Single message view 'thread next' points at older message for last message in thread

[hassanakbar4]

component_MailArchive: User Interface type_enhancement | by henrik@levkowetz.com

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I just now verified that the recent changes to postconfirmd, in setting the archived-At header field, was functioning, and picked an archived-at value for a just processed message from the log, and went to look at it in a browser.

There, I was happily surprised to see that date-next and -previous and thread-next and -previous arrows were available at the top of the page :-).

As expected for a message which had just arrived in the archive, the date-next arrow was greyed out, but counterintuitively, the thread-next message was not; it pointed at a message dated 2 days earlier.

In a mailing list, I expect date-next to go to the list message with the closest following timestamp, while the thread-next should go to the closest following timestamp limited by thread, not jump around in the time sequence ...

The message I was looking at was: https://mailarchive.ietf.org/arch/msg/detnet-dp-dt/uV0ZUTxPYrLcSc8kDX-GUTlEaJo and the thread-next arrow linked to: https://mailarchive.ietf.org/arch/msg/detnet-dp-dt/uJVp4hIt7Xi1Yo73A3v6AK1tae4

Best regards, Henrik

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Issue migrated from trac:2154 at 2021-09-22 16:48:07 +0500

[hassanakbar4]

@hassanakbar4 commented

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Unable to reproduce exact issue, thread links now point to different messages. During investigation of this issue discovered that there are cases where the thread_order value for a message differs between the search index and database. This should not happen, and will result in similar issues. Created scan function:

./scan_all.py check_thread_order 2017-01-01T00:00:00

which shows 154 messages out of sync. Investigating further.

[hassanakbar4]

@hassanakbar4 commented

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Hi Henrik,

Based on RFC7842, and my discussions with Robert, the thread display is supposed to be hierarchical, like that in MHonArc. In this case, if the second message is in a separate sub-branch it may follow the first message in thread order, even though it has an earlier date. This is indeed the case, when viewed in the MHonArc archive here:

https://www.ietf.org/mail-archive/web/detnet-dp-dt/current/threads.html#00470

Select the message, then click 'Next in Thread' twice to get to the referenced message.

In light of this, can this issue be closed?

[hassanakbar4]

@hassanakbar4 commented

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Replying to [comment:2 rcross@…]:

Hi Henrik,

Based on RFC7842, and my discussions with Robert, the thread display is supposed to be hierarchical, like that in MHonArc.

That's fine as the default message list view, but in that view, you should have the option to sort by column header, which should flatten the hierarchical view but keep each thread distinct. Indeed, in Section 2.1, RFC7842 goes on to say about thread view that the enhancement will:

   o  Modify the sort performed by the clicking on the column headers to
      sort the overall list first by the parameters in the first message
      in the thread, and then sort within the thread (ensuring the
      thread grouping doesn't change based on these sorts).  When
      viewing threads sorted this way, the hierarchy will be flattened,
      but the thread boundaries will remain visibly distinct.

I believe that's not implemented yet, but when it's in place it will let me read threads in the chronological order that the thread's messages were sent to the list, in the message pane of the list view.

In this case, if the second message is in a separate sub-branch it may follow the first message in thread order, even though it has an earlier date. This is indeed the case, when viewed in the MHonArc archive here:

https://www.ietf.org/mail-archive/web/detnet-dp-dt/current/threads.html#00470

Yes, I see.

Select the message, then click 'Next in Thread' twice to get to the referenced message.

In light of this, can this issue be closed?

This explains the situation, but it still doesn't make me particularly happy. In all my threaded reading of IETF mailing lists, I've preferred to see messages in the order they have arrived, rather than the way that thread-previous and thread-next works now; I think this was originally triggered by some people responding to discussions in one sub-thread by replying to the latest message in the thread, even if that message might belong to a different sub-thread. So the abstract thread of discussion would not necessarily follow the hierarchical thread tree, while a chronological thread sequence would always be true in that responses would come later than the messages they responded to.

So what I'm saying here is that the default hierarchical list-view is fine as such, as long as there's an option to sort within the thread chronologically, as specified in the RFC; but in the single-message view I believe a chronological thread-next linkage would serve us better than what MHonArc implements.

Best regards,

Henrik

[hassanakbar4]

@hassanakbar4 changed type from defect to enhancement

[hassanakbar4]

@hassanakbar4 _changed status from new to under_review_