How do we get "LastVerified" for a Replica

[hannahhoward]

Just want to flag that determining the last time a deal was verified from the chain is not super easy. We had probably start thinking about the right Lotus API calls needed to get there.

[masih]

A bigger question here is what "verified" means. It can be:

• Deal is published, not expired, not slashed and active on Lotus API the call for which is StateMarketStorageDeal, and
• Attempt to retrieve a random range of data from the SP.

I think that's about as best as we can do?

Once that's done, then LastVerified would become an internal timestamp.

Also the FIP below will impact this to some extent and verification should ideally not be strongly tied to "deals":

• Direct data onboarding: Onboarding data without built-in market deals (FIP-0076) FIPs#730

[celine3650]

I was just catching up notes from the product discussion last week 9/12.

Based on the discussion, SP wants to put a green mark on the data verifiability as it's the core value prop of filecoin. That means to be able to read date / time of most recent successful verified deals for each blob is critical.
1. For each SP and given blob, when was the last time it was verified

And for each blob, what was the last successful time + most recent time is how we define "verified"
@masih @hannahhoward @elijaharita Do you agree if we use this as an acceptance criteria to determine the "Lastverified"?

Given the implementation difficulty, a proposed path is to separate diagnostics API that grants Filecoin information for information purposes. Any thoughts on that?

[masih]

@celine3650

• separate diagnostics API sounds reasonable and is already captured as an issue here: Offer diagnostics APIs to expose further detail about deal proposal lifecycle #43
• In the meantime, LastVerified data represents whatever Singularity defines as "Verified", which is the timestamp of a periodic check performed by Singularity that confirms:
  • deal is published
  • deal is active on chain.

[masih]

For Beta, scope reduced to #132. More sophisticated checking will be performed in Singularity eventually and Motion will remain a client of singularity in terms of reporting the last verified date. Therefore, removing the beta label from this issue.