Make application directory where data files are stored configurable #6 (#307)

Readme.md

@@ -170,7 +170,7 @@ Usage: elodie.py verify
 
 OK, so what if you don't like the folders being named `2015-07-Jul/Mountain View`? No problem!
 
-You can add a custom folder structure by editing your `config.ini` file (which should be placed under `~/.elodie/config.ini`).
+You can add a custom folder structure by editing your `config.ini` file (which should be placed under `~/.elodie/config.ini`). If you'd like to use a different folder for your configuration file then set an environment variable named `ELODIE_APPLICATION_DIRECTORY` with the fully qualified directory path.
 
 #### Custom folder examples
 

elodie/constants.py

@@ -2,14 +2,20 @@
 Settings used by Elodie.
 """
 
-from os import path
+from os import environ, path
 from sys import version_info
 
 #: If True, debug messages will be printed.
 debug = False
 
 #: Directory in which to store Elodie settings.
-application_directory = '{}/.elodie'.format(path.expanduser('~'))
+if (
+        'ELODIE_APPLICATION_DIRECTORY' in environ and
+        path.isdir(environ['ELODIE_APPLICATION_DIRECTORY'])
+   ):
+    application_directory = environ['ELODIE_APPLICATION_DIRECTORY']
+else:
+    application_directory = '{}/.elodie'.format(path.expanduser('~'))
 
 #: File in which to store details about media Elodie has seen.
 hash_db = '{}/hash.json'.format(application_directory)

elodie/tests/constants_test.py

@@ -0,0 +1,68 @@
+from __future__ import absolute_import
+# Project imports
+
+import os
+import sys
+import unittest 
+
+try:
+    reload  # Python 2.7
+except NameError:
+    try:
+        from importlib import reload  # Python 3.4+
+    except ImportError:
+        from imp import reload  # Python 3.0 - 3.3
+
+from mock import patch
+
+sys.path.insert(0, os.path.abspath(os.path.dirname(os.path.dirname(os.path.dirname(os.path.realpath(__file__))))))
+
+from elodie import constants
+
+BASE_PATH = os.path.dirname(os.path.dirname(os.path.dirname(os.path.realpath(__file__))))
+
+def test_debug():
+    # This seems pointless but on Travis we explicitly modify the file to be True
+    assert constants.debug == constants.debug, constants.debug
+
+def test_application_directory_default():
+    reload(constants)
+    expected_path = '{}/.elodie'.format(os.path.expanduser('~'))
+    assert constants.application_directory == expected_path, constants.application_directory
+
+def test_application_directory_override_invalid():
+    os.environ['ELODIE_APPLICATION_DIRECTORY'] = '/foo/bar'
+    reload(constants)
+    expected_path = '{}/.elodie'.format(os.path.expanduser('~'))
+    assert constants.application_directory == expected_path, constants.application_directory
+
+def test_application_directory_override_valid():
+    cwd = os.getcwd()
+    os.environ['ELODIE_APPLICATION_DIRECTORY'] = cwd
+    reload(constants)
+
+    assert constants.application_directory == cwd, constants.application_directory
+    assert cwd in constants.hash_db, constants.hash_db
+
+# must come after test_application_directory_override_valid due to env var reset
+def test_hash_db():
+    os.environ['ELODIE_APPLICATION_DIRECTORY'] = ''
+    reload(constants)
+    assert constants.hash_db == '{}/hash.json'.format(constants.application_directory), constants.hash_db
+
+def test_location_db():
+    assert constants.location_db == '{}/location.json'.format(constants.application_directory), constants.location_db
+
+def test_script_directory():
+    path = os.path.dirname(os.path.dirname(os.path.dirname(__file__)))
+    assert path == constants.script_directory, constants.script_directory
+
+def test_exiftool_config():
+    path = os.path.dirname(os.path.dirname(os.path.dirname(__file__)))
+    assert '{}/configs/ExifTool_config'.format(path) == constants.exiftool_config, constants.exiftool_config
+
+def test_accepted_language():
+    assert constants.accepted_language == 'en', constants.accepted_language
+
+def test_python_version():
+    assert constants.python_version == sys.version_info.major, constants.python_version