Retrieve_series_metadata Hangs Indefinitely Without Timeout

[by3nrique]

The retrieve_series_metadata function is exhibiting unexpected behavior where it gets stuck and does not raise a timeout exception even after waiting for an extended period (hours) . This issue occurs when attempting to retrieve metadata for a specific series using the retrieve_series_metadata function with a certain series_uid and study_uid.

To improve the context:

• The same series_uid and study_uid hang indefinetly alse with retrieve_series and retrieve_study method.

• The same series_uid and study_uid return good result for the search_for_series method (<1s).

• For different series_uid all the methods seem to work so a WADO-RS avaliabity issue on the server can be discarded (At least 1000 series tested).

Although we definitely cannot rule out a bug in our end (any suggestions in this regard are welcome) the library should have a method to hang a request that takes too long.

[sb335c]

@by3nrique I see the same thing sometimes. Did you come up with a solution?

[by3nrique]

The most practical solution I found is to implement a manual timeout context to prevent the process from hanging when the library fails to manage read timeouts. However, I have found out this issue often occurs because search_for_series (QIDO) only queries the database, while retrieve_series_metadata (WADO) must access the physical DICOM files. In my experience, if the PACS has studies in near-line storage or "offline" archives, the system can hang indefinitely because the retrieval or refresh process isn't always automatic. Since the server keeps the socket open while waiting for the storage to respond, the client never receives an error and stays stuck. I recommend wrapping the call in a signal-based timeout or a secondary thread to force a break after 30 or 60 seconds of inactivity. Finally, I suggest reviewing several failing studies individually to identify a pattern

[CPBridge]

Hi @by3nrique and @sb335c

I agree that there should be a timeout on all requests by default. This is simple to achieve using the timeout parameter of the underlying requests library. I created a PR for this in #124. Would either of you be able to test this and give any feedback?

[CPBridge]

Resolved by #124