add ForemanApi

apypie/__init__.py

@@ -11,5 +11,6 @@
 from apypie.example import Example
 from apypie.param import Param
 from apypie.inflector import Inflector
+from apypie.foreman import ForemanApi, ForemanApiException
 
-__all__ = ['Api', 'Resource', 'Route', 'Action', 'Example', 'Param', 'Inflector']
+__all__ = ['Api', 'Resource', 'Route', 'Action', 'Example', 'Param', 'Inflector', 'ForemanApi', 'ForemanApiException']

apypie/foreman.py

@@ -0,0 +1,239 @@
+"""
+Apypie Foreman module
+
+opinionated helpers to use Apypie with Foreman
+"""
+import time
+
+from apypie.api import Api
+
+PER_PAGE = 2 << 31
+
+
+class ForemanApiException(Exception):
+    """
+    General Exception, raised by any issue in ForemanApi
+    """
+
+    def __init__(self, msg, error=None):
+        self.msg = msg
+        self.error = error
+        super().__init__()
+
+    def __repr__(self):
+        return str(self)
+
+    def __str__(self):
+        string = f'{self.__class__.__name__}: {self.msg}'
+        if self.error:
+            string += f' - {self.error}'
+        return string
+
+    @classmethod
+    def from_exception(cls, exc, msg):
+        """
+        Create a ForemanException from any other Exception
+
+        Especially useful to gather the error message from HTTP responses.
+        """
+        error = None
+        if hasattr(exc, 'response'):
+            try:
+                response = exc.response.json()
+                if 'error' in response:
+                    error = response['error']
+                else:
+                    error = response
+            except Exception:  # pylint: disable=broad-except
+                error = exc.response.text
+        return cls(msg=msg, error=error)
+
+
+class ForemanApi(Api):
+    """
+    apypie.Api with default settings and helper functions for Foreman
+    """
+
+    def __init__(self, **kwargs):
+        self.task_timeout = kwargs.pop('task_timeout', 60)
+        self.task_poll = 4
+        kwargs['api_version'] = 2
+        super().__init__(**kwargs)
+
+    def _resource(self, resource):
+        if resource not in self.resources:
+            raise ForemanApiException(msg="The server doesn't know about {0}, is the right plugin installed?".format(resource))
+        return self.resource(resource)
+
+    def _resource_call(self, resource, *args, **kwargs):
+        return self._resource(resource).call(*args, **kwargs)
+
+    def _resource_prepare_params(self, resource, action, params):
+        api_action = self._resource(resource).action(action)
+        return api_action.prepare_params(params)
+
+    def resource_action(self, resource, action, params, options=None, data=None, files=None,  # pylint: disable=too-many-arguments
+                        ignore_task_errors=False):
+        """
+        Perform a generic action on a resource
+
+        Will wait for tasks if the action returns one
+        """
+        resource_payload = self._resource_prepare_params(resource, action, params)
+        if options is None:
+            options = {}
+        try:
+            result = self._resource_call(resource, action, resource_payload, options=options, data=data, files=files)
+            is_foreman_task = isinstance(result, dict) and 'action' in result and 'state' in result and 'started_at' in result
+            if is_foreman_task:
+                result = self.wait_for_task(result, ignore_errors=ignore_task_errors)
+        except Exception as exc:
+            msg = 'Error while performing {0} on {1}: {2}'.format(
+                action, resource, str(exc))
+            raise ForemanApiException.from_exception(exc, msg) from exc
+        return result
+
+    def wait_for_task(self, task, ignore_errors=False):
+        """
+        Wait for a foreman-tasks task, polling it every ``self.task_poll`` seconds.
+
+        Will raise a ForemanApiException when task has not finished in ``self.task_timeout`` seconds.
+        """
+        duration = self.task_timeout
+        while task['state'] not in ['paused', 'stopped']:
+            duration -= self.task_poll
+            if duration <= 0:
+                raise ForemanApiException(msg="Timeout waiting for Task {0}".format(task['id']))
+            time.sleep(self.task_poll)
+
+            resource_payload = self._resource_prepare_params('foreman_tasks', 'show', {'id': task['id']})
+            task = self._resource_call('foreman_tasks', 'show', resource_payload)
+        if not ignore_errors and task['result'] != 'success':
+            msg = 'Task {0}({1}) did not succeed. Task information: {2}'.format(task['action'], task['id'], task['humanized']['errors'])
+            raise ForemanApiException(msg=msg)
+        return task
+
+    def show(self, resource, resource_id, params=None):
+        """
+        Execute the ``show`` action on an entity.
+
+        :param resource: Plural name of the api resource to show
+        :type resource: str
+        :param resource_id: The ID of the entity to show
+        :type resource_id: int
+        :param params: Lookup parameters (i.e. parent_id for nested entities)
+        :type params: Union[dict,None], optional
+        """
+        payload = {'id': resource_id}
+        if params:
+            payload.update(params)
+        return self.resource_action(resource, 'show', payload)
+
+    def list(self, resource, search=None, params=None):
+        """
+        Execute the ``index`` action on an resource.
+
+        :param resource: Plural name of the api resource to show
+        :type resource: str
+        :param search: Search string as accepted by the API to limit the results
+        :type search: str, optional
+        :param params: Lookup parameters (i.e. parent_id for nested entities)
+        :type params: Union[dict,None], optional
+        """
+        payload = {'per_page': PER_PAGE}
+        if search is not None:
+            payload['search'] = search
+        if params:
+            payload.update(params)
+
+        return self.resource_action(resource, 'index', payload)['results']
+
+    def create(self, resource, desired_entity, params=None):
+        """
+        Create entity with given properties
+
+        :param resource: Plural name of the api resource to manipulate
+        :type resource: str
+        :param desired_entity: Desired properties of the entity
+        :type desired_entity: dict
+        :param params: Lookup parameters (i.e. parent_id for nested entities)
+        :type params: dict, optional
+
+        :return: The new current state of the entity
+        :rtype: dict
+        """
+        payload = desired_entity.copy()
+        if params:
+            payload.update(params)
+        return self.resource_action(resource, 'create', payload)
+
+    def update(self, resource, desired_entity, params=None):
+        """
+        Update entity with given properties
+
+        :param resource: Plural name of the api resource to manipulate
+        :type resource: str
+        :param desired_entity: Desired properties of the entity
+        :type desired_entity: dict
+        :param params: Lookup parameters (i.e. parent_id for nested entities)
+        :type params: dict, optional
+
+        :return: The new current state of the entity
+        :rtype: dict
+        """
+        payload = desired_entity.copy()
+        if params:
+            payload.update(params)
+        return self.resource_action(resource, 'update', payload)
+
+    def delete(self, resource, current_entity, params=None):
+        """
+        Delete a given entity
+
+        :param resource: Plural name of the api resource to manipulate
+        :type resource: str
+        :param current_entity: Current properties of the entity
+        :type current_entity: dict
+        :param params: Lookup parameters (i.e. parent_id for nested entities)
+        :type params: dict, optional
+
+        :return: The new current state of the entity
+        :rtype: Union[dict,None]
+        """
+        payload = {'id': current_entity['id']}
+        if params:
+            payload.update(params)
+        entity = self.resource_action(resource, 'destroy', payload)
+
+        # this is a workaround for https://projects.theforeman.org/issues/26937
+        if entity and isinstance(entity, dict) and 'error' in entity and 'message' in entity['error']:
+            raise ForemanApiException(msg=entity['error']['message'])
+
+        return None  # pylint: disable=useless-return
+
+    def validate_payload(self, resource, action, payload):
+        """
+        Check whether the payload only contains supported keys.
+
+        :param resource: Plural name of the api resource to check
+        :type resource: str
+        :param action: Name of the action to check payload against
+        :type action: str
+        :param payload: API paylod to be checked
+        :type payload: dict
+
+        :return: The payload as it can be submitted to the API and set of unssuported parameters
+        :rtype: tuple(dict, set)
+        """
+        filtered_payload = self._resource_prepare_params(resource, action, payload)
+        unsupported_parameters = set(payload.keys()) - set(_recursive_dict_keys(filtered_payload))
+        return (filtered_payload, unsupported_parameters)
+
+
+def _recursive_dict_keys(a_dict):
+    """Find all keys of a nested dictionary"""
+    keys = set(a_dict.keys())
+    for _k, value in a_dict.items():
+        if isinstance(value, dict):
+            keys.update(_recursive_dict_keys(value))
+    return keys

tests/test_foreman.py

@@ -0,0 +1,7 @@
+from apypie.foreman import _recursive_dict_keys
+
+
+def test_recursive_dict_keys():
+    a_dict = {'level1': 'has value', 'level2': {'real_level2': 'more value', 'level3': {'real_level3': 'nope'}}}
+    expected_keys = set(['level1', 'level2', 'level3', 'real_level2', 'real_level3'])
+    assert _recursive_dict_keys(a_dict) == expected_keys