Add internet connection check and rewrite some parts

Scripts/resource_fetcher.py

@@ -1,8 +1,8 @@
-import sys
-import ssl
 import os
-import plistlib
 import json
+import plistlib
+import socket
+import sys
 
 if sys.version_info >= (3, 0):
     from urllib.request import urlopen, Request
@@ -11,26 +11,17 @@ else:
     from urllib2 import urlopen, Request
 
 class ResourceFetcher:
-    def __init__(self, headers=None):
+    def __init__(self, headers={}):
         self.request_headers = headers
         self.buffer_size = 16 * 1024
-        self.ssl_context = self.create_ssl_context()
 
-    def create_ssl_context(self):
-        try:
-            cafile = ssl.get_default_verify_paths().openssl_cafile
-            if not os.path.exists(cafile):
-                import certifi
-                cafile = certifi.where()
-            ssl_context = ssl.create_default_context(cafile=cafile)
-        except Exception as e:
-            print("SSL Context Creation Error: {}".format(e))
-            ssl_context = ssl._create_unverified_context()
-        return ssl_context
+    def is_connected(self, timeout=5):
+        socket.create_connection(("github.com", 443), timeout=timeout)
 
     def fetch_and_parse_content(self, resource_url, content_type=None):
-        request = Request(resource_url, headers=self.request_headers or {})
-        with urlopen(request, context=self.ssl_context) as response:
+        self.is_connected()
+
+        with urlopen(resource_url) as response:
             content = response.read()
             if content_type == 'json':
                 return json.loads(content)
@@ -39,19 +30,31 @@ class ResourceFetcher:
             else:
                 return content.decode('utf-8')
 
-    def download_and_save_file(self, resource_url, destination_path):
-        request = Request(resource_url, headers=self.request_headers or {})
-        with urlopen(request, context=self.ssl_context) as response:
-            total_size = response.length
-            bytes_downloaded = 0
-            print("Download from {}".format(resource_url))
+    def _download_with_progress(self, response, local_file):
+        total_size = response.getheader('Content-Length')
+        if total_size:
+            total_size = int(total_size)
+        bytes_downloaded = 0
 
-            with open(destination_path, 'wb') as file_writer:
-                while True:
-                    chunk = response.read(self.buffer_size)
-                    if not chunk:
-                        break
-                    file_writer.write(chunk)
-                    bytes_downloaded += len(chunk)
-                    if total_size:
-                        print("Downloaded {:.2f} MB of {:.2f} MB".format(bytes_downloaded / (1024 * 1024), total_size / (1024 * 1024)), end='\r')
+        while True:
+            chunk = response.read(self.buffer_size)
+            if not chunk:
+                break
+            local_file.write(chunk)
+            bytes_downloaded += len(chunk)
+
+            if total_size:
+                percent = int(bytes_downloaded / total_size * 100)
+                progress = f"[{'=' * (percent // 2):50s}] {percent}%  {bytes_downloaded / (1024 * 1024):.2f}/{total_size / (1024 * 1024):.2f} MB"
+            else:
+                progress = f"Downloaded {bytes_downloaded / (1024 * 1024):.2f} MB"
+            print(progress, end='\r')
+
+        print()
+
+    def download_and_save_file(self, resource_url, destination_path):
+        self.is_connected()
+
+        with urlopen(resource_url) as response, open(destination_path, 'wb') as local_file:
+            print(f"Downloading from {resource_url}")
+            self._download_with_progress(response, local_file)