Summary

This package allows you generate a valid OverrideTypesBundle JSON file to inject into a polkadot-js ApiPromise under the typesBundle option key. This is a helper library that works specifically with polkadot-js. It is important to note that this library extracts chain types that are available via apps-config, if the chain types dont exist there it wont be able to support to bundle you need. Example packages that use this implicitly leverage this library are Substrate-api-sidecar, and Txwrapper-core.

Installation

NPM npm install -g @substrate/generate-type-bundle

Yarn yarn global add @substrate/generate-type-bundle

CLI

Options:
      --help             Show help                                     [boolean]
      --version          Show version number                           [boolean]
  -p, --path             Path to directory to generate Type files into. [string]
  -s, --specName         A chain to generate types for. If this is not inputted
                         it will create a types bundle for all chains.  [string]
  -a, --availableChains  List all available chains to generate types for.

Note: -p or --path is required.

Example CLI usage

Generating a Types Bundle to a specific path

-p or --path:

generate-type-bundle -p ~/Desktop/example/types

Note: This flag is required. The CLI will not generate any types bundles without specifying a directory.

Generate a Types Bundle for a specific chain

-s or --specName:

generate-type-bundle -p ~/Desktop/example/types -s moonbeam

List Available Chains

-a or --availableChains:

generate-type-bundle -a

Example Usage

Polkadot-js

import { ApiPromise } from '@polkadot/api';

const main = async () => {
    const api = await ApiPromise.create({
        provider: new WsProvider('ws://127.0.0.1:9944'),
        typesBundle: require('path-to-file.json')
    });
};

Substrate-api-sidecar

It is recommended to declare these env variables within a local .env file, but the below is an example usage from the terminal directly.

$ export SAS_SUBSTRATE_TYPES_BUNDLE=<path_to_file>
$ substrate-api-sidecar