Akash Quick Start

SubQuery TeamAbout 5 min

Akash Quick Start

Goals

The goal of this quick start guide is to index all reward transactionsopen in new window for delegators in the Akash networkopen in new window.

Info

The Akash network is a chain based on the Cosmos SDK, which means you can index chain data via the standard Cosmos RPC interface.

Before we begin, make sure that you have initialised your project using the provided steps in the Start Here section. You must complete the suggested 4 stepsopen in new window for Cosmos users.

In every SubQuery project, there are 3 key files to update. Let's begin updating them one by one.

Tips

The final code of this project can be found hereopen in new window.

1. Your Project Manifest File

The Project Manifest (project.yaml) file is an entry point to your project. It defines most of the details on how SubQuery will index and transform the chain data. For Cosmos chains, there are four types of mapping handlers (and you can have more than one in each project):

BlockHanders: On each and every block, run a mapping function
TransactionHandlers: On each and every transaction, run a mapping function
MessageHandlers: On each and every message that matches optional filter criteria, run a mapping function
EventHanders: On each and every event that matches optional filter criteria, run a mapping function

Note that the manifest file has already been set up correctly and doesn’t require significant changes, but you need to change the datasource handlers. This section lists the triggers that the manifest file looks for on the blockchain to start indexing.

dataSources:
  - kind: cosmos/Runtime
    startBlock: 11364001
    mapping:
      file: ./dist/index.js
      handlers:
        - handler: handleReward
          kind: cosmos/EventHandler
          filter:
            type: withdraw_rewards
            messageFilter:
              type: "/cosmos.distribution.v1beta1.MsgWithdrawDelegatorReward"

In the code above, we have defined a single handler, handleReward, that will be executed whenever a withdraw_rewards type is detected within a MsgWithdrawDelegatorReward type message. This handler is used to track the rewards transactions of delegators in the Akash network.

Check out our Manifest File documentation to get more information about the Project Manifest (project.yaml) file.

2. Update Your GraphQL Schema File

The schema.graphql file determines the shape of the data that you are using SubQuery to index, hence it's a great place to start. The shape of your data is defined in a GraphQL Schema file with various GraphQL entities.

For this project, you'll need to modify your schema.graphql file as follows. Since we're indexing all reward transactionsopen in new window for delegators in the Akash network, we have a DelegatorReward entity that comprises a number of properties, including reward amount, delegator information, validator's address, and so forth. We also have a Delegator entity, which keeps track of the total rewards of each delegator.

type DelegatorReward @entity {
  id: ID!
  blockHeight: BigInt
  txHash: String
  feeDenomination: String
  feeAmount: BigInt
  rewardAmount: BigInt!
  delegator: Delegator!
  validatorAddress: String
}

type Delegator @entity {
  id: ID!
  totalRewards: BigInt!
}

Important

When you make any changes to the schema file, do not forget to regenerate your types directory.

yarn codegen

npm run-script codegen

You will find the generated models in the /src/types/models directory.

As you're creating a new CosmWasm based project, this command will also generate types for your listed protobufs and save them into src/types directory, providing you with more typesafety. Read about how this is done in Cosmos Codegen from CosmWasm Protobufs.

Check out our GraphQL Schema documentation to get more information on schema.graphql file.

Now that you have made essential changes to the GraphQL Schema file, let’s go ahead with the next configuration.

3. Add a Mapping Function

Mapping functions determine how chain data is transformed into the optimised GraphQL entities that you previously defined in the schema.graphql file.

Navigate to the default mapping function in the src/mappings directory and update your mapping files to match the following (note the additional imports):

import assert from "assert";
import { DelegatorReward, Delegator } from "../types";
import {
  CosmosEvent,
  CosmosBlock,
  CosmosMessage,
  CosmosTransaction,
} from "@subql/types-cosmos";

export async function handleReward(event: CosmosEvent): Promise<void> {
  logger.info(
    `New Reward Withdraw event at block ${event.block.header.height.toString()}`
  );

  const recordAmountString = event.event.attributes.find(
    (a) => a.key === "amount"
  )?.value;
  const validatorAddress = event.event.attributes.find(
    (a) => a.key === "validator"
  )?.value;
  const delegatorAddress = event.tx.tx.events
    .find((e) => e.type === "coins_received")
    ?.attributes.find((a) => a.key === "receiver")?.value;

  var rewardBigInt = BigInt(0);
  if (recordAmountString && Array.from(recordAmountString)[0] != "0") {
    rewardBigInt = BigInt(recordAmountString.split("u")[0]);
  }

  // Confirm we have all required values
  assert(
    rewardBigInt && validatorAddress && delegatorAddress,
    "No reward or no msg found"
  );

  const rewardRecord = DelegatorReward.create({
    id: event.tx.hash,
    blockHeight: BigInt(event.block.block.header.height),
    txHash: event.tx.hash,
    feeDenomination: event.tx.decodedTx.authInfo.fee?.amount[0].denom,
    feeAmount: event.tx.decodedTx.authInfo.fee?.amount[0].amount
      ? BigInt(event.tx.decodedTx.authInfo.fee?.amount[0].amount)
      : undefined,
    rewardAmount: rewardBigInt,
    delegatorId: delegatorAddress,
    validatorAddress: validatorAddress,
  });

  await handleDelegator(rewardRecord.rewardAmount, rewardRecord.delegatorId);
  await rewardRecord.save();
}

async function handleDelegator(reward: bigint, delegatorAddress: string) {
  let delegatorRecord = await Delegator.get(delegatorAddress);

  if (!delegatorRecord) {
    // Create new Delegator record
    delegatorRecord = Delegator.create({
      id: delegatorAddress,
      totalRewards: reward,
    });
    logger.info(
      "New delegator" + delegatorAddress + "with reward" + reward.toString()
    );
  } else {
    // Update delegators total
    delegatorRecord.totalRewards = delegatorRecord.totalRewards + reward;
  }
  await delegatorRecord.save();
}

In the Akash SubQuery project, we have two main functions, namely handleReward and handleDelegator, that were defined in the src/mappings/mappingHandlers.ts file.

The handleReward function is triggered when a withdraw_rewards type event is detected. It receives an event of type CosmosEvent, logs a message to the console for debugging purposes, and then tries to extract key data points such as the reward amount, validator address, and delegator address from the event.event.attributes (Cosmos events code attributes as an array of key-value pairs).

It then uses these attributes to create a DelegatorReward object, recording the reward amount and validator address associated with each reward withdrawal event. This object is subsequently saved in the GraphQL entities that we previously defined in the schema.graphql file.

The handleDelegator function is invoked within the handleReward function. This function is responsible for managing the Delegator entity. If a delegator does not already exist in the GraphQL entities, a new one is created with the reward from the current transaction. If the delegator already exists, the total rewards for the delegator are updated by adding the current reward.

This way, we're able to track all delegator rewards on the Akash network, along with the validator from whom the reward came. It's crucial to note that the handleDelegator function handles the Delegator entity creation and updates, whilst the handleReward function creates the DelegatorReward entity.

Check out our Mappings documentation and get information on the mapping functions in detail.

4. Build Your Project

Next, build your work to run your new SubQuery project. Run the build command from the project's root directory as given here:

yarn build

npm run-script build

Important

Whenever you make changes to your mapping functions, you must rebuild your project.

Now, you are ready to run your first SubQuery project. Let’s check out the process of running your project in detail.

5. Run Your Project Locally with Docker

Whenever you create a new SubQuery Project, first, you must run it locally on your computer and test it and using Docker is the easiest and quickest way to do this.

The docker-compose.yml file defines all the configurations that control how a SubQuery node runs. For a new project, which you have just initialised, you won't need to change anything.

However, visit the Running SubQuery Locally to get more information on the file and the settings.

Run the following command under the project directory:

yarn start:docker

npm run-script start:docker

Note

It may take a few minutes to download the required images and start the various nodes and Postgres databases.

6. Query your Project

Next, let's query our project. Follow these three simple steps to query your SubQuery project:

Open your browser and head to http://localhost:3000.
You will see a GraphQL playground in the browser and the schemas which are ready to query.
Find the Docs tab on the right side of the playground which should open a documentation drawer. This documentation is automatically generated and it helps you find what entities and methods you can query.

Try the following queries to understand how it works for your new SubQuery starter project. Don’t forget to learn more about the GraphQL Query language.

{
  query {
    delegatorReward(first: 1) {
      nodes {
        id
        delegatorAddress
        validatorAddress
        rewardAmount
      }
    }
  }
}

You will see the result similar to below:

{
  "data": {
    "query": {
      "delegatorRewards": {
        "totalCount": 1,
        "nodes": [
          {
            "id": "808FED7F3FE680EEF8E005EC1927C0CF00D2975E4B26CEE7A098D5DA7DEA8217",
            "delegatorAddress": "akash1ckc4z334rfpdcqdz5a85mdtaktt2dtkm58783c5",
            "validatorAddress": "akashvaloper14kn0kk33szpwus9nh8n87fjel8djx0y0uzn073",
            "rewardAmount": "1440293uakt"
          }
        ]
      }
    }
  }
}

What’s Next?

Congratulations! You have now a locally running SubQuery project that accepts GraphQL API requests for indexing Akash delegator rewards.

Tip

Find out how to build a performant SubQuery project and avoid common mistakes in Project Optimisation.

Click here to learn what should be your next step in your SubQuery journey.

Akash Quick Start

# Akash Quick Start

# Goals

# 1. Your Project Manifest File

# 2. Update Your GraphQL Schema File

# 3. Add a Mapping Function

# 4. Build Your Project

# 5. Run Your Project Locally with Docker

# 6. Query your Project

# What’s Next?

Akash Quick Start

Goals

1. Your Project Manifest File

2. Update Your GraphQL Schema File

3. Add a Mapping Function

4. Build Your Project

5. Run Your Project Locally with Docker

6. Query your Project

What’s Next?