feat(credentials): Initiate service based on credential file

Author: ehdsouza

test/unit/test_watson_service.py

@@ -217,3 +217,9 @@ def test_has_bad_first_or_last_char():
     with pytest.raises(ValueError) as err:
         AnyServiceV1('2018-11-20', iam_apikey='apikey', url='"url"')
     assert str(err.value) == 'The URL shouldn\'t start or end with curly brackets or quotes. Be sure to remove any {} and \" characters surrounding your URL'
+
+@responses.activate
+def test__set_credential_based_on_type():
+    service = AnyServiceV1('2018-11-20', username='username', password='password')
+    service._set_credential_based_on_type('test', 'test_apikey', 'xxx')
+    assert service.iam_apikey == 'xxx'

watson_developer_cloud/iam_token_manager.py

@@ -111,6 +111,12 @@ def set_iam_apikey(self, iam_apikey):
         """
         self.iam_apikey = iam_apikey
 
+    def set_iam_url(self, iam_url):
+        """
+        Set the IAM url
+        """
+        self.iam_url = iam_url
+
     def _is_token_expired(self):
         """
         Check if currently stored token is expired.

watson_developer_cloud/watson_service.py

@@ -15,6 +15,7 @@
 import json as json_import
 import platform
 import os
+from os.path import dirname, isfile, join, expanduser, abspath
 import requests
 import sys
 from requests.structures import CaseInsensitiveDict
@@ -33,7 +34,13 @@
 AUTH_HEADER_DEPRECATION_MESSAGE = 'Authenticating with the X-Watson-Authorization-Token header is deprecated. The token continues to work with Cloud Foundry services, but is not supported for services that use Identity and Access Management (IAM) authentication.'
 ICP_PREFIX = 'icp-'
 APIKEY = 'apikey'
+URL = 'url'
+USERNAME = 'username'
+PASSWORD = 'password'
+IAM_APIKEY = 'iam_apikey'
+IAM_URL = 'iam_url'
 APIKEY_DEPRECATION_MESSAGE = 'Authenticating with apikey is deprecated. Move to using Identity and Access Management (IAM) authentication.'
+DEFAULT_CREDENTIALS_FILE_NAME = 'ibm-credentials.env'
 
 # Uncomment this to enable http debugging
 # try:
@@ -53,7 +60,6 @@ def load_from_vcap_services(service_name):
     else:
         return None
 
-
 class WatsonException(Exception):
     """
     Custom exception class for Watson Services.
@@ -259,6 +265,8 @@ def __init__(self, vcap_services_name, url, username=None, password=None,
         elif iam_access_token is not None or iam_apikey is not None:
             self.set_token_manager(iam_apikey, iam_access_token, iam_url)
 
+        self.load_from_credential_file(vcap_services_name)
+
         if use_vcap_services and not self.username and not self.api_key:
             self.vcap_service_credentials = load_from_vcap_services(
                 vcap_services_name)
@@ -282,6 +290,50 @@ def __init__(self, vcap_services_name, url, username=None, password=None,
                 'You must specify your IAM api key or username and password service '
                 'credentials (Note: these are different from your Bluemix id)')
 
+    def load_from_credential_file(self, service_name, separator='='):
+        """
+        Initiates the credentials based on the credential file
+
+        :param str service_name: The service name
+        :param str separator: the separator for key value pair
+        """
+        # File path specified by an env variable
+        credential_file_path = os.getenv("IBM_CREDENTIALS_FILE")
+
+        # Home directory
+        if credential_file_path is None:
+            file_path = join(expanduser('~'), DEFAULT_CREDENTIALS_FILE_NAME)
+            if isfile(file_path):
+                credential_file_path = file_path
+
+        # Top-level of the project directory
+        if credential_file_path is None:
+            file_path = join(dirname(dirname(abspath(__file__))), DEFAULT_CREDENTIALS_FILE_NAME)
+            if isfile(file_path):
+                credential_file_path = file_path
+
+        if credential_file_path is not None:
+            with open(credential_file_path, 'rb') as fp:
+                for line in fp:
+                    key_val = line.strip().split(separator)
+                    self._set_credential_based_on_type(service_name, key_val[0].lower(), key_val[1].lower())
+
+
+    def _set_credential_based_on_type(self, service_name, key, value):
+        if service_name in key:
+            if APIKEY in key:
+                self.set_iam_apikey(value)
+            elif URL in key:
+                self.set_url(value)
+            elif USERNAME in key:
+                self.username = value
+            elif PASSWORD in key:
+                self.password = value
+            elif IAM_APIKEY in key:
+                self.set_iam_apikey(value)
+            elif IAM_URL in key:
+                self.set_iam_url(value)
+
     def set_username_and_password(self, username=None, password=None):
         if username == 'YOUR SERVICE USERNAME':
             username = None
@@ -335,6 +387,14 @@ def set_iam_access_token(self, iam_access_token):
         self.iam_access_token = iam_access_token
         self.jar = CookieJar()
 
+    def set_iam_url(self, iam_url):
+        if self.token_manager:
+            self.token_manager.set_iam_url(iam_url)
+        else:
+            self.token_manager = IAMTokenManager(iam_url=iam_url)
+        self.iam_url = iam_url
+        self.jar = CookieJar()
+
     def set_iam_apikey(self, iam_apikey):
         if _has_bad_first_or_last_char(iam_apikey):
             raise ValueError('The credentials shouldn\'t start or end with curly brackets or quotes. '