SCP-2368: expose partial transactions that need to be balanced, signed and submitted by a remote wallet

[koslambrou]

First part of the hosted PAB scenario for a remote wallet client.

We expose partial transactions that need to be balanced, signed and submitted by the remote wallet.

What was done:

• New WalletEffect, yieldUnbalancedTx, which makes available an unbalanced tx to be balanced, signed and then submitted to the blockchain.

• Added ToJSON and FromJSON instances to ExportTx (partial tx)

• Additionnal Generic and OpenAPI.ToSchema orphan instances for some cardano-api types.

• New wallet handler in the PAB: RemoteClient. The only implemented wallet effect for the moment is YieldUnbalancedTx. The rest of the effects will be implemented in the future.

• Changed the PAB wallet config settings which allows the user to specify if the wallet is available locally or remotely.

• In the PAB, partial txs (ExportTx) are now exposed in the contract instance status endpoint (additionnaly as a NewYieldedPartialTx message in the websocket) when calling yieldUnbalancedTx.

Here's a simple setup to test this functionality:

1- In the plutus-pab.yaml config file, set the following attributes:

...
walletServerConfig:
  tag: RemoteWalletConfig
...
nodeServerConfig:
  ...
  mscNodeMode: AlonzoNode
...

2- Open a terminal and run cabal run plutus-pab:exe:plutus-pab-examples -- webserver --config plutus-pab/plutus-pab.yaml.sample

3- Open another terminal and execute the following shell script:

#!/usr/bin/env sh

INSTANCE_ID=$(curl -s -H "Content-Type: application/json" \
  --request POST \
  --data '{"caID": {"tag": "PayToWallet"}, "caWallet":{"getWalletId": "ffffffffffffffffffffffffffffffffffffffff"}}' \
  http://localhost:9080/api/contract/activate | jq -r '.unContractInstanceId')

curl -s http://localhost:9080/api/contract/instance/"$INSTANCE_ID"/status | jq

curl -H "Content-Type: application/json" \
  --request POST \
  --data '{"amount": {"getValue": [[{"unCurrencySymbol": ""}, [[{"unTokenName": ""}, 10000000]]]]}, "pkh": {"getPubKeyHash": "a2c20c77887ace1cd986193e4e75babd8993cfd56995cd5cfce609c2"}}' \
  'http://localhost:9080/api/contract/instance/'"$INSTANCE_ID"'/endpoint/PayToWallet'

sleep 1

curl -s http://localhost:9080/api/contract/instance/"$INSTANCE_ID"/status | jq

You should see a yielded tx similar the to following:

  "cicYieldedExportTxs": [
    {
      "transaction": "84a500800d80018182581d60a2c20c77887ace1cd986193e4e75babd8993cfd56995cd5cfce609c21a0098968002000e80a0f5f6",
      "redeemers": [],
      "inputs": []
    }
  ],

Pre-submit checklist:

• Branch
  • Tests are provided (if possible)
  • Commit sequence broadly makes sense
  • Key commits have useful messages
  • Relevant tickets are mentioned in commit messages
  • Formatting, materialized Nix files, PNG optimization, etc. are updated
• PR
  • Self-reviewed the diff
  • Useful pull request description
  • Reviewer requested

[silky]

Nice! :)

[weskinner]

I was able to reproduce locally, deserialize the transaction in the browser with cardano-serialization-lib, and sign the transaction with Nami wallet.

This branch of CSL was required to get it working: https://github.com/SundaeSwap-finance/cardano-serialization-lib/tree/fix-plutus-list-serialization

[koslambrou]

Before merging, I need to find out why the tx encoding is always 84a5...f5f6 even thought is pass in different UnbalancedTx each time.

[koslambrou]

My fault, the hex ARE different. Merging!