Polkadart Milestone 2

[Lohann]

Milestone Delivery Checklist

• The milestone-delivery-template.md has been copied and updated.
• The invoice form 📝 has been filled out for this milestone.
• This pull request is being made by the same account as the accepted application.
• In case of acceptance, the payment will be transferred to the BTC/ETH payment address provided in the application.
• The delivery is according to the Guidelines for Milestone Deliverables.

Link to the application pull request: w3f/Grants-Program#1053

[keeganquigley]

@Lohann thanks for the delivery. Someone will take a look at it soon.

[keeganquigley]

@Lohann I'm in the process of evaluating your delivery. A couple of initial comments:

• There are quite a few broken links in your delivery. Can you update these please?
• I'm not super familiar with Dart, should I just be running dart test in the root folder to run all tests for the project? Or do I need to run it in each of the test folders separately? Thanks!

[Lohann]

Hey @keeganquigley for sure I'll check the links, for running the tests you can do the following:

# install git-lfs
brew install git-lfs
git lfs fetch
git lfs checkout

# Install dependencies for all packages
./scripts/run_dart_pub_get.sh

# Run tests
./scripts/run_tests.sh

If you are interested in a more hands-on approach, we published a pre-release version of all packages on pub.dev:

You can get started doing the following:
1 - Create a new project

dart create -t console polkadart-milestone-2
cd polkadart-milestone-2

2 - Add those dependencies to pubspec.yaml

...
dependencies:
  polkadart: ^0.1.0-pre.2
  ss58: ^1.1.0-pre.1

dev_dependencies:
  lints: ^2.0.0
  test: ^1.16.0
  polkadart_cli: ^0.1.0-pre.1

polkadart:
  output_dir: bin/generated
  chains:
    polkadot: wss://rpc.polkadot.io

3 - Run following command for generate the Dart types from polkadot metadata:

dart run polkadart_cli:generate -v

4 - Replace the contents of bin/polkadart_milestone_2.dart with following sample code:

import 'package:ss58/ss58.dart' show Address;
import './generated/polkadot/polkadot.dart' show Polkadot;

void main(List<String> arguments) async {
  final Polkadot polkadot = Polkadot.url(Uri.parse('wss://rpc.polkadot.io'));

  // Account from SS58 address
  final account = Address.decode('19t9Q2ay58hMDaeg6eeBhqmHsRnc2jDMV3cYYw9zbc59HLj');

  // Retrieve Account Balance
  final accountInfo = await polkadot.query.system.account(account.pubkey);
  print('Balance: ${accountInfo.data.free}');

  // Retrieve Runtime Version
  final runtimeVersion = await polkadot.rpc.state.getRuntimeVersion();
  print('Runtime Version: ${runtimeVersion.specVersion}');

  await polkadot.disconnect();
}

5 - For run the code above, just run:

dart run

[Lohann]

@keeganquigley thanks for the heads up, broken links fixed ✅

[keeganquigley]

Thanks for the changes @Lohann! The test scripts work great. I appreciate the hands-on tutorial as well.

Running docker compose up however, gives me this error:

Attaching to polkadart-tests-1
polkadart-tests-1  | The current Dart SDK version is 2.19.5.
polkadart-tests-1  | 
polkadart-tests-1  | Because every version of flutter from sdk depends on sky_engine from sdk which requires SDK version >=3.0.0-0 <4.0.0, flutter from sdk is forbidden.
polkadart-tests-1  | So, because polkadart_example depends on flutter from sdk, version solving failed.
polkadart-tests-1  | 
polkadart-tests-1 exited with code 65

I think maybe there is a version error. Does a certain Flutter version need to be specified in the Dockerfile?

[leonardocustodio]

Hello @keeganquigley , that's my bad. I forgot to update the Dockerfile. Can you fresh clone the repository and try again?

[keeganquigley]

Thanks for the changes @leonardocustodio yep it works now! I'm happy to pass the milestone, and will forward your invoice internally for payment.

You can find my final eval here.

[semuelle]

@Lohann, the postal address on your invoice doesn't match the one in the grant application. If your postal address changed, could you submit an amendment to the contract with the new address, please?

[Lohann]

@semuelle thanks of the heads up, invoice updated ✅

[semuelle]

@Lohann, I was referring to this address. Also, the invoice shows January as the date. Could you update again?

[Lohann]

@semuelle hmm, maybe I attached the invoice from Milestone 1 by mistake, could you check again? I've sent from [email protected] the invoice title is Polkadart-Milestone-2-Invoice.pdf

[keeganquigley]

@semuelle @Lohann sorry, this was my fault. Looks like I attached the wrong invoice when I sent the email. The one you submitted on March 31st appears to be correct, as well as the most recent one. I will send this again. My apologies!