Localize notification_utils to the API

This changeset pulls in all of the notification_utils code directly into the API and removes it as an external dependency.  We are doing this to cut down on operational maintenance of the project and will begin removing parts of it no longer needed for the API.

Signed-off-by: Carlo Costino <carlo.costino@gsa.gov>

notifications_utils/clients/antivirus/antivirus_client.py

@@ -0,0 +1,55 @@
+import requests
+from flask import current_app
+
+
+class AntivirusError(Exception):
+    def __init__(self, message=None, status_code=None):
+        self.message = message
+        self.status_code = status_code
+
+    @classmethod
+    def from_exception(cls, e):
+        try:
+            message = e.response.json()["error"]
+            status_code = e.response.status_code
+        except (TypeError, ValueError, AttributeError, KeyError):
+            message = "connection error"
+            status_code = 503
+
+        return cls(message, status_code)
+
+
+class AntivirusClient:
+    def __init__(self, api_host=None, auth_token=None):
+        self.api_host = api_host
+        self.auth_token = auth_token
+
+    def init_app(self, app):
+        self.api_host = app.config["ANTIVIRUS_API_HOST"]
+        self.auth_token = app.config["ANTIVIRUS_API_KEY"]
+
+    def scan(self, document_stream):
+        try:
+            response = requests.post(
+                "{}/scan".format(self.api_host),
+                headers={
+                    "Authorization": "Bearer {}".format(self.auth_token),
+                },
+                files={"document": document_stream},
+            )
+
+            response.raise_for_status()
+
+        except requests.RequestException as e:
+            error = AntivirusError.from_exception(e)
+            current_app.logger.warning(
+                "Notify Antivirus API request failed with error: {}".format(
+                    error.message
+                )
+            )
+
+            raise error
+        finally:
+            document_stream.seek(0)
+
+        return response.json()["ok"]