@polkadot/types/interfaces/chain/rpc.js

export const rpc = {
    getBlock: {
        description: 'Get header and body of a relay chain block',
        params: [
            {
                isHistoric: true,
                isOptional: true,
                name: 'hash',
                type: 'BlockHash'
            }
        ],
        type: 'SignedBlock'
    },
    getBlockHash: {
        description: 'Get the block hash for a specific block',
        params: [
            {
                isOptional: true,
                name: 'blockNumber',
                type: 'BlockNumber'
            }
        ],
        type: 'BlockHash'
    },
    getFinalizedHead: {
        alias: ['chain_getFinalisedHead'],
        description: 'Get hash of the last finalized block in the canon chain',
        params: [],
        type: 'BlockHash'
    },
    getHeader: {
        alias: ['chain_getHead'],
        description: 'Retrieves the header for a specific block',
        params: [
            {
                isHistoric: true,
                isOptional: true,
                name: 'hash',
                type: 'BlockHash'
            }
        ],
        type: 'Header'
    },
    subscribeAllHeads: {
        description: 'Retrieves the newest header via subscription',
        params: [],
        pubsub: [
            'allHead',
            'subscribeAllHeads',
            'unsubscribeAllHeads'
        ],
        type: 'Header'
    },
    subscribeFinalizedHeads: {
        alias: ['chain_subscribeFinalisedHeads', 'chain_unsubscribeFinalisedHeads'],
        description: 'Retrieves the best finalized header via subscription',
        params: [],
        pubsub: [
            'finalizedHead',
            'subscribeFinalizedHeads',
            'unsubscribeFinalizedHeads'
        ],
        type: 'Header'
    },
    subscribeNewHeads: {
        alias: ['chain_unsubscribeNewHeads', 'subscribe_newHead', 'unsubscribe_newHead'],
        description: 'Retrieves the best header via subscription',
        params: [],
        // NOTE These still has the aliassed version, compatible with 1.x
        pubsub: [
            'newHead',
            'subscribeNewHead',
            'unsubscribeNewHead'
        ],
        type: 'Header'
    }
};