Add ability to search for online accounts

[urtho]

Upstream issue : algorand#1629

Problem

There is no way to quickly fetch all online accounts[^1].

Solution

• Add is-online boolean filter to account search endpoint
• Add is-reward-eligible boolean filter to account search endpoint
• Add expires-in-hours filter that returns only accounts that will expire no later than expires-in-hours
• Add appropriate optional partial index (for is-online only)

Response model should include:

• total online stake
• total eligible online stake
• avg block time for the last 100 rounds in milliseconds

Notes:

• is-reward-eligible assumes is-online
• expires-in-hours should calculate avg block time over last 100 blocks using a query to block_header
• return only accounts with non-expired keys (as online flag persists past key expiry)
• expires-in-hours might need a better name like expires-in-hours-or-less but shorter ;)

[urtho]

Let's wait a bit for a confirmation on how suspended accounts look like (is-online:false + valid keyreg ?) so that we can show paused accounts in the results as well.

[urtho]

Thinking we should publish new , not yet merged functionality under different prefix instead of /v2. This would allow us not to break apps that used bleeding-edge stuff after the feature got renamed during the final merge.

[agodnic]

Let's wait a bit for a confirmation on how suspended accounts look like (is-online:false + valid keyreg ?) so that we can show paused accounts in the results as well.

Do we have a confirmation of this?

Sorry if this is a dumb question, I don't know what suspended/paused accounts are. A quick google search yielded this:

[...] the network to suspend delinquent participants/ accounts from the staking set. Where that participant/account has
failed to execute their incumbent responsibilities

[urtho]

still no confirmation.
Lets assume for now that suspended account will have online = false and a valid (last key round greater than current round) key material still on the account.

We will also need a block search endpoint with filters like proposer , booted proposer - but will create a separate issue for that.

[gmalouf]

@urtho think you may have what you need now (have to check on the suspended status as of round X)

[agodnic]

@gmalouf, the the remaining features in this specification are:

1. is-reward-eligible filter
2. expires-in-hours filter
3. Add stake metada to the response in GET /v2/accounts
4. Add avg block time to the response in GET /v2/accounts

Let us know if you're interested in any