watcher-ts/packages/codegen

Code Generator

Setup

• Run the following command to install required packages:

  yarn
  

Run

• Run the following command to generate a watcher from a contract file:

  yarn codegen --input-file <input-file-path> --contract-name <contract-name> --output-folder [output-folder] --mode [eth_call | storage | all] --flatten [true | false]
  

  • input-file(alias: i): Input contract file path or an URL (required).
  • contract-name(alias: c): Main contract name (required).
  • output-folder(alias: o): Output folder path. (logs output using stdout if not provided).
  • mode(alias: m): Code generation mode (default: all).
  • flatten(alias: f): Flatten the input contract file (default: true).

  Note: When passed an URL as input-file, it is assumed that it points to an already flattened contract file.

  Examples:

  Generate code in both eth_call and storage mode.

  yarn codegen --input-file ./test/examples/contracts/ERC20.sol --contract-name ERC20 --output-folder ../my-erc20-watcher --mode all
  

  Generate code in eth_call mode using a contract provided by URL.

  yarn codegen --input-file https://git.io/Jupci --contract-name ERC721 --output-folder ../my-erc721-watcher --mode eth_call
  

  Generate code in storage mode.

  yarn codegen --input-file ./test/examples/contracts/ERC721.sol --contract-name ERC721 --output-folder ../my-erc721-watcher --mode storage
  

Demo

• In root of the repository:

  • Install required packages:

    yarn
    

  • Build files:

    yarn build
    

• Generate a watcher from a contract file:

  yarn codegen --input-file ../../node_modules/@openzeppelin/contracts/token/ERC20/ERC20.sol --contract-name ERC20 --output-folder ../demo-erc20-watcher --mode eth_call
  

  This will create a folder called demo-erc20-watcher containing the generated code at the specified path. Follow the steps in demo-erc20-watcher/README.md to setup and run the generated watcher.

• Generate a watcher from a flattened contract file from an URL:

  yarn codegen --input-file https://git.io/Jupci --contract-name ERC721 --output-folder ../demo-erc721-watcher --mode eth_call
  

References

• ERC20 schema generation (eth_call mode).
• ERC20 schema generation (storage mode).
• ERC721 schema generation (eth_call mode).
• ERC721 schema generation (storage mode).

Known Issues

• Currently, node-fetch v2.6.2 is being used to fetch from URLs as v3.0.0 is an ESM-only module and ts-node transpiles to import it using require.