fix: failure chain

README.rst

@@ -185,6 +185,8 @@ Other options:
                             timeout for downloading doujinshi
       -d DELAY, --delay=DELAY
                             slow down between downloading every doujinshi
+      --retry=RETRY         retry times when downloading failed
+      --exit-on-fail        exit on fail to prevent generating incomplete files
       --proxy=PROXY         store a proxy, for example: -p "http://127.0.0.1:1080"
       -f FILE, --file=FILE  read gallery IDs from file.
       --format=NAME_FORMAT  format the saved folder name

nhentai/cmdline.py

@@ -97,6 +97,10 @@ def cmd_parser():
                       help='timeout for downloading doujinshi')
     parser.add_option('--delay', '-d', type='int', dest='delay', action='store', default=0,
                       help='slow down between downloading every doujinshi')
+    parser.add_option('--retry', type='int', dest='retry', action='store', default=3,
+                      help='retry times when downloading failed')
+    parser.add_option('--exit-on-fail', dest='exit_on_fail', action='store_true', default=False,
+                      help='exit on fail to prevent generating incomplete files')
     parser.add_option('--proxy', type='string', dest='proxy', action='store',
                       help='store a proxy, for example: -p "http://127.0.0.1:1080"')
     parser.add_option('--file', '-f', type='string', dest='file', action='store',

nhentai/command.py

@@ -78,7 +78,8 @@ def main():
 
     if not options.is_show:
         downloader = Downloader(path=options.output_dir, threads=options.threads,
-                                timeout=options.timeout, delay=options.delay)
+                                timeout=options.timeout, delay=options.delay,
+                                retry=options.retry, exit_on_fail=options.exit_on_fail)
 
         for doujinshi_id in doujinshi_ids:
             doujinshi_info = doujinshi_parser(doujinshi_id)

nhentai/downloader.py

@@ -34,11 +34,13 @@ def download_callback(result):
 
 
 class Downloader(Singleton):
-    def __init__(self, path='', threads=5, timeout=30, delay=0):
+    def __init__(self, path='', threads=5, timeout=30, delay=0, retry=3, exit_on_fail=False):
         self.threads = threads
         self.path = str(path)
         self.timeout = timeout
         self.delay = delay
+        self.retry = retry
+        self.exit_on_fail = exit_on_fail
         self.folder = None
         self.semaphore = None
 
@@ -47,12 +49,14 @@ class Downloader(Singleton):
         for completed_task in asyncio.as_completed(tasks):
             try:
                 result = await completed_task
-                if result[1]:
+                if result[0] > 0:
                     logger.info(f'{result[1]} download completed')
                 else:
-                    logger.warning(f'{result[1]} download failed, return value {result[0]}')
+                    raise Exception(f'{result[1]} download failed, return value {result[0]}')
             except Exception as e:
                 logger.error(f'An error occurred: {e}')
+                if self.exit_on_fail:
+                    raise Exception('User intends to exit on fail')
 
     async def _semaphore_download(self, *args, **kwargs):
         async with self.semaphore:
@@ -88,10 +92,10 @@ class Downloader(Singleton):
 
             if not await self.save(filename, response):
                 logger.error(f'Can not download image {url}')
-                return 1, url
+                return -1, url
 
         except (httpx.HTTPStatusError, httpx.TimeoutException, httpx.ConnectError) as e:
-            if retried < 3:
+            if retried < self.retry:
                 logger.warning(f'Download {filename} failed, retrying({retried + 1}) times...')
                 return await self.download(
                     url=url,
@@ -101,12 +105,12 @@ class Downloader(Singleton):
                     proxy=proxy,
                 )
             else:
-                logger.warning(f'Download {filename} failed with 3 times retried, skipped')
+                logger.warning(f'Download {filename} failed with {self.retry} times retried, skipped')
-                return 0, url
+                return -2, url
 
         except NHentaiImageNotExistException as e:
             os.remove(save_file_path)
-            return -1, url
+            return -3, url
 
         except Exception as e:
             import traceback
@@ -114,10 +118,10 @@ class Downloader(Singleton):
             logger.error(f"Exception type: {type(e)}")
             traceback.print_stack()
             logger.critical(str(e))
-            return 0, url
+            return -9, url
 
         except KeyboardInterrupt:
-            return -3, url
+            return -4, url
 
         return 1, url