watcher-ts/packages/graph-node/ipld-demo.md

Demo for IPLD statediff and checkpointing

• In the root of watcher-ts, run:

  yarn && yarn build
  

• In console, run the IPFS daemon:

  # Verify ipfs version
  ipfs version
  # ipfs version 0.12.2
  
  ipfs daemon
  

• The following services should be running to work with watcher:

  • vulcanize/go-ethereum (v1.10.17-statediff-3.2.0) on port 8545.
  • vulcanize/ipld-eth-server (v3.0.0) with native GQL API enabled on port 8082 and RPC API enabled on port 8081.

• Deploy Example contract:

  cd packages/graph-node
  
  yarn example:deploy
  

• Set the returned address to the variable $EXAMPLE_ADDRESS:

  EXAMPLE_ADDRESS=
  

• In packages/graph-node, run:

  cp .env.example .env
  

  • In .env file, set EXAMPLE_CONTRACT_ADDRESS to the EXAMPLE_ADDRESS.

  • In packages/graph-node/test/subgraph/example1/subgraph.yaml, set the source address for Example1 datasource to the EXAMPLE_ADDRESS.

  yarn build:example
  

• In packages/codegen, create a config.yaml file with the following contents:

  contracts:
    - name: Example
      path: ../graph-node/test/contracts/Example.sol
      kind: Example1
  
  outputFolder: ../demo-example-watcher
  mode: all
  kind: active
  port: 3008
  flatten: true
  subgraphPath: ../graph-node/test/subgraph/example1/build
  

  Reference: packages/codegen/README.md

• Generate watcher:

  cd packages/codegen
  
  yarn codegen --config-file ./config.yaml
  

• In packages/demo-example-watcher, run:

  yarn
  

• Create dbs:

  sudo su - postgres
  # Delete databases if they already exist.
  dropdb demo-example-watcher
  dropdb demo-example-watcher-job-queue
  
  # Create databases
  createdb demo-example-watcher
  createdb demo-example-watcher-job-queue
  

  Enable the pgcrypto extension.

  psql -U postgres -h localhost demo-example-watcher-job-queue
  
  demo-example-watcher-job-queue=# CREATE EXTENSION pgcrypto;
  demo-example-watcher-job-queue=# exit
  

• In a new terminal, in packages/demo-example-watcher, run:

  yarn server
  

  yarn job-runner
  

• Run the following GQL subscription at the graphql endpoint:

  subscription {
    onEvent {
      event {
        __typename
        ... on TestEvent {
          param1
          param2
          param3
        },
      },
      block {
        number
        hash
      }
    }
  }
  

• Trigger the Test event by calling example contract method:

  cd packages/graph-node
  
  yarn example:test --address $EXAMPLE_ADDRESS
  

  A Test event shall be visible in the subscription at endpoint.

• Run the getState query at the endpoint to get the latest IPLDBlock for EXAMPLE_ADDRESS:

  query {
    getState (
      blockHash: "EVENT_BLOCK_HASH"
      contractAddress: "EXAMPLE_ADDRESS"
      kind: "diff_staged"
    ) {
      cid
      block {
        cid
        hash
        number
        timestamp
        parentHash
      }
      contractAddress
      data
    }
  }
  

• Run the query for entity at the endpoint:

  query {
    author (
      block: {
        hash: "EVENT_BLOCK_HASH"
      }
      id: "0xdc7d7a8920c8eecc098da5b7522a5f31509b5bfc"
    ) {
      __typename
      name
      paramInt
      paramBigInt
      paramBytes
    }
  }
  

• diff IPLDBlocks get created corresponding to the diff_staged blocks when their respective eth_blocks reach the pruned region.

• In packages/demo-example-watcher:

  • After the diff block has been created, create a checkpoint:

    cd packages/demo-example-watcher
    
    yarn checkpoint --address $EXAMPLE_ADDRESS
    

    • A checkpoint IPLDBlock should be created at the latest canonical block hash.

    • Run the getState query again at the endpoint with the output blockHash and kind checkpoint.

• All the IPLDBlock entries can be seen in pg-admin in table ipld_block.

• All the diff and checkpoint IPLDBlocks should be pushed to IPFS.

• Open IPFS WebUI http://127.0.0.1:5001/webui and search for IPLDBlocks using their CIDs.