Added support for token-based authentication; added get_subscribers function to MultiTenantCumulocityApp.

Author: chsou

c8y_api/__init__.py

@@ -7,3 +7,4 @@
 from c8y_api._base_api import CumulocityRestApi
 from c8y_api._main_api import CumulocityApi
 from c8y_api._registry_api import CumulocityDeviceRegistry
+from c8y_api._auth import HTTPBasicAuth, HTTPBearerAuth

c8y_api/_auth.py

@@ -22,6 +22,7 @@ def __init__(self, token: str):
 
     def __call__(self, r):
         r.headers['Authorization'] = 'Bearer ' + self.token
+        return r
 
 
 class AuthUtil:

c8y_api/app/__init__.py

@@ -11,13 +11,13 @@
 from cachetools import TTLCache
 from requests.auth import HTTPBasicAuth, AuthBase
 
-from c8y_api._auth import AuthUtil
+from c8y_api._auth import AuthUtil, HTTPBearerAuth
 from c8y_api._main_api import CumulocityApi
 from c8y_api._util import c8y_keys
 
 
 class _CumulocityAppBase(object):
-    """Internal class, base for both Per Tenant and Multi Tenant specifc
+    """Internal class, base for both Per Tenant and Multi Tenant specific
     implementation."""
 
     def __init__(self, log: logging.Logger, cache_size: int = 100, cache_ttl: int = 3600, **kwargs):
@@ -37,7 +37,7 @@ def get_user_instance(self, headers: dict = None) -> CumulocityApi:
         previously created instances are cached.
 
         Args:
-            headers (dict): A dictionarity of HTTP header entries. The user
+            headers (dict): A dictionary of HTTP header entries. The user
                 access is based on the Authorization header within.
 
         Returns:
@@ -101,15 +101,15 @@ class SimpleCumulocityApp(_CumulocityAppBase, CumulocityApi):
 
     The SimpleCumulocityApp class is intended to be used as base within
     a single-tenant micro service hosted on Cumulocity. It evaluates the
-    environment to teh resolve the authentication information automatically.
+    environment to the resolve the authentication information automatically.
 
     Note: This class should be used in Cumulocity micro services using the
     PER_TENANT authentication mode only. It will not function in environments
     using the MULTITENANT mode.
 
     The SimpleCumulocityApp class is an enhanced version of the standard
     CumulocityApi class. All Cumulocity functions can be used directly.
-    Additionally it can be used to provide CumulocityApi instances for
+    Additionally, it can be used to provide CumulocityApi instances for
     specific named users via the `get_user_instance` function.
     """
 
@@ -131,10 +131,16 @@ def __init__(self, application_key: str = None, cache_size: int = 100, cache_ttl
         """
         baseurl = self._get_env('C8Y_BASEURL')
         tenant_id = self._get_env('C8Y_TENANT')
-        username = self._get_env('C8Y_USER')
-        password = self._get_env('C8Y_PASSWORD')
+        # authentication is either token or username/password
+        try:
+            token = self._get_env('C8Y_TOKEN')
+            auth = HTTPBearerAuth(token)
+        except ValueError:
+            username = self._get_env('C8Y_USER')
+            password = self._get_env('C8Y_PASSWORD')
+            auth = HTTPBasicAuth(f'{tenant_id}/{username}', password)
         super().__init__(log=self._log, cache_size=cache_size, cache_ttl=cache_ttl,
-                         base_url=baseurl, tenant_id=tenant_id, auth=HTTPBasicAuth(f'{tenant_id}/{username}', password),
+                         base_url=baseurl, tenant_id=tenant_id, auth=auth,
                          application_key=application_key)
 
     def _build_user_instance(self, auth) -> CumulocityApi:
@@ -149,7 +155,7 @@ class MultiTenantCumulocityApp(_CumulocityAppBase):
 
     The MultiTenantCumulocityApp class is intended to be used as base within
     a multi-tenant micro service hosted on Cumulocity. It evaluates the
-    environment to teh resolve the bootstrap authentication information
+    environment to the resolve the bootstrap authentication information
     automatically.
 
     Note: This class is intended to be used in Cumulocity micro services
@@ -178,25 +184,42 @@ def _get_tenant_auth(self, tenant_id: str) -> AuthBase:
         try:
             return self._subscribed_auths[tenant_id]
         except KeyError:
-            self._subscribed_auths = self._read_subscriptions(self.bootstrap_instance)
+            self._subscribed_auths = self._read_subscription_auths(self.bootstrap_instance)
             return self._subscribed_auths[tenant_id]
 
     @classmethod
-    def _read_subscriptions(cls, bootstrap_instance: CumulocityApi):
+    def _read_subscriptions(cls, bootstrap_instance: CumulocityApi) -> list[dict]:
+        """Read subscribed tenants details.
+
+        Returns:
+            A list of tenant details dicts.
+        """
+        subscriptions = bootstrap_instance.get('/application/currentApplication/subscriptions')
+        return subscriptions['users']
+
+    @classmethod
+    def _read_subscription_auths(cls, bootstrap_instance: CumulocityApi):
         """Read subscribed tenant's auth information.
 
         Returns:
             A dict of tenant auth information by ID
         """
-        subscriptions = bootstrap_instance.get('/application/currentApplication/subscriptions')
         cache = {}
-        for subscription in subscriptions['users']:
+        for subscription in cls._read_subscriptions(bootstrap_instance):
             tenant = subscription['tenant']
             username = subscription['name']
             password = subscription['password']
             cache[tenant] = HTTPBasicAuth(f'{tenant}/{username}', password)
         return cache
 
+    def get_subscribers(self) -> list[str]:
+        """Query the subscribed tenants.
+
+        Returns:
+            A list of tenant ID.
+        """
+        return [x['tenant'] for x in self._read_subscriptions(self.bootstrap_instance)]
+
     @classmethod
     def _create_bootstrap_instance(cls) -> CumulocityApi:
         """Build the bootstrap instance from the environment."""

integration_tests/test_apps.py

@@ -0,0 +1,54 @@
+# Copyright (c) 2020 Software AG,
+# Darmstadt, Germany and/or Software AG USA Inc., Reston, VA, USA,
+# and/or its subsidiaries and/or its affiliates and/or their licensors.
+# Use, reproduction, transfer, publication or disclosure is prohibited except
+# as specifically provided for in your License Agreement with Software AG.
+
+import pytest
+import requests
+
+from c8y_api import CumulocityRestApi, HTTPBearerAuth
+from c8y_api.app import SimpleCumulocityApp
+from c8y_api.model import ManagedObject
+
+
+@pytest.fixture(name='token_app')
+def fix_token_app(test_environment):
+    """Provide a token-based REST API instance."""
+    # First, create an instance for basic auth
+    c8y = SimpleCumulocityApp()
+    # Submit auth request
+    form_data = {
+            'grant_type': 'PASSWORD',
+            'username': c8y.auth.username,
+            'password': c8y.auth.password
+        }
+    r = requests.post(url=c8y.base_url + '/tenant/oauth', data=form_data)
+    # Obtain token from response
+    assert r.status_code == 200
+    cookie = r.headers['Set-Cookie']
+    # split by ; to separate parts, then map a=b items to dictionary
+    cookie_parts = {x[0]:x[1] for x in [c.split('=') for c in cookie.split(';')] if len(x) == 2}
+    auth_token = cookie_parts['authorization']
+    assert auth_token
+    # build token-based app
+    return CumulocityRestApi(
+        base_url=c8y.base_url,
+        tenant_id=c8y.tenant_id,
+        auth=HTTPBearerAuth(auth_token)
+    )
+
+
+def test_token_based_app_headers(token_app):
+    """Verify that a token-based app only features a 'Bearer' auth header."""
+    response = token_app.session.get("https://httpbin.org/headers")
+    auth_header = response.json()['headers']['Authorization']
+    assert auth_header.startswith('Bearer')
+
+
+def test_token_based_app(token_app):
+    """Verify that a token-based app can be used for all kind of requests."""
+    mo = ManagedObject(token_app, name='test-object', type='test-object-type').create()
+    mo['new_Fragment'] = {}
+    mo.update()
+    mo.delete()

tests/test_app.py

@@ -127,10 +127,10 @@ def test_multi_tenant__caching_instances():
 
 @mock.patch.dict(os.environ, env_multi_tenant, clear=True)
 def test_multi_tenant__build_from_subscriptions():
-    """Verify that a uncached instance is build using the subscriptions."""
+    """Verify that an uncached instance is build using the subscriptions."""
     # pylint: disable=protected-access
 
-    with patch.object(MultiTenantCumulocityApp, '_read_subscriptions') as read_subscriptions:
+    with patch.object(MultiTenantCumulocityApp, '_read_subscription_auths') as read_subscriptions:
         # we mock _read_subscriptions so that we don't need an actual
         # connection and it returns what we want
         read_subscriptions.return_value = {'t12345': HTTPBasicAuth('username', 'password')}
@@ -195,7 +195,7 @@ def test_read_subscriptions():
 
         # we just need any CumulocityApi to do this call
         c8y = CumulocityApi(base_url=base_url, tenant_id=tenant_id, username=user, password=password)
-        subscriptions = MultiTenantCumulocityApp._read_subscriptions(c8y)
+        subscriptions = MultiTenantCumulocityApp._read_subscription_auths(c8y)
         # -> subscriptions were parsed correctly
         assert 't12345' in subscriptions
         assert 't54321' in subscriptions