feat(base): Add method read_external_sources

Author: ehdsouza

ibm_cloud_sdk_core/base_service.py

@@ -21,7 +21,7 @@
 import requests
 from requests.structures import CaseInsensitiveDict
 from .version import __version__
-from .utils import has_bad_first_or_last_char, remove_null_values, cleanup_values, read_from_env_variables
+from .utils import has_bad_first_or_last_char, remove_null_values, cleanup_values, read_external_sources
 from .detailed_response import DetailedResponse
 from .api_exception import ApiException
 from .authenticators import Authenticator
@@ -65,7 +65,7 @@ def __init__(self,
 
         if display_name:
             service_name = display_name.replace(' ', '_').lower()
-            config = read_from_env_variables(service_name)
+            config = read_external_sources(service_name)
             if config.get('url'):
                 self.service_url = config.get('url')
             if config.get('disable_ssl'):

ibm_cloud_sdk_core/utils.py

@@ -54,29 +54,40 @@ def string_to_datetime(string):
     """
     return date_parser.parse(string)
 
-def get_authenticator_from_environment(service_name):
+def read_external_sources(service_name):
     """
-    Checks the credentials file and VCAP_SERVICES environment variable
+    Try to get config from external sources, with the following priority:
+    1. Credentials file(ibm-credentials.env)
+    2. Environment variables
+    3. VCAP Services(Cloud Foundry)
     :param service_name: The service name
-    :return: the authenticator
+    :return: dict
     """
-    authenticator = None
-    # 1. Credentials from credential file
+    config = {}
+
     config = read_from_credential_file(service_name)
-    if config:
-        authenticator = contruct_authenticator(config)
 
-    # 2. From env variables
-    if not authenticator:
+    if not config:
         config = read_from_env_variables(service_name)
-        if config:
-            authenticator = contruct_authenticator(config)
 
-    # 3. Credentials from VCAP
-    if not authenticator:
+    if not config:
         config = read_from_vcap_services(service_name)
-        if config:
-            authenticator = contruct_authenticator(config)
+
+    return config
+
+def get_authenticator_from_environment(service_name):
+    """
+    Try to get authenticator from external sources, with the following priority:
+    1. Credentials file(ibm-credentials.env)
+    2. Environment variables
+    3. VCAP Services(Cloud Foundry)
+    :param service_name: The service name
+    :return: the authenticator
+    """
+    authenticator = None
+    config = read_external_sources(service_name)
+    if config:
+        authenticator = contruct_authenticator(config)
     return authenticator
 
 def read_from_env_variables(service_name):
@@ -125,15 +136,15 @@ def read_from_credential_file(service_name, separator='='):
     return config
 
 def _parse_key_and_update_config(config, service_name, key, value):
-    if service_name in key:
+    if key.startswith(service_name):
         index = key.find('_')
         if index != -1:
             config[key[index + 1:]] = value
 
 def read_from_vcap_services(service_name):
     service_name = service_name.replace(' ', '_').lower()
     vcap_services = getenv('VCAP_SERVICES')
-    vcap_service_credentials = None
+    vcap_service_credentials = {}
     if vcap_services:
         services = json_import.loads(vcap_services)
 
@@ -147,7 +158,7 @@ def read_from_vcap_services(service_name):
                     elif vcap_service_credentials.get('apikey'):  # rc
                         vcap_service_credentials['auth_type'] = 'iam'
                     else: # no other auth mechanism is supported
-                        vcap_service_credentials = None
+                        vcap_service_credentials = {}
     return vcap_service_credentials
 
 def contruct_authenticator(config):

resources/ibm-credentials-iam.env

@@ -1,2 +1,4 @@
 WATSON_APIKEY=5678efgh
-WATSON_AUTH_TYPE=iam
+WATSON_AUTH_TYPE=iam
+WATSON_URL=https://gateway-s.watsonplatform.net/watson/api
+WATSON_DISABLE_SSL=False

test/test_base_service.py

@@ -139,13 +139,9 @@ def test_iam():
     file_path = os.path.join(
         os.path.dirname(__file__), '../resources/ibm-credentials-iam.env')
     os.environ['IBM_CREDENTIALS_FILE'] = file_path
-    os.environ['WATSON_URL'] = 'https://gateway-s.watsonplatform.net/watson/api'
-    os.environ['WATSON_DISABLE_SSL'] = 'False'
     service = AnyServiceV1('2017-07-07', authenticator=iam_authenticator)
     assert service.service_url == 'https://gateway-s.watsonplatform.net/watson/api'
     del os.environ['IBM_CREDENTIALS_FILE']
-    del os.environ['WATSON_URL']
-    del os.environ['WATSON_DISABLE_SSL']
     assert service.authenticator is not None
 
     response = {

test/test_utils.py

@@ -48,7 +48,7 @@ def test_get_authenticator_from_credential_file():
     assert authenticator.bearer_token is not None
     del os.environ['IBM_CREDENTIALS_FILE']
 
-def test_get_authenticator_from_env_variabled():
+def test_get_authenticator_from_env_variables():
     os.environ['TEST_APIKEY'] = '5678efgh'
     authenticator = get_authenticator_from_environment('test')
     assert authenticator is not None