All users to set a custom configuration file

Author: hush-hush

CHANGELOG.md

@@ -3,6 +3,7 @@ CHANGELOG
 
 # 2.2.0 / 2017-12-27
 - [FEATURE] Set log level to warning for the datadog and request packages. See [#24][] (thanks to @n0ts)
+- [FEATURE] Allow users to set a custom location for the configuration file.
 
 # 2.1.0 / 2017-12-26
 - [FEATURE] Disable callback if required python packages aren't installed. See [#28][] (thanks to @dobber)

README.md

@@ -29,7 +29,15 @@ as following:
 api_key: <your-api-key>
 ```
 
-alternatively you can use the hostvars of the host ansible is being run from (preferably in the vault file):
+You can specify a custom location for the configuration file using the
+`ANSIBLE_DATADOG_CALLBACK_CONF_FILE` environment file.
+
+For exemple:
+```
+ANSIBLE_DATADOG_CALLBACK_CONF_FILE=/etc/datadog/callback_conf.yaml ansible-playbook ...
+```
+
+Alternatively you can use the hostvars of the host ansible is being run from (preferably in the vault file):
 ```
 datadog_api_key: <your-api-key>
 ```

datadog_callback.py

@@ -1,6 +1,6 @@
 import getpass
-import os.path
 import logging
+import os
 import time
 
 try:
@@ -49,12 +49,15 @@ def _set_logger_level(self, name, level=logging.WARNING):
             print e
 
     # Load parameters from conf file
-    def _load_conf(self, file_path):
-        conf_dict = {}
+    def _load_conf(self):
+        file_path = os.environ.get('ANSIBLE_DATADOG_CALLBACK_CONF_FILE', os.path.join(os.path.dirname(__file__), "datadog_callback.yml"))
 
+        conf_dict = {}
         if os.path.isfile(file_path):
             with open(file_path, 'r') as conf_file:
                 conf_dict = yaml.load(conf_file)
+        else:
+            print "Could not load configuration, invalid file: {}".format(file_path)
 
         return conf_dict.get('api_key', ''), conf_dict.get('url', 'https://app.datadoghq.com')
 
@@ -226,7 +229,7 @@ def v2_playbook_on_play_start(self, play):
             return
 
         # Read config and hostvars
-        api_key, url = self._load_conf(os.path.join(os.path.dirname(__file__), "datadog_callback.yml"))
+        api_key, url = self._load_conf()
         # If there is no api key defined in config file, try to get it from hostvars
         if api_key == '':
             hostvars = self.play.get_variable_manager()._hostvars
@@ -238,7 +241,7 @@ def v2_playbook_on_play_start(self, play):
                 try:
                     api_key = hostvars['localhost']['datadog_api_key']
                 except Exception, e:
-                    print '{0} is not set neither in the config file nor hostvars: disabling Datadog callback plugin'.format(e)
+                    print 'No "api_key" found in the config file and {0} is not set in the hostvars: disabling Datadog callback plugin'.format(e)
                     self.disabled = True
 
         # Set up API client and send a start event