Rework API and add Dummy drivers (#18)

Author: maretskiy

etc/config.json

@@ -10,15 +10,26 @@
     },
     "notify_backends": {
         "sf": {
-          "salesforce": {
-            "atuh_url": "https://somedomain.my.salesforce.com",
-            "username": "babalbalba",
-            "password": "abablabal",
-            "environment": "what?",
-            "client_id":  "...",
-            "client_secret": "...",
-            "organization_id": "...."
-          }
-       }
+            "sfdc": {
+                "atuh_url": "https://somedomain.my.salesforce.com",
+                "username": "foo_username",
+                "password": "foo_pa55w0rd",
+                "organization_id": "mycorp",
+                "environment": "fooenv",
+                "client_id":  "",
+                "client_secret": ""
+            }
+        },
+        "dummy": {
+            "dummy_pass": {},
+            "dummy_fail": {}
+        },
+        "dummyrand": {
+            "dummy_random": {"probability": 0.5}
+        },
+        "dummyerr": {
+            "dummy_err": {},
+            "dummy_err_explained": {}
+        }
     }
 }

notify/api/v1/api.py

@@ -13,14 +13,13 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import json
+import hashlib
 import logging
 
 import flask
-import jsonschema
 
 from notify import config
-from notify.drivers import driver
+from notify import driver
 
 
 LOG = logging.getLogger("api")
@@ -30,110 +29,75 @@
 bp = flask.Blueprint("notify", __name__)
 
 
-PAYLOAD_SCHEMA = {
-    "type": "object",
-    "$schema": "http://json-schema.org/draft-04/schema",
-
-    "properties": {
-        "region": {
-            "type": "string"
-        },
-        "description": {
-            "type": "string"
-        },
-        "severity": {
-            "enum": ["OK", "INFO", "UNKNOWN", "WARNING", "CRITICAL", "DOWN"]
-        },
-        "who": {
-            "type": "array",
-            "items": {
-                "type": "string"
-            },
-            "minItems": 1,
-            "uniqueItems": True
-        },
-        "what": {
-            "type": "string"
-        }
-    },
-    "required": ["description", "region", "severity", "who", "what"],
-    "additionalProperties": False
-}
-
-
-# NOTE(boris-42): Use here pool of resources
 CACHE = {}
 
 
+def make_hash(dct):
+    """Generate MD5 hash of given dict.
+
+    :param dct: dict to hash. There may be collisions
+                if it isn't flat (includes sub-dicts)
+    :returns: str MD5 hexdigest (32 chars)
+    """
+    str_repr = "|".join(["%s:%s" % x for x in sorted(dct.items())])
+    return hashlib.md5(str_repr.encode("utf-8")).hexdigest()
+
+
 @bp.route("/notify/<backends>", methods=["POST"])
 def send_notification(backends):
     global CACHE
 
+    backends = set(backends.split(","))
+    payload = flask.request.get_json(force=True, silent=True)
+
+    if not payload:
+        return flask.jsonify({"error": "Missed Payload"}), 400
+
     try:
-        content = json.loads(flask.request.form['payload'])
-        jsonschema.validate(content, PAYLOAD_SCHEMA)
-    except Exception as e:
-        return flask.jsonify({
-            "errors": True,
-            "status": 400,
-            "description": "Wrong payload: %s" % str(e),
-            "results": []
-        }), 400
-
-    conf = config.get_config()
-    resp = {
-        "errors": False,
-        "status": 200,
-        "description": "",
-        "results": []
-    }
-
-    for backend in backends.split(","):
-        result = {
-            "backend": backend,
-            "status": 200,
-            "errors": False,
-            "description": "",
-            "results": []
-        }
-        if backend in conf["notify_backends"]:
-            for dr, driver_cfg in conf["notify_backends"][backend].items():
-                r = {
-                    "backend": backend,
-                    "driver": dr,
-                    "error": False,
-                    "status": 200
-                }
-                try:
-
-                    driver_key = "%s.%s" % (backend, dr)
-                    if driver_key not in CACHE:
-                        # NOTE(boris-42): We should use here pool with locks
-                        CACHE[driver_key] = driver.get_driver(dr)(driver_cfg)
-
-                    # NOTE(boris-42): It would be smarter to call all drivers
-                    #                 notify in parallel
-                    CACHE[driver_key].notify(content)
-
-                except Exception as e:
-                    print(e)
-                    r["status"] = 500
-                    r["error"] = True
-                    resp["errors"] = True
-                    result["errors"] = True
-                    r["description"] = ("Something went wrong %s.%s"
-                                        % (backend, dr))
-
-                result["results"].append(r)
-        else:
-            result["status"] = 404
-            result["errors"] = True
-            resp["errors"] = True
-            result["description"] = "Backend %s not found" % backend
-
-        resp["results"].append(result)
-
-    return flask.jsonify(resp), resp["status"]
+        driver.Driver.validate_payload(payload)
+    except ValueError as e:
+        return flask.jsonify({"error": "Bad Payload: {}".format(e)}), 400
+
+    notify_backends = config.get_config()["notify_backends"]
+
+    unexpected = backends - set(notify_backends)
+    if unexpected:
+        mesg = "Unexpected backends: {}".format(", ".join(unexpected))
+        return flask.jsonify({"error": mesg}), 400
+
+    result = {"payload": payload, "result": {},
+              "total": 0, "passed": 0, "failed": 0, "errors": 0}
+
+    for backend in backends:
+        for drv_name, drv_conf in notify_backends[backend].items():
+
+            key = "{}.{}".format(drv_name, make_hash(drv_conf))
+            if key not in CACHE:
+                CACHE[key] = driver.get_driver(drv_name, drv_conf)
+            driver_ins = CACHE[key]
+
+            result["total"] += 1
+            if backend not in result["result"]:
+                result["result"][backend] = {}
+
+            # TODO(maretskiy): run in parallel
+            try:
+                status = driver_ins.notify(payload)
+
+                result["passed"] += status
+                result["failed"] += not status
+                result["result"][backend][drv_name] = {"status": status}
+            except driver.ExplainedError as e:
+                result["result"][backend][drv_name] = {"error": str(e)}
+                result["errors"] += 1
+            except Exception as e:
+                LOG.error(("Backend '{}' driver '{}' "
+                           "error: {}").format(backend, drv_name, e))
+                error = "Something has went wrong!"
+                result["result"][backend][drv_name] = {"error": error}
+                result["errors"] += 1
+
+    return flask.jsonify(result), 200
 
 
 def get_blueprints():

notify/driver.py

@@ -0,0 +1,124 @@
+# Copyright 2016: Mirantis Inc.
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import importlib
+import logging
+
+import jsonschema
+
+
+DRIVERS = {}
+
+
+def get_driver(name, conf):
+    """Get driver by name.
+
+    :param name: driver name
+    :param conf: dict, driver configuration
+    :rtype: Driver
+    :raises: RuntimeError
+    """
+    global DRIVERS
+    if name not in DRIVERS:
+        try:
+            module = importlib.import_module("notify.drivers." + name)
+            DRIVERS[name] = module.Driver
+        except (ImportError, AttributeError):
+            mesg = "Unexpected driver: '{}'".format(name)
+            logging.error(mesg)
+            raise RuntimeError(mesg)
+
+    driver_cls = DRIVERS[name]
+
+    try:
+        driver_cls.validate_config(conf)
+    except ValueError as e:
+        mesg = "Bad configuration for driver '{}'".format(name)
+        logging.error("{}: {}".format(mesg, e))
+        raise RuntimeError(mesg)
+
+    return driver_cls(conf)
+
+
+class ExplainedError(Exception):
+    """Error that should be delivered to end user."""
+
+
+class Driver(object):
+    """Base for notification drivers."""
+
+    PAYLOAD_SCHEMA = {
+        "$schema": "http://json-schema.org/draft-04/schema",
+        "type": "object",
+        "properties": {
+            "region": {"type": "string"},
+            "description": {"type": "string"},
+            "severity": {
+                "enum": ["OK", "INFO", "UNKNOWN", "WARNING",
+                         "CRITICAL", "DOWN"]},
+            "who": {"type": "array",
+                    "items": {"type": "string"},
+                    "minItems": 1,
+                    "uniqueItems": True},
+            "what": {"type": "string"},
+            "affected_hosts": {"type": "array"}
+        },
+        "required": ["region", "description", "severity", "who", "what"],
+        "additionalProperties": False
+    }
+
+    CONFIG_SCHEMA = {
+        "$schema": "http://json-schema.org/draft-04/schema",
+        "type": "object"
+    }
+
+    @classmethod
+    def validate_payload(cls, payload):
+        """Payload validation.
+
+        :param payload: notification payload
+        :raises: ValueError
+        """
+        try:
+            jsonschema.validate(payload, cls.PAYLOAD_SCHEMA)
+        except jsonschema.exceptions.ValidationError as e:
+            raise ValueError(str(e))
+
+    @classmethod
+    def validate_config(cls, conf):
+        """Driver configuration validation.
+
+        :param conf: driver configuration
+        :raises: ValueError
+        """
+        try:
+            jsonschema.validate(conf, cls.CONFIG_SCHEMA)
+        except jsonschema.exceptions.ValidationError as e:
+            raise ValueError(str(e))
+
+    def __init__(self, config):
+        self.config = config
+
+    def notify(self, payload):
+        """Send notification alert.
+
+        This method must be overriden by specific driver implementation.
+
+        :param payload: alert data
+        :type payload: dict, validated api.PAYLOAD_SCHEMA
+        :returns: status whether notification is successful
+        :rtype: bool
+        """
+        raise NotImplementedError()

notify/drivers/driver.py notify/drivers/dummy_err.pynotify/drivers/driver.py renamed to notify/drivers/dummy_err.py

@@ -1,4 +1,3 @@
-
 # Copyright 2016: Mirantis Inc.
 # All Rights Reserved.
 #
@@ -14,23 +13,11 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import importlib
-import logging
-
-
-def get_driver(driver_type):
-    try:
-        return importlib.import_module("." + driver_type + ".driver",
-                                       "notify.drivers").Driver
-    except ImportError:
-        logging.error("Could not load driver for '{}'".format(driver_type))
-        raise
-
+from notify import driver
 
-class Driver(object):
 
-    def __init__(self, config):
-        self.config = config
+class Driver(driver.Driver):
+    """Simulate unexpected error by raising ValueError."""
 
-    def notify(self):
-        raise NotImplemented()
+    def notify(self, payload):
+        raise ValueError("This error message is for logging only!")