """
+        value = self.get_file_path()
+        if value:
+            content = '{} ({})'.format(fsblob.normalized_basename(value),
+                                       self.readable_size())
+            return fsblob.h.content_tag('a', content,
+                                        href=self.get_url(value), **kwargs)
+        return ''