watcher-ts/packages/erc20-watcher/demo.md

Demo

• The following core services need to be running for the demo:

  • ipld-eth-db
    • Version: v4.2.3-alpha
  • geth
    • State diffing service should use ipld-eth-db for database.
    • Version: v1.10.26-statediff-4.2.2-alpha
    • Endpoint: http://127.0.0.1:8545
  • ipld-eth-server
    • Should use ipld-eth-db for database.
    • Version: v4.2.3-alpha
    • Endpoints:
      • GQL: http://127.0.0.1:8082/graphql
      • RPC: http://127.0.0.1:8081

• Create a postgres12 database for the watcher:

  sudo su - postgres
  
  # If database already exists
  # dropdb erc20-watcher
  
  createdb erc20-watcher
  

• Create database for the job queue and enable the pgcrypto extension on them (https://github.com/timgit/pg-boss/blob/master/docs/usage.md#intro):

  # If database already exists
  # dropdb erc20-watcher-job-queue
  
  createdb erc20-watcher-job-queue
  

  postgres@tesla:~$ psql -U postgres -h localhost erc20-watcher-job-queue
  Password for user postgres:
  psql (12.7 (Ubuntu 12.7-1.pgdg18.04+1))
  SSL connection (protocol: TLSv1.3, cipher: TLS_AES_256_GCM_SHA384, bits: 256, compression: off)
  Type "help" for help.
  
  erc20-watcher-job-queue=# CREATE EXTENSION pgcrypto;
  CREATE EXTENSION
  erc20-watcher-job-queue=# exit
  

• In the config file update the database connection settings.

• In watcher-ts repo, follow the instructions in Setup for installing and building packages.

  # After setup
  yarn && yarn build
  

• Run the job-runner:

  yarn job-runner
  

• Run the watcher:

  yarn server
  

• Deploy an ERC20 token:

  yarn token:deploy
  # GLD Token deployed to: TOKEN_ADDRESS
  

  Export the address of the deployed token to a shell variable for later use:

  export TOKEN_ADDRESS="<TOKEN_ADDRESS>"
  

• Run the following command to watch the contract:

  yarn watch:contract --address $TOKEN_ADDRESS --kind ERC20 --checkpoint false
  

• Add a second account to Metamask and export the account address to a shell variable for later use:

  export RECIPIENT_ADDRESS="<RECIPIENT_ADDRESS>"
  

• To get the current block hash at any time, run:

  yarn block:latest
  

• Run the following GQL query against the GraphQL endpoint to get name, symbol and total supply of the deployed token:

  query {
    name(
      blockHash: "LATEST_BLOCK_HASH"
      token: "TOKEN_ADDRESS"
    ) {
      value
      proof {
        data
      }
    }
  
    symbol(
      blockHash: "LATEST_BLOCK_HASH"
      token: "TOKEN_ADDRESS"
    ) {
      value
      proof {
        data
      }
    }
  
    totalSupply(
      blockHash: "LATEST_BLOCK_HASH"
      token: "TOKEN_ADDRESS"
    ) {
      value
      proof {
        data
      }
    }
  }
  

• Run the following GQL query against the GraphQL endpoint to get balances for the main and the recipient account at the latest block hash:

  query {
    fromBalanceOf: balanceOf(
        blockHash: "LATEST_BLOCK_HASH"
        token: "TOKEN_ADDRESS",
        # main account having all the balance initially
        owner: "0xDC7d7A8920C8Eecc098da5B7522a5F31509b5Bfc"
      ) {
      value
      proof {
        data
      }
    }
    toBalanceOf: balanceOf(
        blockHash: "LATEST_BLOCK_HASH"
        token: "TOKEN_ADDRESS",
        owner: "RECIPIENT_ADDRESS"
      ) {
      value
      proof {
        data
      }
    }
  }
  

• Run the following GQL subscription at the GraphQL endpoint:

  subscription {
    onEvent {
      blockHash
      contract
      event {
        __typename
        ... on TransferEvent {
          from
          to
          value
        },
        ... on ApprovalEvent {
          owner
          spender
          value
        }
      }
      proof {
        data
      }
    }
  }
  

• Transfer tokens to the recipient account:

  yarn token:transfer --token $TOKEN_ADDRESS --to $RECIPIENT_ADDRESS --amount 100
  

  • A Transfer event to RECIPIENT_ADDRESS shall be visible in the subscription at endpoint.

  • Fire the GQL query above to get updated balances for the main (from) and the recipient (to) account.