network_handler.py: Initial implementation

resources/network_handler.py

@@ -0,0 +1,150 @@
+# Download files from the network
+# Implements an object, where other libraries can use to query download status
+
+import time
+import requests
+import threading
+import logging
+from pathlib import Path
+
+from resources import utilities
+
+
+SESSION = requests.Session()
+
+class network_utilities:
+
+    def __init__(self, url):
+        self.url: str = url
+
+
+    def verify_network_connection(self):
+        try:
+            response = requests.head(self.url, timeout=5, allow_redirects=True)
+            return True
+        except (
+            requests.exceptions.Timeout,
+            requests.exceptions.TooManyRedirects,
+            requests.exceptions.ConnectionError,
+            requests.exceptions.HTTPError
+        ):
+            return False
+
+
+class download_object:
+
+    def __init__(self, url):
+        self.url:       str = url
+        self.status:    str = "Downloading"
+        self.error_msg: str = ""
+        self.filename:  str = self._get_filename()
+
+        self.total_file_size:      float = 0.0
+        self.downloaded_file_size: float = 0.0
+        self.start_time:           float = time.time()
+
+        self.error:             bool = False
+        self.should_stop:       bool = False
+        self.has_network:       bool = network_utilities(self.url).verify_network_connection()
+        self.download_complete: bool = False
+
+        self.active_thread: threading.Thread = None
+
+        if self.has_network:
+            self._populate_file_size()
+
+
+    def __del__(self):
+        self.stop()
+
+
+    def download(self, path, display_progress=False):
+        if self.active_thread:
+            return
+        logging.info(f"Starting download: {self.filename}")
+        self.active_thread = threading.Thread(target=self._download, args=(path,display_progress,))
+        self.active_thread.start()
+
+
+    def _get_filename(self):
+        return Path(self.url).name
+
+
+    def _populate_file_size(self):
+        try:
+            self.total_file_size = int(requests.head(self.url, allow_redirects=True, timeout=5).headers['Content-Length'])
+        except Exception as e:
+            self.error = True
+            self.error_msg = str(e)
+            self.status = "Error"
+            logging.error(f"Error determining file size {self.url}: {self.error_msg}")
+
+
+    def _prepare_working_directory(self, path):
+        if Path(path).exists():
+            Path(path).unlink()
+
+
+    def _download(self, path, display_progress=False):
+        try:
+            if not self.has_network:
+                raise Exception("No network connection")
+
+            self._prepare_working_directory(path)
+
+            response = SESSION.get(self.url, stream=True)
+
+            with open(path, 'wb') as file:
+                for i, chunk in enumerate(response.iter_content(1024 * 1024 * 4)):
+                    if self.should_stop:
+                        raise Exception("Download stopped")
+                    if chunk:
+                        file.write(chunk)
+                        self.downloaded_file_size += len(chunk)
+                        if display_progress and i % 100:
+                            print(f"Downloaded {self.get_percent():.2f}% of {self.filename} ({utilities.human_fmt(self.get_speed())}/s) ({self.get_time_remaining():.2f} seconds remaining)")
+                self.download_complete = True
+                logging.info(f"Download complete: {self.filename}")
+        except Exception as e:
+            self.error = True
+            self.error_msg = str(e)
+            self.status = "Error"
+            logging.error(f"Error downloading {self.url}: {self.error_msg}")
+        self.status = "Done"
+
+
+    def get_percent(self):
+        if self.total_file_size == 0:
+            logging.error("File size is 0, cannot calculate percent")
+            return -1
+        return self.downloaded_file_size / self.total_file_size * 100
+
+
+    def get_speed(self):
+        return self.downloaded_file_size / (time.time() - self.start_time)
+
+
+    def get_time_remaining(self):
+        if self.total_file_size == 0:
+            logging.error("File size is 0, cannot calculate time remaining")
+            return -1
+        return (self.total_file_size - self.downloaded_file_size) / self.get_speed()
+
+
+    def get_file_size(self):
+        return self.total_file_size
+
+
+    def is_active(self):
+        if self.status == "Downloading":
+            return True
+        return False
+
+
+    def stop(self):
+        self.should_stop = True
+
+
+
+
+