fix: return exit code from download subprocess

Use a multiprocessing queue to return the exit code from the download.run() function; if the queue is empty then fall back to the process exit code

gallery_dl_server/__init__.py

@@ -114,9 +114,10 @@ async def lifespan(app):
 def download_task(url, options):
     """Initiate download as a subprocess and log output."""
     log_queue = multiprocessing.Queue()
+    return_status = multiprocessing.Queue()
 
     process = multiprocessing.Process(
-        target=download.run, args=(url, options, log_queue)
+        target=download.run, args=(url, options, log_queue, return_status)
     )
     process.start()
 
@@ -139,7 +140,10 @@ def download_task(url, options):
 
     process.join()
 
-    exit_code = process.exitcode
+    try:
+        exit_code = return_status.get(block=False)
+    except queue.Empty:
+        exit_code = process.exitcode
 
     if exit_code == 0:
         log.info("Download job completed with exit code: 0")

gallery_dl_server/download.py

@@ -6,7 +6,7 @@
 log = output.initialise_logging(__name__)
 
 
-def run(url, options, log_queue):
+def run(url, options, log_queue, return_status):
     """Set gallery-dl configuration, set up logging and run download job."""
     config.clear()
 
@@ -43,7 +43,7 @@ def run(url, options, log_queue):
         status = -1
         log.error(f"Exception: {e}")
 
-    return status
+    return_status.put(status)
 
 
 def config_update(options):

gallery_dl_server/output.py

@@ -201,7 +201,7 @@ def write(self, msg):
             return
 
         if msg.startswith("# "):
-            msg = f"File already exists or its ID is in a download archive: {msg.removeprefix("# ")}"
+            msg = f"File already exists or its ID is in a download archive: {msg.removeprefix('# ')}"
             self.level = logging.WARNING
 
         self.logger.log(self.level, msg.strip())
@@ -213,7 +213,7 @@ def flush(self):
 class NullWriter:
     """Suppress writes to stdout or stderr."""
 
-    def write(self, message):
+    def write(self, msg):
         pass
 
     def flush(self):