Warn users when post-conditions indicate more spending then possible based on available balance

[314159265359879]

When a user is presented with a transaction to sign that has a postcondition to spend more than the available balance (for example STX), we can warn the user that the transaction will likely fail, check if they still want to sign the transaction.

I believe in this case it happened because the dapp checked the STX balance, but not the unlocked balance. It tried to spend about 1200 STX while there was only 92 available/unlocked (total was ~30,000, most of which was stacking).
https://explorer.hiro.so/txid/0xc3e58d2b0f6f8d2437b36ccde7024e2d77f86e66e4851ca329114d6d4becf593?chain=mainnet

The transaction failed

I believe we could have used the post-conditions to warn the user

The user send the same transaction 4 times, likely not understanding what was causing the issue. A warning in Leather could have helped.

[linear]

LEA-2302 Warn users when post-conditions indicate more spending then possible based on available balance

[camerow]

@314159265359879 looks like we've been reporting similar issues / for ~3y. This does seem like a nice enhancement but how many people would it truly help at the moment?

[camerow]

reference for older issues: LEA-67

[markmhendrickson]

This issue seems to have the most background info (via the comments): #3568

@314159265359879 should we close this issue and #1587 in favor of it as duplicates?

I agree this remains a useful enhancement and one that would likely help a significant amount of users. However, we may want to take a metrics-driven approach in terms of improving our tracking of transactions as they get broadcasted to the network and change state (to either success or failure), so we know the magnitude of failure rates for our users and can confirm just how common this particular failure case might be before proceeding with the enhancement.

I presume that this might entail setting up a broadcasting service (or leveraging our existing notifications service API?) that proxies the propagation of transactions to our service providers and checks in on them later. cc @alexp3y

Tracking the metrics issue here.

[github-actions]

This issue is stale because it has been open for 60 days with no activity.