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Field selection

setFields(options)​

Set the fields to be retrieved for data items of each supported type. The options object has the following structure:

{
  block?:       // field selector for block headers
  transaction?: // field selector for transactions
  receipt?:     // field selector for receipts
  input?:       // field selector for inputs
  output?:      // field selector for output
}

Every field selector is a collection of boolean fields that map to the fields of data items within the batch context iterables. Defining a field of a field selector of a given type and setting it to true will cause the processor to populate the corresponding field of all data items of that type. Here is a definition of a processor that requests hash and status fields for transactions and the contract field for receipts:

const dataSource = new DataSourceBuilder().setFields({
  transaction: {
    hash: true,
    status: true,
  },
  receipt: {
    contract: true,
  },
});

Same fields will be available for all data items of any given type, including the items accessed via nested references. Suppose we used the processor defined above to subscribe to some transactions as well as some receipts, and for each receipt we requested its parent transaction:

dataSource
  .addTransaction({
    // some transaction data requests
  })
  .addReceipt({
    // some receipt data requests

    transaction: true
  })
  .build();

After populating the convenience reference fields with augmentBlock() from @subsquid/fuel-objects, the contract field will be available both within the data items of the transactions iterable of block data and within the transaction items that provide parent transaction information for the receipts matching the addReceipt() data request:

run(dataSource, database, async (ctx) => {
  let blocks = ctx.blocks.map(augmentBlock)
  for (let block of blocks) {
    for (let txn of block.transactions) {
      let contract = txn.contract; // OK
    }
    for (let rec of block.receipts) {
      if (/* rec matches the data request */) {
        let recContract = rec.transaction.contract; // also OK!
      }
    }
  }
})

Some data fields, like hash for transactions, are enabled by default but can be disabled by setting a field of a field selector to false. For example, this code will not compile:

const dataSource = new DataSourceBuilder()
  .setFields({
    transaction: {
      hash: false,
    },
  })
  .build();

run(dataSource, database, async (ctx) => {
  for (let block of ctx.blocks) {
    for (let txn of block.transactions) {
      let signatures = txn.hash; // ERROR: no such field
    }
  }
});

Disabling unused fields will improve sync performance, as the fields' data will not be fetched from the Subsquid Network gateway.

Data item types and field selectors​

tip

Most IDEs support smart suggestions to show the possible field selectors. For VS Code, press Ctrl+Space.

Here we describe the data item types as functions of the field selectors. Unless otherwise mentioned, each data item type field maps to the eponymous field of its corresponding field selector. Item fields are divided into three categories:

  • Fields that are always added regardless of the setFields() call.
  • Fields that are enabled by default and can be disabled by setFields(). E.g. a hash field will be fetched for transactions by default, but can be disabled by setting hash: false within the transaction field selector.
  • Fields that can be requested by setFields().

Transaction​

Fields of Transaction data items may be requested by the eponymous fields of the field selector. Composite fields like inputContract are requested in their entirety by a single selector.

Here's a detailed description of possible Transaction fields:

Transaction {
  // independent of field selectors
  index: number

  // can be disabled with field selectors
  hash: string
  type: TransactionType
  status: Status

  // can be enabled with field selectors
  inputAssetIds?: string[]
  inputContracts?: string[]
  inputContract?: {
    utxoId: string
    balanceRoot: string
    stateRoot: string
    txPointer: string
    contractId: string
  }
  policies?: Policies
  scriptGasLimit?: bigint
  maturity?: number
  mintAmount?: bigint
  mintAssetId?: string
  mintGasPrice?: bigint
  txPointer?: string
  isScript: boolean
  isCreate: boolean
  isMint: boolean
  isUpgrade: boolean
  isUpload: boolean
  outputContract?: {
    inputIndex: number
    balanceRoot: string
    stateRoot: string
  }
  witnesses?: string[]
  receiptsRoot?: string
  script?: string
  scriptData?: string
  salt?: string
  storageSlots?: string[]
  rawPayload?: string
  bytecodeWitnessIndex?: number
  bytecodeRoot?: string
  subsectionIndex?: number
  subsectionsNumber?: number
  proofSet?: string[]
  upgradePurpose?: UpgradePurpose
}

  • transactionType field has the following type:

    type TransactionType =
      "Script" |
      "Create" |
      "Mint" |
      "Upgrade" |
      "Upload"

  • status field has the following type:

    type Status =
      SubmittedStatus |
      SuccessStatus |
      SqueezedOutStatus |
      FailureStatus

    Status can be one of the following:

    interface SubmittedStatus {
      type: "SubmittedStatus"
      time: bigint
    }

    interface SuccessStatus {
      type: "SuccessStatus"
      transactionId: string
      time: bigint
      programState?: ProgramState
    }

    interface SqueezedOutStatus {
      type: "SqueezedOutStatus"
      reason: string
    }

    interface FailureStatus {
      type: "FailureStatus"
      transactionId: string
      time: bigint
      reason: string
      programState?: ProgramState
      totalGas: bigint
      totalFee: bigint
    }

    ProgramState is defined as follows:

    interface ProgramState {
      returnType: "RETURN" | "RETURN_DATA" | "REVERT";
      data: string;
    }

  • policies field has the following interface:

    interface Policies {
      gasPrice?: bigint
      witnessLimit?: bigint
      maturity?: number
      maxFee?: bigint
    }

  • upgradePurpose field is of type ConsensusParametersPurpose | StateTransitionPurpose, where the types are defined as:

    interface ConsensusParametersPurpose {
      type: 'ConsensusParametersPurpose'
      witnessIndex: number
      checksum: string
    }

    interface StateTransitionPurpose {
      type: 'StateTransitionPurpose'
      root: string
    }

Receipt​

Fields of Receipt data items may be requested by the eponymous fields of the field selector. Here's a detailed description of possible Receipt fields:

Receipt {
  // independent of field selectors
  index: number
  transactionIndex: number

  // can be disabled with field selectors
  receiptType: ReceiptType

  // can be enabled with field selectors
  contract?: string
  pc?: bigint
  is?: bigint
  to?: string
  toAddress?: string
  amount?: bigint
  assetId?: string
  gas?: bigint
  param1?: bigint
  param2?: bigint
  val?: bigint
  ptr?: bigint
  digest?: string
  reason?: bigint
  ra?: bigint
  rb?: bigint
  rc?: bigint
  rd?: bigint
  len?: bigint
  result?: bigint
  gasUsed?: bigint
  data?: string
  sender?: string
  recipient?: string
  nonce?: string
  contractId?: string
  subId?: string
}

  • receiptType has the following type:

    type ReceiptType =
      | "CALL"
      | "RETURN"
      | "RETURN_DATA"
      | "PANIC"
      | "REVERT"
      | "LOG"
      | "LOG_DATA"
      | "TRANSFER"
      | "TRANSFER_OUT"
      | "SCRIPT_RESULT"
      | "MESSAGE_OUT"
      | "MINT"
      | "BURN";

Input​

Input data items can be of types InputCoin, InputContract or InputMessage. Each type has its own set of fields. To access the type-specific fields, narrow down the type by asserting the value of the type field, e.g.

if (input.type === "InputCoin") {
  // use InputCoin-specific fields here
}

To get a name of a field selector field, apply a type prefix to a capitalized name of the data item field, e.g.

  • amount field of InputCoin input items is requested by coinAmount: true;
  • witnessIndex field of InputMessage input items is requested by messageWitnessIndex: true etc.

All Input* data types have transactionIndex, index and type fields. These cannot be disabled. There aren't any fields that are enabled by default and can be disabled.

InputCoin data items may have the following fields:

interface InputCoin {
  type: "InputCoin";
  index: number;
  transactionIndex: number;
  utxoId: string;
  owner: string;
  amount: bigint;
  assetId: string;
  txPointer: string;
  witnessIndex: number;
  predicateGasUsed: bigint;
  predicate: string;
  predicateData: string;
}

InputContract data items may have the following fields:

interface InputContract {
  type: "InputContract";
  index: number;
  transactionIndex: number;
  utxoId: string;
  balanceRoot: string;
  stateRoot: string;
  txPointer: string;
  contractId: string;
}

InputMessage data items may have the following fields:

InputMessage {
  type: "InputMessage";
  index: number;
  transactionIndex: number;
  sender: string;
  recipient: string;
  amount: bigint;
  nonce: string;
  witnessIndex: number;
  predicateGasUsed: bigint;
  data: string;
  predicate: string;
  predicateData: string;
}

It is possible to request more than one type of input in the same data request. For example, to request all inputs of type InputCoin and InputContract:

dataSource
  .addInput({
    type: ["InputCoin", "InputContract"],
  })
  .build();

Output​

Output data items can be of types CoinOutput, ContractOutput, ChangeOutput, VariableOutput or 'ContractCreated'. Each type has its own set of fields. To access the type-specific fields, narrow down the type by asserting the value of the type field, e.g.

if (output.type === "CoinOutput") {
  // use CoinOutput-specific fields here
}

To get a name of a field selector field, apply a type prefix to a capitalized name of the data item field, e.g.

  • to field of CoinOutput items is requested by coinTo: true;
  • inputIndex field of ContractOutput items is requested by contractInputIndex: true;
  • amount field of ChangeOutput items is requested by changeAmount: true;
  • assetId field of VariableOutput items is requested by variableAssetId: true;
  • stateRoot field of ContractCreated items is requested by contractCreatedStateRoot: true etc.

All output data types have transactionIndex, index and type fields. These cannot be disabled. There aren't any fields that are enabled by default and can be disabled.

CoinOutput data items may have the following fields:

CoinOutput {
  type: 'CoinOutput'
  index: number
  transactionIndex: number
  to: string
  amount: bigint
  assetId: string
}

ContractOutput data items may have the following fields:

ContractOutput {
  type: "ContractOutput";
  index: number;
  transactionIndex: number;
  inputIndex: number;
  balanceRoot: string;
  stateRoot: string;
}

ChangeOutput data items may have the following fields:

ChangeOutput {
  type: 'ChangeOutput'
  index: number
  transactionIndex: number
  to: string
  amount: bigint
  assetId: string
}

VariableOutput data items may have the following fields:

VariableOutput {
  type: 'VariableOutput'
  index: number
  transactionIndex: number
  to: string
  amount: bigint
  assetId: string
}

ContractCreated data items may have the following fields:

ContractCreated {
  type: 'ContractCreated'
  index: number
  transactionIndex: number
  contract: string
  stateRoot: string
}

Block header​

BlockHeader data items may have the following fields:

export interface BlockHeader {
	// independent of field selectors
  hash: string
  height: number

  // can be disabled with field selectors
  time: bigint

  // can be enabled with field selectors
  daHeight: bigint
  transactionsRoot: string
  transactionsCount: number
  messageReceiptCount: number
  prevRoot: string
  applicationHash: string
  eventInboxRoot: string
  consensusParametersVersion: number
  stateTransitionBytecodeVersion: number
  messageOutboxRoot: string
}

Request the fields with eponymous field request flags.

A complete example​

import { run } from "@subsquid/batch-processor";
import { augmentBlock } from "@subsquid/fuel-objects";
import { DataSourceBuilder } from "@subsquid/fuel-stream";
import { TypeormDatabase } from "@subsquid/typeorm-store";
import { Contract } from "./model";

const dataSource = new DataSourceBuilder()
  .setGateway("https://v2.archive.subsquid.io/network/fuel-testnet")
  .setGraphql({
    url: "https://testnet.fuel.network/v1/graphql",
  })
  .setFields({
    transaction: {
      hash: false,
      isMint: true,
    },
    receipt: {
      amount: true,
      gas: true,
    },
    input: {
      coinOwner: true,
      contractStateRoot: true,
    },
    output: {
      coinTo: true,
      contractCreatedStateRoot: true,
    },
    block: {
      daHeight: true
    }
  })
  .addTransaction({
    type: ['Mint', 'Script'],
    inputs: true,
    range: { from: 1_000_000 }
  })
  .addReceipt({
    type: ['LOG_DATA']
  })
  .addInput({
    type: ['InputCoin', 'InputContract']
  })
  .addOutput({
    type: ['CoinOutput', 'ContractCreated'],
    transaction: true
  })
  .build()