fix: unappliedSlashesAtActiveEra in staking/progress

[Imod7]

Description

While querying pallets/staking/progress in Kusama Asset Hub (example: public instance of KAH Sidecar), the below error is returned:

{
  "code": 500,
  "message": "unappliedSlashesAtActiveEra[0][1].map is not a function",
  "stack": "TypeError: unappliedSlashesAtActiveEra[0][1].map is not a function\n    at PalletsStakingProgressService.derivePalletStakingProgress (/usr/src/app/build/src/services/pallets/PalletsStakingProgressService.js:96:53)\n    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)\n    at async PalletsStakingProgressController.getPalletStakingProgress (/usr/src/app/build/src/controllers/pallets/PalletsStakingProgressController.js:119:32)\n    at async /usr/src/app/build/src/controllers/AbstractController.js:313:9",
  "level": "error"
}

Root Cause

When we call .entries() on UnappliedSlashes/StorageDoubleMap, it returns an array of [StorageKey, PendingSlashes] items where PendingSlashes is an object. However, we assume that PendingSlashes is an array and try to use map on it.

Suggested Solution

We should use map over unappliedSlashesAtActiveEra (== array) directly instead of unappliedSlashesAtActiveEra[0][1] (==PendingSlashes == object/struct).

The above is confirmed looking at the code in polkadot-sdk:

• UnappliedSlashes code --> shows that the UnappliedSlashes is a StorageDoubleMap.
• PendingSlashes code --> shows that the PendingSlashes is a struct thus an object (not an array).

The format of the unappliedSlashes.entries() (unappliedSlashesAtActiveEra) is also confirmed when I run in debug:

• unappliedSlashesAtActiveEra[0][0] --> StorageKey(92) [...]
• unappliedSlashesAtActiveEra[0][1] --> data of PendingSlashes object

{"validator":"D5aAp1y8XfkrmtPqsGFZtCjJrPZqKrsG2ceSha846jy6RMU","own":3289142260,"others":[["G1rrUNQSk7CjjEmLSGcpNu72tVtyzbWdUvgmSer9eBitXWf",5213796174],["G4RasQNUjgkXkdCuW2zgMJPcjZijaTmkJixb3oMxg9eiHng",58511039826],["F7oUkCrka4KGEmHpMweomYTh9ebrJ5e1SNoXCKqUVRXbxZ1",5746245842],["ESNmSiVRtezE2LmvXKAcZb4cm5hsSAVZkhMPLsRNiqPMjBp",847234987],["EFSNCLVUoTHTp2DcmQVw17YaouTxLAEQoVNoT9T1ToEb3SZ",279452729],["DDqMKWm7qerD9w4kXG1iYrMp4ac1sZ5Mak64A8B6XbDc3kn",127007745],["DXpDoDfFBh6iZX9JJZKgXs5d8NXM4f7eLch9RTQwiePZDX9",56688815]],"reporter":"Ed1xXhwva7tsK6sY5WnRQNVQ5bXC2kNbkpbU1EhjPZy4Cb6","payout":7407060837}

Testing

This solution works when testing

• with a local instance of Sidecar with .env file:

SAS_SUBSTRATE_URL=wss://kusama-asset-hub-rpc.polkadot.io
SAS_SUBSTRATE_MULTI_CHAIN_URL='[{"url":"wss://kusama-rpc.polkadot.io","type":"relay"}]'

• querying endpoint http://127.0.0.1:8080/pallets/staking/progress
• returns

 "unappliedSlashes": [
    {
      "validator": "D5aAp1y8XfkrmtPqsGFZtCjJrPZqKrsG2ceSha846jy6RMU",
      "own": "3289142260",
      "others": [
        [
          "G1rrUNQSk7CjjEmLSGcpNu72tVtyzbWdUvgmSer9eBitXWf",
          "5213796174"
        ],
        .....

Todos

• The mock tests need to be updated