Funds in unclaimed conditionalTransfer remain locked

[erkarl]

Current Behavior

After the locktime has expired the funds remain locked in the app.

Expected Behavior

The client should detect when the conditional transfer has not been claimed within the specified locktime and automatically call uninstallApp.(appInstanceId) to release the funds or dispute on-chain.

[kilrau]

or dispute on-chain

if the node decides not to cooperate, meaning uninstallApp.(appInstanceId) hits a timeout

[ArjunBhuptani]

Part of this will be solved here: #1101

And then we'll have to think through how the client/node clean up transfers on a schedule

[kilrau]

Agreed, connext/rest-api-client#37 was largely the same. Just transferring this small requirement here for clarity: client constantly retries claiming the htlc up to the dispute timeout. Then, as @erkarl described above, automatically calls uninstallApp.(appInstanceId) to release the funds or dispute on-chain if this doesn't work within a certain time period (we discussed one day). It should go on-chain well before htlc timeout.

[kilrau]

The client should detect when the conditional transfer has not been claimed within the specified locktime and automatically call uninstallApp.(appInstanceId) to release the funds or dispute on-chain.

As per recent discussion, we agreed that the client does not need to schedule htlc cleanups as long as
a) it exposes a simple call that an external service (like xud) could hit to cancel and clean-up unclaimed htlcs (please let us know which one since you mentioned two on the call @ArjunBhuptani @LayneHaber )
b) the node schedules automated uninstalling htlcs after expiry, retries if it fails
c) the client automatically triggers uninstalling expired htlcs on startup since b) can fail because client was offline