Backfill of LibreLinkUp follower data?

[PhilaBurger]

When using LibreLinkUp or Nightscout as a data source and there's a break in connectivity to the source, it would be nice if xDrip4iOS could retrieve any data between it's last known data point and the current time.

This would benefit anyone who finds themselves in locations without solid cellular or wifi service (fortified buildings, air travel), in that missing data could be retrieved and displayed once their CGM data has been uploaded to the backend from which xDrip4iOS is configured to retrieve.

[paulplant]

@PhilaBurger , would you be able/willing to share a LibreLinkUp follower account that we can use to develop this idea? I don't have access to one currently.

Please share via e-mail to xdrip@proximus.be (or to me directly via Facebook Messenger). Or maybe if I give you an e-mail address you can invite me to follow you and then I can use this new account for all testing work.

[PhilaBurger]

On 2025-10-01 11:21, Paul Plant wrote: paulplant left a comment (JohanDegraeve/xdripswift#663) [1] @PhilaBurger [2] , would you be able/willing to share a LibreLinkUp follower account that we can use to develop this idea? I don't have access to one currently. Please share via e-mail to ***@***.*** (or to me directly via Facebook Messenger). Or maybe if I give you an e-mail address you can invite me to follow you and then I can use this new account for all testing work. -- Reply to this email directly, view it on GitHub [1], or unsubscribe [3]. You are receiving this because you were mentioned.Message ID: ***@***.***>

I've gone ahead and sent an email with the credentials I've created for you. The connection is configured and confirmed to be displaying data.

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-- [4] "It's always suicide-mission this, save-the-planet that. No one ever just stops by to say 'hi' anymore." --Colonel Jack O'Neill, SG1 Links: ------ [1] #663 (comment) [2] https://github.com/PhilaBurger [3] https://github.com/notifications/unsubscribe-auth/A5QFCMAEFCNGEVLU4Y5AOFD3VPWOFAVCNFSM6AAAAACHJYR2A2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTGNJWHEZTSNBYHA [4] https://poplme.co/hash/lqQkxj0F/1/es

[RazorWuzHere]

I’d love to see this BUT for data consistency reasons, any chance the backfill d values could be on odd color or a tiny square/triangle instead of the dot?

I’d be happy to help in testing any way I can.

[paulplant]

@PhilaBurger I'm looking into this and I'm not quite sure there is really an issue.

If the app is closed (or not able to reach the server for whatever reason), then open re-opening it does backfill with the whole history (back until just after the previously stored BG reading).

It's true that there is a gap between the latest BG value and when the historical values start of 20-30 minutes and this will always be shown as a gap (because there is no data for this timeframe), but the rest of the backfill (5-minute values) is fully processed and backfilled into the app.

I'm running my test app in "keep-alive = disabled" mode which basically sleeps the app (no background activity/downloads) until I reopen the app again.

In the below image you can see that I opened it 3 times and each time it fully backfilled all "available" data. Except the 20 minute gap that exists in the data the LLU server sends us between the current value and the start of the historial values.

Don't you see this happening in your app? Or are we maybe talking about different things?

[paulplant]

I’d love to see this BUT for data consistency reasons, any chance the backfill d values could be on odd color or a tiny square/triangle instead of the dot?

How does this relate to data consistency? What problem are you trying to fix by having the values in a different colour?

I think it could be useful in the BgReadings (and detail view) to have some indicator that the value is from a backfill stream, but on the main chart how would making it stand out help you? I'm just trying to understand.

[RazorWuzHere]

I’d love to see this BUT for data consistency reasons, any chance the backfill d values could be on odd color or a tiny square/triangle instead of the dot?

How does this relate to data consistency? What problem are you trying to fix by having the values in a different colour?

I think it could be useful in the BgReadings (and detail view) to have some indicator that the value is from a backfill stream, but on the main chart how would making it stand out help you? I'm just trying to understand.

Sorry Paul. Data consistency was not the right term here. I was just thinking that it would be an indicator for data/connection issues. For example, if it did backfill already, I might not have ever noticed the current issue I "me too'd" ON FB post from Oliver Wykes about missing readings randomly throughout the day. The detail view would be a good place to indicate this instead of the main chart.

[paulplant]

Perfect... that explanation makes sense. I think we understand the same then. I'll look into it. Maybe a small visual marker on the BgReadingsView and also in the BgReadingsViewDetail screen would be good.

This will need changes to coredata schema so I want to be careful. I'll look into it.

There were several "Me Tooers" :) Are you Oliver?

[RazorWuzHere]

Perfect... that explanation makes sense. I think we understand the same then. I'll look into it. Maybe a small visual marker on the BgReadingsView and also in the BgReadingsViewDetail screen would be good.

This will need changes to coredata schema so I want to be careful. I'll look into it.

There were several "Me Tooers" :) Are you Oliver?

No sir. I'm Ray. Posted a screen shot of xdrip chart vs dexcom g7 chart for reference. Any info I can provide that might help, please feel free to ask.