Updated type hinting (#167)

* Updated type hinting

* Fix lint

Author: avara1986

pyms/config/resource.py

@@ -1,9 +1,11 @@
+from typing import Text
+
 from pyms.config import get_conf
 
 
 class ConfigResource:
 
-    config_resource = None
+    config_resource: Text = ""
 
     def __init__(self, *args, **kwargs):
         self.config = get_conf(service=self.config_resource, empty_init=True, uppercase=False, *args, **kwargs)

pyms/flask/app/create_app.py

@@ -1,6 +1,6 @@
 import logging
 import os
-from typing import Text
+from typing import List
 
 from flask import Flask
 
@@ -10,7 +10,7 @@
 from pyms.crypt.driver import CryptResource
 from pyms.flask.app.utils import SingletonMeta, ReverseProxied
 from pyms.flask.healthcheck import healthcheck_blueprint
-from pyms.flask.services.driver import ServicesResource
+from pyms.flask.services.driver import ServicesResource, DriverService
 from pyms.logger import CustomJsonFormatter
 from pyms.utils import check_package_exists, import_from
 
@@ -72,11 +72,12 @@ def example():
     Current services are swagger, request, tracer, metrics
     """
     config_resource = CONFIG_BASE
-    services = []
-    application = None
-    swagger = False
-    request = False
-    tracer = False
+    services: List[DriverService] = []
+    application = Flask
+    swagger: DriverService = None
+    request: DriverService = None
+    tracer: DriverService = None
+    metrics: DriverService = None
     _singleton = True
 
     def __init__(self, *args, **kwargs):
@@ -137,7 +138,7 @@ def init_tracer(self) -> None:
         """Set attribute in flask `tracer`. See in `pyms.flask.services.tracer` how it works
         :return: None
         """
-        if self._exists_service("tracer"):
+        if self.tracer:
             FlaskTracing = import_from("flask_opentracing", "FlaskTracing")
             client = self.tracer.get_client()
             self.application.tracer = FlaskTracing(client, True, self.application)
@@ -169,7 +170,7 @@ def init_app(self) -> Flask:
         run a "normal" Flask app.
         :return: None
         """
-        if self._exists_service("swagger"):
+        if self.swagger:
             application = self.swagger.init_app(config=self.config.to_flask(), path=self.path)
         else:
             check_package_exists("flask")
@@ -183,11 +184,11 @@ def init_app(self) -> Flask:
 
         return application
 
-    def init_metrics(self):
+    def init_metrics(self) -> None:
         """Set attribute in flask `metrics`. See in `pyms.flask.services.metrics` how it works
         :return: None
         """
-        if getattr(self, "metrics", False) and self.metrics:
+        if self.metrics:
             self.application.register_blueprint(self.metrics.metrics_blueprint)
             self.metrics.add_logger_handler(
                 self.application.logger,
@@ -231,14 +232,6 @@ def create_app(self):
 
         return self.application
 
-    def _exists_service(self, service_name: Text) -> bool:
-        """Check if service exists in the config.yml file
-        :param service_name:
-        :return: bool
-        """
-        service = getattr(self, service_name, False)
-        return service and service is not None
-
     def add_error_handlers(self):
         """Subclasses will override this method in order to add specific error handlers. This should be done with
         calls to add_error_handler method.

pyms/flask/app/utils.py

@@ -1,10 +1,13 @@
+from typing import Dict
+
+
 class SingletonMeta(type):
     """
     The Singleton class can be implemented in different ways in Python. Some
     possible methods include: base class, decorator, metaclass. We will use the
     metaclass because it is best suited for this purpose.
     """
-    _instances = {}
+    _instances: Dict[type, type] = {}
     _singleton = True
 
     def __call__(cls, *args, **kwargs):

pyms/flask/services/driver.py

@@ -1,5 +1,5 @@
 import logging
-from typing import Text, Tuple
+from typing import Text, Tuple, Iterator
 
 from pyms.config import ConfFile
 from pyms.config.resource import ConfigResource
@@ -61,7 +61,7 @@ class ServicesResource(ConfigResource):
     """
     config_resource = SERVICE_BASE
 
-    def get_services(self) -> Tuple[Text, DriverService]:
+    def get_services(self) -> Iterator[Tuple[Text, DriverService]]:
         for k in self.config.__dict__.keys():
             if k.islower() and not k.startswith("_"):
                 service = self.get_service(k)

pyms/flask/services/metrics.py

@@ -1,5 +1,6 @@
 import time
 import logging
+from typing import Text
 
 from flask import Blueprint, Response, request
 from prometheus_client import Counter, Histogram, generate_latest
@@ -45,7 +46,7 @@ class Service(DriverService):
     """
     Adds [Prometheus](https://prometheus.io/) metrics using the [Prometheus Client Library](https://github.com/prometheus/client_python).
     """
-    config_resource = "metrics"
+    config_resource: Text = "metrics"
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)

setup.py

@@ -34,7 +34,6 @@
     'requests>=2.24.0',
 ]
 install_swagger_requires = [
-    'swagger-ui-bundle>=0.0.2',
     'connexion[swagger-ui]>=2.7.0',
     'swagger-ui-bundle>=0.0.6',
     'semver>=2.10.1',

tests/test_flask.py

@@ -68,11 +68,6 @@ def test_swagger(self):
     def test_exists_service(self):
         self.assertTrue(isinstance(self.app.ms.swagger, DriverService))
 
-    def test_disabled_service(self):
-        with pytest.raises(AttributeError) as excinfo:
-            self.assertTrue(isinstance(self.app.ms.metrics, DriverService))
-        assert "'MyMicroservice' object has no attribute 'metrics'" in str(excinfo.value)
-
     def test_reverse_proxy(self):
         response = self.client.get('/my-proxy-path/ui/', headers={"X-Script-Name": "/my-proxy-path"})
         self.assertEqual(200, response.status_code)