Feature: Usage of config file.

MANIFEST.in

@@ -1,5 +1,4 @@
 include README.md
 include LICENSE
-include cfg/config.yml
 include bin/ethunder
 recursive-include ethunder/test *.py

ethunder/__init__.py

@@ -2,9 +2,9 @@
 """
     EnlightedThunder
     ~~~~~~~
-    
+
     A project to explore the possibilites of GitHub and Python deployment.
-    
+
     This is a personal discovery and not considered usefull for other. It's
     probabliy best if you just ignore it.
 
@@ -13,3 +13,6 @@
 """
 
 __version__ = "0.1.0"
+
+class EThunderError(Exception):
+    pass

ethunder/app.py

@@ -14,14 +14,16 @@
 import os.path
 import sys
 
-import yaml
 import docopt
-import appdirs
 import ethunder
+from ethunder.config import configurate
 
 __author__ = "Richard Pfeifer"
 
-configpath = appdirs.user_config_dir("ethunder", appauthor=None)
+
+class EThunderError(Exception):
+    pass
+
 
 def parse_commandline(argv):
     """
@@ -37,29 +39,18 @@ def parse_commandline(argv):
     return arguments
 
 
-def parse_config():
-    """
-    Read the YAML config-file.
-    """
-    with open(os.path.join(configpath, "config.yml"), 'r') as configfile:
-	cfg = yaml.load(configfile)
-    ethunder.value1 = cfg['value1']
-    ethunder.path_to_rainbow = cfg['path_to_rainbow']
-    ethunder.is_awesome = cfg['is_awesome']
-
-
 def print_message():
     awesome_negation = "not "
-    if ethunder.is_awesome:
+    if ethunder.config["is_awesome"]:
         awesome_negation = ""
     msg = (
         "Hello world. This is ethunder and it is {0}awesome!\n"
         "\tRainbow can be found at: {1}\n"
-	"\tvalue1 = {2}"
+        "\tvalue1 = {2}"
     ).format(
-	awesome_negation,
-	os.path.normpath(ethunder.path_to_rainbow),
-	ethunder.value1
+        awesome_negation,
+        os.path.normpath(ethunder.config["path_to_rainbow"]),
+        ethunder.config["value1"]
     )
     print(msg)
 
@@ -68,8 +59,8 @@ def Main():
     parse_commandline(sys.argv[1:])
 
     try:
-	parse_config()
-	print_message()
+        configurate()
+        print_message()
     except KeyboardInterrupt:
         print("Shutdown requested...exiting")
     sys.exit(0)

ethunder/config.py

@@ -0,0 +1,109 @@
+# -*- coding: utf-8 -*-
+"""
+Provide tools to load configuration parameters from text-file using YAML.
+"""
+
+from __future__ import print_function
+from __future__ import unicode_literals
+
+import yaml
+import os.path
+import appdirs
+import shutil
+import datetime
+import ethunder
+from ethunder import EThunderError
+
+__author__ = "Richard Pfeifer"
+
+
+config_dir = appdirs.user_config_dir("ethunder", appauthor=None)
+config_filename = "config.yml"
+
+default_config = {
+    "path_to_rainbow": "ick schwörs µus",
+    "value1": 0,
+    "is_awesome": True,
+}
+
+
+class NoValidConfigfileError(EThunderError):
+    pass
+
+
+def construct_yaml_str(self, node):
+    """
+    Override the default string handling function to always return unicode
+    objects.
+    """
+    return self.construct_scalar(node)
+yaml.Loader.add_constructor("tag:yaml.org,2002:str", construct_yaml_str)
+yaml.SafeLoader.add_constructor("tag:yaml.org,2002:str", construct_yaml_str)
+
+
+def create_default_configfile():
+    """
+    Create a configfile with default config-values at the configpath.
+    """
+    config_path = os.path.join(config_dir, config_filename)
+    if os.path.isfile(config_path):
+        backup_filename = "config_backup_{0}.yml".format(
+            datetime.datetime.now().isoformat())
+        backup_filename = backup_filename.replace(":", "-")
+        backup_filepath = os.path.join(config_dir, backup_filename)
+        shutil.move(config_path, backup_filepath)
+    with open(config_path, 'w') as config_out_file:
+        d = yaml.safe_dump(
+            ethunder.config,
+            default_flow_style=False,
+            encoding=('utf-8'),
+            allow_unicode=True)
+        print(d)
+        config_out_file.write(d)
+
+def set_config():
+    """
+    Set configuration either from YAML config-file or from defaults.
+    """
+    configpath = os.path.join(config_dir, config_filename)
+    ethunder.config = {}
+    ethunder.config.update(default_config)
+    try:
+        try:
+            print("try open")
+            with open(configpath, 'r') as configfile:
+                print("opened")
+                try:
+                    cfg = yaml.safe_load(configfile)
+                except Exception as e:
+                    print("error while loading: {0}".format(e))
+                    raise NoValidConfigfileError(e)
+                else:
+                    print("should have cfg")
+        except IOError:
+            print("create empty cfg")
+            cfg = {}
+            raise NoValidConfigfileError(
+                "config.yml not found at {0}".format(configpath))
+        else:
+            if not isinstance(cfg, dict):
+                raise NoValidConfigfileError(
+                    "Invalid configfile at {0}".format(configpath))
+    except NoValidConfigfileError:
+        raise
+    else:
+        ethunder.config.update(cfg)
+        print("Following config was read: {0}".format(ethunder.config))
+
+
+def configurate():
+    """
+    Make sure we have the needed configuration values.
+    """
+    try:
+        set_config()
+    except NoValidConfigfileError:
+        create_default_configfile()
+
+if __name__ == "__main__":
+    configurate()

setup.py

@@ -1,10 +1,7 @@
 from setuptools import setup
-import appdirs
 
 import ethunder
 
-config_dir = appdirs.user_config_dir("ethunder", appauthor=None)
-
 config = {
     'name': 'EThunder',
     'description': 'A test project.',
@@ -25,10 +22,9 @@
     'install_requires': ['docopt==0.6.1',
                          'appdirs==1.4.0',
                          'nose==1.3.4',
-			 'pyYaml==3.11',
-                         ],
+                         'pyYaml==3.11',
+                        ],
     'packages': ['ethunder', 'ethunder.test'],
-    'data_files': [(config_dir, ['cfg/config.yml'])],
     'include_package_data': True,
     'entry_points': {'console_scripts':
                         ['ethunder = ethunder.app:Main',