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Intermediate

 

How to build a subgraph and deploy it locally

This tutorial will guide you through the process of building and deploying a subgraph on a local node using the graph-cli and docker-compose. The tutorial begins by providing instructions for installing the graph-cli, then it goes on to explain how to build a local graph-indexer node by copying and pasting a provided docker-compose file and modifying it to match the network you want to connect to. The tutorial then goes on to explain how to run the indexer node using docker-compose and how to check the logs to ensure the node is syncing with the Harmony chain. The tutorial assumes that the reader has basic knowledge of using command line interface and have installed the docker and docker-compose in the system.

Install the graph-cli

​ ​

Build your own graph-indexer local node

Copy paste the below docker-compose file and replace services.graph-node.environment.ethereum accordingly to the network: mainnet s0 : mainnet:archive,traces:https://a.api.s0.t.hmny.io mainnet s1 : mainnet:archive,traces:https://a.api.s1.t.hmny.io

mainnet s0

mainnet s1

version: "3"
services:
  graph-node:
    container_name: hmy_indexer
    image: graphprotocol/graph-node:latest
    ports:
      - "8000:8000"
      - "8001:8001"
      - "8020:8020"
      - "8030:8030"
      - "8040:8040"
    depends_on:
      - ipfs
      - postgres
    environment:
      postgres_host: postgres
      postgres_user: graph-node
      postgres_pass: let-me-in
      postgres_db: graph-node
      ipfs: "ipfs:5001"
      GRAPH_ETH_CALL_BY_NUMBER: 1
      GRAPH_ALLOW_NON_DETERMINISTIC_IPFS: 1
      ethereum: "mainnet:archive,traces:https://a.api.s0.t.hmny.io"
      RUST_LOG: info
  ipfs:
    container_name: ipfs
    image: ipfs/go-ipfs:v0.4.23
    ports:
      - "5001:5001"
    volumes:
      - ./data/ipfs:/data/ipfs
  postgres:
    image: postgres
    ports:
      - "5432:5432"
    command: ["postgres", "-cshared_preload_libraries=pg_stat_statements"]
    environment:
      POSTGRES_USER: graph-node
      POSTGRES_PASSWORD: let-me-in
      POSTGRES_DB: graph-node
    volumes:
      - ./data/postgres:/var/lib/postgresql/data

 

 

and run your indexer node

 

docker-compose up -d
Creating network "thegraph_default" with the default driver
Creating ipfs ...
Creating postgres ...
Creating postgres done
Creating ipfs ... done
Creating indexer ... 
Creating indexer ... done

 

 

docker logs hmy_indexer -f should show the indexer synching with the harmony chain

 

docker logs hmy_indexer -f
Jul 29 05:33:22.849 INFO Graph Node version: 0.23.1 (2021-06-23)
Jul 29 05:33:22.861 INFO Generating configuration from command line arguments
Jul 29 05:33:22.909 INFO Starting up
Jul 29 05:33:22.911 INFO Trying IPFS node at: http://ipfs:5001/
Jul 29 05:33:22.928 INFO Creating transport, capabilities: archive, traces, url: https://api.s0.pops.one, provider: mainnet-rpc-0
Jul 29 05:33:22.948 INFO Successfully connected to IPFS node at: http://ipfs:5001/
Jul 29 05:33:23.680 INFO Connecting to Postgres, weight: 1, conn_pool_size: 10, url: postgresql://graph-node:HIDDEN_PASSWORD@postgres:5432/graph-node, pool: main, shard: primary
Jul 29 05:33:23.716 INFO Pool successfully connected to Postgres, pool: main, shard: primary, component: Store
Jul 29 05:33:23.721 INFO Setting up fdw, pool: main, shard: primary, component: ConnectionPool
Jul 29 05:33:23.728 INFO Running migrations, pool: main, shard: primary, component: ConnectionPool
Jul 29 05:33:24.748 INFO Migrations finished, pool: main, shard: primary, component: ConnectionPool
Jul 29 05:33:24.748 INFO Mapping primary, pool: main, shard: primary, component: ConnectionPool
Jul 29 05:33:24.767 INFO Connecting to Ethereum to get network identifier, capabilities: archive, traces, provider: mainnet-rpc-0
Jul 29 05:33:25.030 INFO Connected to Ethereum, capabilities: archive, traces, network_version: 0x6357d2e0, provider: mainnet-rpc-0
Jul 29 05:33:25.117 INFO Creating LoadManager in disabled mode, component: LoadManager
Jul 29 05:33:25.119 INFO Starting block ingestors
Jul 29 05:33:25.119 INFO Starting block ingestor for network, network_name: mainnet
Jul 29 05:33:25.120 INFO Starting job runner with 1 jobs, component: JobRunner
Jul 29 05:33:25.126 INFO Starting JSON-RPC admin server at: http://localhost:8020, component: JsonRpcServer
Jul 29 05:33:25.130 INFO Starting GraphQL HTTP server at: http://localhost:8000, component: GraphQLServer
Jul 29 05:33:25.130 INFO Starting index node server at: http://localhost:8030, component: IndexNodeServer
Jul 29 05:33:25.130 INFO Started all subgraphs, component: SubgraphRegistrar
Jul 29 05:33:25.130 INFO Starting metrics server at: http://localhost:8040, component: MetricsServer
Jul 29 05:33:25.131 INFO Starting GraphQL WebSocket server at: ws://localhost:8001, component: SubscriptionServer
Jul 29 05:33:25.258 INFO Downloading latest blocks from Ethereum. This may take a few minutes..., provider: mainnet-rpc-0, component: BlockIngestor
Jul 29 05:33:33.600 INFO Syncing 4 blocks from Ethereum., code: BlockIngestionStatus, blocks_needed: 4, blocks_behind: 4, latest_block_head: 12886125, current_block_head: 12886121, provider: mainnet-rpc-0, component: BlockIngestor
Jul 29 05:33:35.252 INFO Syncing 1 blocks from Ethereum., code: BlockIngestionStatus, blocks_needed: 1, blocks_behind: 1, latest_block_head: 12886126, current_block_head: 12886125, provider: mainnet-rpc-0, component: BlockIngestor

 

 

A few component are installed

Management: https://localhost:8020/ where subgraph are being created/deployed/deleted

Metrics / playground: https://localhost:8030/​

Visit your playground using the URL http://127.0.0.1:8030/graphql/playground and start playing around with graphQL API.

An example of query you can use to show subgraph currently being indexed would be :

query {
  indexingStatuses {
    subgraph
    entityCount
    fatalError {
      handler
    }
    nonFatalErrors {
      handler
    }
    chains {
      network
      latestBlock {
        number
      }
      chainHeadBlock {
        number
      }
      lastHealthyBlock {
        number
      }
    }
  }
}

 

 

Right now of course, the result is empty

 

{
  "data": {
    "indexingStatuses": []
  }
}

 

Our first subgraph

lets use blocklytics/ethereum-blocks subgraph as example

git clone https://github.com/blocklytics/ethereum-blocks
cd ethereum-blocks

 

Edit package.json file and add these lines

 

"create-harmony": "graph create --node http://localhost:8020 harmony/blocks",
"deploy-harmony": "graph deploy --node http://localhost:8020 --ipfs http://localhost:5001 harmony/blocks",

 

It is highly recommended to minimize the number of blocks to be indexed to avoid putting load on the RPCs and to speed up the usage of your subgraph/application

Update the manifest

Update the manifest subgraph.yaml file datasources[0]['network'] from rinkeby to mainnet or testnet accordingly to how you edited the network in your docker-compose.yaml if there is no need to index the entire blockchain, you can add an attribute startBlock to speed up the sync : datasources[0]['source']['startBlock']

Also, update the subgraph.yaml apiVersion: 0.0.5

It is highly recommended to minimize the number of blocks to be indexed to avoid putting load on the RPCs and to speed up the usage of your subgraph/application

Create and deploy the subgraph

 

yarn codegen
yarn build
yarn create-harmony 
yarn deploy-harmony

 

 

Sync begins and you are good to query your subgraph http://localhost:8000/subgraphs/name/harmony/blocks/graphql​

Note that the above example query should now show your something similar to the below

{
  "data": {
    "indexingStatuses": [
      {
        "chains": [
          {
            "chainHeadBlock": {
              "number": "12887470"
            },
            "lastHealthyBlock": null,
            "latestBlock": {
              "number": "10701810"
            },
            "network": "testnet"
          }
        ],
        "entityCount": "1812",
        "fatalError": null,
        "nonFatalErrors": [],
        "subgraph": "QmVDqqTJZM3ZHizSubG2H5b1vQ1Jp7iMD6Sc94A9zyRnAK"
      }
    ]
  }
}

 

 

data['indexingStatuses'][0]['chains'][0]['latestBlock']['number'] will indicate the last block synched