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On-chain Interactions

Welcome to FIXeS on-chain interactions documentation

Overview

In this section, we provide detailed instructions on interacting with the FIXeS contract on the blockchain. To effectively interact with the FIXeS contract, users should possess a basic understanding of blockchain technology, smart contracts, and the Flow blockchain that the FIXeS contract is deployed on.

Getting Started

You can get the contract address of FIXeS here: Are the contracts open-sourced?

For front-end or NodeJS projects, we have prepared a more user-friendly way of integration. You can follow this guide to get started.

Requirements

  • Node version v16.0.0 or higher.

  • FCL(Flow Client Library) installation: Official Doc

Dependencies Installation

Install FIXeS contracts to your application via npm, yarn, or pnpm

npm i @fixes/contracts
yarn add @fixes/contracts
pnpm add @fixes/contracts

Include *.cdc assets for your project

Interacting with the Flow blockchain requires using transactions/scripts, and all necessary ones are included in @fixes/contracts package. However, to use them in your application, you need to make sure that your building tool can recognize this file extension first.

Using Vite as an example, you need to add this field in vite.config.js: 

{
    assetsInclude: ["**/*.cdc"],
}

How to quickly set up FCL ?

FCL is an all-in-one JS library to interact with Flow blockchain, If you are not familiar with it, you can refer to the code below.

Here is an independent wrapped class of FCL :

/// This is a TypeScript example
/// If some type is not found, you can directly change it to any

import * as fcl from "@onflow/fcl";
import type { Account, TransactionStatus } from "@onflow/typedefs";

export type NetworkType = "mainnet" | "testnet" | "emulator";

let isGloballyInited = false;
let globallyPromise = null;

export class FlowService {
  public readonly network: NetworkType;
  private readonly flowJSON: object;

  /**
   * Initialize the Flow SDK
   */
  constructor(flowJSON: object) {
    this.network =
      (import.meta.env.PUBLIC_FLOW_NETWORK as NetworkType) ?? "emulator";
    this.flowJSON = flowJSON;
  }

  async onModuleInit() {
    if (isGloballyInited) return;

    const cfg = fcl.config();
    // Required
    await cfg.put("flow.network", this.network);
    // Set the maximum of gas limit
    await cfg.put("fcl.limit", 9999);

    // Note: If you don't need to be compatible with an FCL-compatible wallet
    // you don't need to configure these two parameters.
    await cfg.put("app.detail.title", "App Title");
    await cfg.put("app.detail.icon", "App Icon URL");

    switch (this.network) {
      case "mainnet":
        // Required
        await cfg.put(
          "accessNode.api",
          import.meta.env.PUBLIC_MAINNET_ENDPOINT ??
            "https://mainnet.onflow.org"
        );

        // Note: If you don't need to be compatible with an FCL-compatible wallet
        // you don't need to configure these two following parameters.
        await cfg.put(
          "discovery.wallet",
          "https://fcl-discovery.onflow.org/authn"
        );
        await cfg.put(
          "discovery.authn.endpoint",
          "https://fcl-discovery.onflow.org/api/authn"
        );
        break;
      case "testnet":
        // Required
        await cfg.put("accessNode.api", "https://testnet.onflow.org");

        // Note: If you don't need to be compatible with an FCL-compatible wallet
        // you don't need to configure these two following parameters.
        await cfg.put(
          "discovery.wallet",
          "https://fcl-discovery.onflow.org/testnet/authn"
        );
        await cfg.put(
          "discovery.authn.endpoint",
          "https://fcl-discovery.onflow.org/api/testnet/authn"
        );
        break;
      case "emulator":
        // Required
        await cfg.put("accessNode.api", "http://localhost:8888");

        // Note: If you don't need to be compatible with an FCL-compatible wallet
        // you don't need to configure these following parameters.
        await cfg.put("discovery.wallet", "http://localhost:8701/fcl/authn");
        break;
      default:
        throw new Error(`Unknown network: ${String(this.network)}`);
    }

    // Load Flow JSON
    await cfg.load({ flowJSON: this.flowJSON });

    isGloballyInited = true;
  }

  /**
   * Ensure the Flow SDK is initialized
   */
  private async ensureInited() {
    if (isGloballyInited) return;
    if (!globallyPromise) {
      globallyPromise = this.onModuleInit();
    }
    return await globallyPromise;
  }

  /**
   * Authenticate for current user
   * Only supported on the front-end.
   */
  async authenticate() {
    await this.ensureInited();
    fcl.authenticate();
  }

  /**
   * Logout
   * Only supported on the front-end.
   */
  unauthenticate() {
    fcl.unauthenticate();
  }

  /**
   * Get the current logged-in
   * Only supported on the front-end.
   */
  get currentUser() {
    return fcl.currentUser;
  }

  /**
   * Get account information
   */
  async getAccount(addr: string): Promise<Account> {
    await this.ensureInited();
    return await fcl.send([fcl.getAccount(addr)]).then(fcl.decode);
  }

  /**
   * General method of sending transaction
   */
  async sendTransaction(
    code: string,
    args: fcl.ArgumentFunction,
    mainAuthz?: fcl.FclAuthorization,
    extraAuthz?: fcl.FclAuthorization[]
  ) {
    await this.ensureInited();
    if (typeof mainAuthz !== "undefined") {
      return await fcl.mutate({
        cadence: code,
        args: args,
        proposer: mainAuthz,
        payer: mainAuthz,
        authorizations:
          (extraAuthz?.length ?? 0) === 0
            ? [mainAuthz]
            : [mainAuthz, ...extraAuthz],
      });
    } else {
      return await fcl.mutate({
        cadence: code,
        args: args,
      });
    }
  }

  /**
   * Get transaction status
   */
  async getTransactionStatus(
    transactionId: string
  ): Promise<TransactionStatus> {
    await this.ensureInited();
    return await fcl.tx(transactionId).onceExecuted();
  }

  /**
   * Get chain id
   */
  async getChainId() {
    await this.ensureInited();
    return await fcl.getChainId();
  }

  /**
   * Send transaction with single authorization
   */
  async onceTransactionSealed(
    transactionId: string
  ): Promise<TransactionStatus> {
    await this.ensureInited();
    return fcl.tx(transactionId).onceSealed();
  }

  /**
   * Get block object
   * @param blockId
   */
  async getBlockHeaderObject(blockId: string): Promise<fcl.BlockHeaderObject> {
    await this.ensureInited();
    return await fcl
      // eslint-disable-next-line @typescript-eslint/no-unsafe-argument
      .send([fcl.getBlockHeader(), fcl.atBlockId(blockId)])
      .then(fcl.decode);
  }

  /**
   * Send script
   */
  async executeScript<T>(
    code: string,
    args: fcl.ArgumentFunction,
    defaultValue: T
  ): Promise<T> {
    await this.ensureInited();
    try {
      const queryResult = await fcl.query({
        cadence: code,
        args,
      });
      return (queryResult as T) ?? defaultValue;
    } catch (e) {
      console.error(e);
      return defaultValue;
    }
  }
}

If you don't need to use an FCL-compatible wallet for on-chain interactions, you can use this Signer class:

import elliptic from "elliptic";
import { SHA3 } from "sha3";
import * as fcl from "@onflow/fcl";

import { FlowService } from "./flow.service";
// Here is the configuration file for fixes.
import flowJSON from "@fixes/contracts/flow.json" assert { type: "json" };

const ec = new elliptic.ec("p256");

export default class FlowSigner {
  private readonly flowService: FlowService;

  constructor(
    private readonly address: string,
    private readonly privateKeyHex: string,
    private readonly accountIndex: string
  ) {
    this.flowService = new FlowService(flowJSON);
  }

  /**
   * Send a transaction
   * @param code Cadence code
   * @param args Cadence arguments
   */
  async sendTransaction(code: string, args: fcl.ArgumentFunction) {
    return await this.flowService.sendTransaction(
      code,
      args,
      this._buildAuthorization()
    );
  }

  /**
   * Execute a script
   * @param code Cadence code
   * @param args Cadence arguments
   */
  async executeScript<T>(
    code: string,
    args: fcl.ArgumentFunction,
    defaultValue: T
  ): Promise<T> {
    return await this.flowService.executeScript(code, args, defaultValue);
  }

  /**
   * Build authorization
   */
  private _buildAuthorization() {
    const address = this.address;
    const accountIndex = this.accountIndex;
    const privateKey = this.privateKeyHex;
    return async (account) => {
      return {
        ...account,
        tempId: `${address}-${accountIndex}`,
        addr: fcl.sansPrefix(address),
        keyId: Number(accountIndex),
        signingFunction: (signable) => {
          return {
            addr: fcl.withPrefix(address),
            keyId: Number(accountIndex),
            signature: this._signWithKey(privateKey, signable.message),
          };
        },
      };
    };
  }

  /**
   * Sign a message with a private key
   */
  private _signWithKey(privateKey: string, msg: string) {
    const key = ec.keyFromPrivate(Buffer.from(privateKey, "hex"));
    const sig = key.sign(this._hashMsg(msg));
    const n = 32;
    const r = sig.r.toArrayLike(Buffer, "be", n);
    const s = sig.s.toArrayLike(Buffer, "be", n);
    return Buffer.concat([r, s]).toString("hex");
  }

  /**
   * Hash a message
   */
  private _hashMsg(msg: string) {
    const sha = new SHA3(256);
    sha.update(Buffer.from(msg, "hex"));
    return sha.digest();
  }
}

How to send a transaction to Flow blockchain or query data from Flow blockchain?

Here are some example codes. learn more from the official doc

In the following documentation, flow means an instence of flowSigner or flowService as the subject of function calls.

// FIXeS configure
import flowJSON from "@fixes/contracts/flow.json" assert { type: "json" };
// FIXeS Transactions
import txHeartbeatStaking from "@fixes/contracts/transactions/staking/heartbeat-staking.cdc?raw";
// FIXeS Scripts
import scResolveName from "@fixes/contracts/scripts/utils/resolve-name.cdc?raw";

import { FlowService } from "./flow.service";
import FlowSigner from "./Signer";

async function heartbeat(tickerName: string): Promise<string> {
    const flowSigner = new FlowSigner(signerAddr, signerPrivKey, signerKeyId);
    // If you want to directly use FCL-compatible wallets on the frontend,
    // you can also use flowService here, but you need to connect the wallet 
    // first using flowService.authenticate
    const txid = await flowSigner.sendTransaction(
      txHeartbeatStaking,
      (arg, t) => [arg(tickerName, t.String)]
    );
    return txid;
}

async function resolveAddressName(addr: string): Promise<string> {
    const flowService = new FlowService(flowJSON);
    return await flowService.executeScript(
        scResolveName,
        (arg, t) => [arg(addr, t.Address)]
        addr
    )
}

𝔉rc20 Interactions

🔯𝔉rc20

Fixes Inscription Interactions

🔡Fixes Inscription
PreviousQuery ReviewersNext𝔉rc20

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