added logging. Refactored WebServer a bit

app.py

@@ -28,3 +28,5 @@ if __name__ == '__main__':
     # start web server
     print('- start web server')
     web_server = WebServer(settings, database, jobs)
+
+    web_server.run()

pycs/frontend/WebServer.py

@@ -1,10 +1,14 @@
+import eventlet
+import socketio
+
 from glob import glob
-from os import path, getcwd
+from os import getcwd
+from os import path
 from os.path import exists
+from logging.config import dictConfig
 
-import eventlet
-import socketio
-from flask import Flask, send_from_directory
+from flask import Flask
+from flask import send_from_directory
 
 from pycs.database.Database import Database
 from pycs.frontend.endpoints.ListJobs import ListJobs
@@ -55,56 +59,30 @@ class WebServer:
 
     # pylint: disable=line-too-long
     def __init__(self, settings: dict, database: Database, jobs: JobRunner):
+
+        dictConfig(settings["logging"])
+
         # initialize web server
-        if exists('webui/index.html'):
-            print('production build')
-
-            # find static files and folders
-            static_files = {}
-
-            for file_path in glob('webui/*'):
-                file_path = file_path.replace('\\', '/')
-                static_files[file_path[5:]] = file_path
-
-            # separately add svg files and set their correct mime type
-            for svg_path in glob('webui/img/*.svg'):
-                svg_path = svg_path.replace('\\', '/')
-                static_files[svg_path[5:]] = {'content_type': 'image/svg+xml', 'filename': svg_path}
-
-            # create service objects
-            if len(settings['allowedOrigins']) > 0:
-                origins = settings['allowedOrigins']
-                self.__sio = socketio.Server(cors_allowed_origins=origins, async_mode='eventlet')
-            else:
-                self.__sio = socketio.Server(async_mode='eventlet')
-
-            self.__flask = Flask(__name__)
-            self.__app = socketio.WSGIApp(self.__sio, self.__flask, static_files=static_files)
-
-            # overwrite root path to serve index.html
-            @self.__flask.route('/', methods=['GET'])
-            def index():
-                # pylint: disable=unused-variable
-                return send_from_directory(path.join(getcwd(), 'webui'), 'index.html')
-
-        else:
-            print('development build')
-
-            # create service objects
-            self.__sio = socketio.Server(cors_allowed_origins='*', async_mode='eventlet')
-            self.__flask = Flask(__name__)
-            self.__app = socketio.WSGIApp(self.__sio, self.__flask)
-
-            # set access control header to allow requests from Vue.js development server
-            @self.__flask.after_request
-            def after_request(response):
-                # pylint: disable=unused-variable
-                response.headers['Access-Control-Allow-Origin'] = '*'
-                return response
+        self.__flask = Flask(__name__)
+
+        init_func = self.production_init if exists('webui/index.html') else self.development_init
+        kwargs, static_files = init_func()
+
+        self.__sio = socketio.Server(**kwargs)
+        self.__app = socketio.WSGIApp(self.__sio, self.__flask, static_files=static_files)
+        self.__host, self.__port = settings['host'], settings['port']
 
         # set json encoder so database objects are serialized correctly
         self.__flask.json_encoder = JSONEncoder
 
+        notifications = self.init_notifications(jobs)
+        self.define_routes(database, jobs, notifications)
+
+    @property
+    def logger(self):
+        return self.__flask.logger
+
+    def init_notifications(self, jobs):
         # create notification manager
         notifications = NotificationManager(self.__sio)
 
@@ -114,6 +92,55 @@ class WebServer:
         jobs.on_finish(notifications.edit_job)
         jobs.on_remove(notifications.remove_job)
 
+        return notifications
+
+    def development_init(self):
+
+        self.logger.info('development build')
+
+        # set access control header to allow requests from Vue.js development server
+        @self.__flask.after_request
+        def after_request(response):
+            # pylint: disable=unused-variable
+            response.headers['Access-Control-Allow-Origin'] = '*'
+            return response
+
+        return dict(cors_allowed_origins='*', async_mode='eventlet'), None
+
+    def production_init(self):
+
+        self.logger.info('production build')
+
+        kwargs = dict(async_mode='eventlet')
+        if len(settings['allowedOrigins']) > 0:
+            origins = settings['allowedOrigins']
+            kwargs["cors_allowed_origins"] = origins
+
+        # overwrite root path to serve index.html
+        @self.__flask.route('/', methods=['GET'])
+        def index():
+            # pylint: disable=unused-variable
+            return send_from_directory(path.join(getcwd(), 'webui'), 'index.html')
+
+        return kwargs, self.static_files
+
+    @property
+    def static_files(self) -> dict:
+        # find static files and folders
+        static_files = {}
+
+        for file_path in glob('webui/*'):
+            file_path = file_path.replace('\\', '/')
+            static_files[file_path[5:]] = file_path
+
+        # separately add svg files and set their correct mime type
+        for svg_path in glob('webui/img/*.svg'):
+            svg_path = svg_path.replace('\\', '/')
+            static_files[svg_path[5:]] = {'content_type': 'image/svg+xml', 'filename': svg_path}
+
+        return static_files
+
+    def define_routes(self, database, jobs, notifications):
         # additional
         self.__flask.add_url_rule(
             '/folder',
@@ -280,5 +307,5 @@ class WebServer:
             view_func=PredictFile.as_view('predict_file', database, notifications, jobs)
         )
 
-        # finally start web server
-        eventlet.wsgi.server(eventlet.listen((settings['host'], settings['port'])), self.__app)
+    def run(self):
+        eventlet.wsgi.server(eventlet.listen((self.__host, self.__port)), self.__app)

settings.json

@@ -1,5 +1,25 @@
 {
   "host": "",
   "port": 5000,
-  "allowedOrigins": []
+  "allowedOrigins": [],
+
+  "logging": {
+    "version": 1,
+    "formatters": {
+      "default": {
+        "format": "[%(asctime)s] %(levelname)s in %(module)s: %(message)s"
+      }
+    },
+    "handlers": {
+      "wsgi": {
+        "class": "logging.StreamHandler",
+        "stream": "ext://flask.logging.wsgi_errors_stream",
+        "formatter": "default"
+      }
+    },
+    "root": {
+        "level": "INFO",
+        "handlers": ["wsgi"]
+    }
+  }
 }