From 2329bb1555a5df543abe2a993d334c7616ab6cb7 Mon Sep 17 00:00:00 2001
From: Yaroslav Klyuyev <imposeren@gmail.com>
Date: Mon, 16 Mar 2015 22:12:13 +0200
Subject: [PATCH] added utils.file_adapter

utils.file_adapter should be used when source type may be file-like
object or path to file. Used in FromCSVTablesGenerator and in
FromTablesGenerator. Should resolve #6
---
 pynames/from_tables_generator.py | 10 +++++-----
 pynames/tests/test_utils.py      | 24 ++++++++++++++++++++++--
 pynames/utils.py                 | 14 +++++++++++++-
 3 files changed, 40 insertions(+), 8 deletions(-)

diff --git a/pynames/from_tables_generator.py b/pynames/from_tables_generator.py
index c5ad26f..1052b5d 100644
--- a/pynames/from_tables_generator.py
+++ b/pynames/from_tables_generator.py
@@ -13,7 +13,7 @@ from pynames import exceptions
 from pynames.base import BaseGenerator
 from pynames.names import Name
 from pynames.relations import GENDER, LANGUAGE, LANGUAGE_FORMS_LANGTH
-from pynames.utils import is_file
+from pynames.utils import file_adapter
 
 
 class Template(object):
@@ -104,7 +104,7 @@ class FromTablesGenerator(BaseGenerator):
             error_msg = 'FromTablesGenerator: you must make subclass of FromTablesGenerator and define attribute SOURCE in it.'
             raise NotImplementedError(error_msg)
 
-        with open(source) as f:
+        with file_adapter(source) as f:
             data = json.load(f)
             self.native_language = data['native_language']
             self.languages = set(data['languages'])
@@ -237,7 +237,7 @@ class FromCSVTablesGenerator(FromTablesGenerator):
         self.full_forms_for_languages = set()
 
     def load_settings(self, settings_source):
-        with (settings_source if is_file(settings_source) else open(settings_source)) as settings_file:
+        with file_adapter(settings_source) as settings_file:
             reader = unicodecsv.DictReader(settings_file, encoding='utf-8')
             for row in reader:
                 new_native_language = row.get('native_language', '').strip()
@@ -258,7 +258,7 @@ class FromCSVTablesGenerator(FromTablesGenerator):
     def load_templates(self, templates_source):
         template_slugs = []
 
-        with (templates_source if is_file(templates_source) else open(templates_source)) as templates_file:
+        with file_adapter(templates_source) as templates_file:
             reader = unicodecsv.DictReader(templates_file, encoding='utf-8')
             for row in reader:
                 template_data = {
@@ -275,7 +275,7 @@ class FromCSVTablesGenerator(FromTablesGenerator):
         return template_slugs
 
     def load_tables(self, tables_source):
-        with (tables_source if is_file(tables_source) else open(tables_source)) as tables_file:
+        with file_adapter(tables_source) as tables_file:
             reader = unicodecsv.DictReader(tables_file, encoding='utf-8')
             slugs = set([fieldname.split(':')[0] for fieldname in reader.fieldnames])
             for slug in slugs:
diff --git a/pynames/tests/test_utils.py b/pynames/tests/test_utils.py
index fc58a2c..c97c02e 100644
--- a/pynames/tests/test_utils.py
+++ b/pynames/tests/test_utils.py
@@ -1,9 +1,11 @@
 # coding: utf-8
 
-import unittest
+import os
 import tempfile
+import unittest
 
-from pynames.utils import is_file
+from pynames.utils import is_file, file_adapter
+import pynames
 
 try:
     from django.core.files import File
@@ -27,3 +29,21 @@ class TestName(unittest.TestCase):
             self.assertTrue(is_file(UploadedFile('mock')))
             self.assertTrue(is_file(File('mock')))
             self.assertTrue(is_file(ContentFile('mock')))
+
+    def test_file_dapter(self):
+        root_dir = os.path.dirname(pynames.__file__)
+
+        test_file_path = os.path.join(root_dir, 'tests', 'fixtures', 'test_from_list_generator.json')
+
+        with open(test_file_path) as f:
+            target_content = f.read()
+
+        with file_adapter(test_file_path) as f:
+            self.assertEqual(f.read(), target_content)
+
+        django_file_object = ContentFile(target_content)
+        classic_file_object = open(test_file_path, 'r')
+
+        for tested_file_object in [django_file_object, classic_file_object]:
+            with file_adapter(tested_file_object) as f:
+                self.assertEqual(f.read(), target_content)
diff --git a/pynames/utils.py b/pynames/utils.py
index a0e1c0b..5aa5cac 100644
--- a/pynames/utils.py
+++ b/pynames/utils.py
@@ -1,7 +1,8 @@
 # coding: utf-8
 
-import os
+import contextlib
 import importlib
+import os
 
 import pynames
 
@@ -54,3 +55,14 @@ def is_file(obj):
         +
         [any([callable(getattr(obj, method_name, None)) for method_name in ('next', '__iter__')])]
     )
+
+
+@contextlib.contextmanager
+def file_adapter(file_or_path):
+    """Context manager that works similar to ``open(file_path)``but also accepts already openned file-like objects."""
+    if is_file(file_or_path):
+        file_obj = file_or_path
+    else:
+        file_obj = open(file_or_path)
+    yield file_obj
+    file_obj.close()