WASM Smart Contract With Patract Labs

Patract Labs

• Patract’s mission is to accelerate the smart contract industry’s transition to Wasm technology stack.

• Official Website: https://patract.io/

• Documents Warehouse: https://docs.patract.io/en#

Slides and transcripts

• For the speaker's slides, please refer WASM Smart Contract with Patract Labs

• For the speaker's transcript, please refer Transcript

Documents

• Redspot: Contract Dev Scaffold
• Europa: Contract Sandbox Env
• Metis: Standard Contract Library

Demo Setup

Making sure you have cargo-contract setup: Please follow the guide on ink! to setup rust, cargo and cargo-contracts

Making sure you have npx installed

1. Start your first Redspot Project using Redspot templates:

npx redspot-new erc20

remember to change the dependencies in cargo.toml to pull from crate.io, otherwise it will have compatible issues with polkadot.js

ink_primitives = { version = "3.0.0-rc5", default-features = false }
ink_metadata = { version = "3.0.0-rc5", default-features = false, features = ["derive"], optional = true }
ink_env = { version = "3.0.0-rc5", default-features = false }
ink_storage = { version = "3.0.0-rc5", default-features = false }
ink_lang = { version = "3.0.0-rc5", default-features = false }

2. Download Europa-UI

Detailed release information can be found here Release v0.3.32. Currently, 3 operating systems are supportd:

• Windows 10 (21H1 and above)europa-ui-v0.3.32-x86_64-win.exe
• MacOS (10.15.7 and above)europa-ui-v0.3.32-x86_64-darwin.dmg
• Ubuntu (20.04 and above)europa-ui-v0.3.32-x86_64-linux.AppImage

For ubuntu, remember to give it permission chmod +x europa-ui-v0.3.32-x86_64-linux.AppImage

3. Start Europa-UI

• Simply double click the icon to start it. Making sure the default port is not occupied.

• Click start to start the node.

4. Test Redspot + Europa using templated contract and config

npx redspot run scripts/deploy.ts

It will compile the contracts and update contract + metadata to Europa-UI. If the metadata does not get uploaded correctly, you can manual add that.

• open Europa-UI, you should be able to see the contract has been successfully deployed.
• you can use back to Block to revert the blockchain and remove the deployed test contract

5. Copy dependency in Cargo.toml and contract code in lib.rs into erc20/contracts/Cargo.toml and erc20/contracts/lib.rs

6. Build your contract with

cd contracts
cargo +nightly contract build --keep-debug-symbols --optimization-passes=0

then copy it to artifacts dir under erc20 directory

this will build the contract in debug mode and keeps all debug symbols.

mkdir ../artifacts
cp ./target/ink/erc20_pausable.contract ../artifacts/
cp ./target/ink/metadata.json ../artifacts/erc20_pausable.json 

7. write the deployment script.

   • copy the code from deploy.ts
   • npx redspot run scripts/deploy.ts --no-compile
   • open Europa-UI to check if the contract has been successfully deployed

8. Writing tests:

   • copy all the code from tests
   • npx redspot test ./tests/erc20_pausable_init.test.ts --no-compile
   • npx redspot test ./tests/erc20_pausable_ownable.test.ts --no-compile
   • npx redspot test ./tests/erc20_pausable_pause.test.ts --no-compile