Lesson 14 - Dynamic SVG NFT on Sepolia - price always 0

[DylanMaas]

Hi,

All my code seems to be working (contract, deployments etc.)

However, with regards to minting the dynamic SVG NFT, I always seem to get a price of 0, which means I always get the frowny smiley.

While doing the unit tests, the contract actually worked in the rigth way, so I am thinking it has something to do with the MockV3Aggregator, but I can't find what. Here is my code:

Contract

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.8;

import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "base64-sol/base64.sol";
import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";

contract DynamicSvgNft is ERC721 {
    // mint
    // store our SVG information somewhere
    // Show x image, or Y image based on Z

    uint256 private s_tokenCounter;
    string private i_lowImageUri;
    string private i_highImageUri;
    string private constant base64EncodedSvgPrefix = "data:image/svg+xml;base64,";
    AggregatorV3Interface internal immutable i_priceFeed;
    mapping(uint256 => int256) public s_tokenIdToHighValue;

    event CreatedNft(uint256 indexed tokenId, int256 highValue);

    constructor(
        address priceFeedAddress,
        string memory lowSvg,
        string memory highSvg
    ) ERC721("Dynamic SVG NFT", "DSN") {
        s_tokenCounter = 0;
        i_lowImageUri = svgToImageUri(lowSvg);
        i_highImageUri = svgToImageUri(highSvg);
        i_priceFeed = AggregatorV3Interface(priceFeedAddress);
    }

    // We can't just paste the SVG code, since this will not generate an image URI.
    // Hence, we need a function to convert this SVG code to an image URI
    // For this, we need to use Base64
    // We need

    function svgToImageUri(string memory svg) public pure returns (string memory) {
        // we are gonna give this function an SVG, passed in from our constructor
        // we are gonna return a string, the base64 encoded URL
        string memory svgBase64Encoded = Base64.encode(bytes(string(abi.encodePacked(svg))));
        return string(abi.encodePacked(base64EncodedSvgPrefix, svgBase64Encoded));
        // we are encoding them to our bytes implementation, and then typecasting them back from bytes to strings (see notes in Word)
    }

    function mintNft(int256 highValue) public {
        s_tokenIdToHighValue[s_tokenCounter] = highValue;
        _safeMint(msg.sender, s_tokenCounter);
        s_tokenCounter = s_tokenCounter + 1;
        // must be beneath the function
        emit CreatedNft(s_tokenCounter, highValue);
    }

    function _baseURI() internal pure override returns (string memory) {
        return "data:application/json;base64,";
    }

    function tokenURI(uint256 tokenId) public view override returns (string memory) {
        address owner = _ownerOf(tokenId);
        if (owner == address(0)) {
            revert ERC721NonexistentToken(tokenId);
        }

        (, int256 price, , , ) = i_priceFeed.latestRoundData();

        string memory imageURI = i_lowImageUri;
        if (price >= s_tokenIdToHighValue[tokenId]) {
            imageURI = i_highImageUri;
        }

        return
            string(
                abi.encodePacked(
                    _baseURI(),
                    Base64.encode(
                        bytes(
                            abi.encodePacked(
                                '{"name":"',
                                name(), // You can add whatever name here
                                '", "description":"An NFT that changes based on the Chainlink Feed", ',
                                '"attributes": [{"trait_type": "coolness", "value": 100}], "image":"',
                                imageURI,
                                '"}'
                            )
                        )
                    )
                )
            );
    }

    function getLowSVG() public view returns (string memory) {
        return i_lowImageUri;
    }

    function getHighSVG() public view returns (string memory) {
        return i_highImageUri;
    }

    function getPriceFeed() public view returns (AggregatorV3Interface) {
        return i_priceFeed;
    }

    function getTokenCounter() public view returns (uint256) {
        return s_tokenCounter;
    }
}

Unit Test (all succesfull)

const { deployments, ethers, network } = require("hardhat")
const { assert, expect } = require("chai")
const { developmentChains } = require("../../helper-hardhat-config")
const { check } = require("prettier")

const lowSVGImageuri =
    "data:image/svg+xml;base64,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"
const highSVGimageUri =
    "data:image/svg+xml;base64,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"

const highTokenUri =
    "data:application/json;base64,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"
const lowTokenUri =
    "data:application/json;base64,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"

!developmentChains.includes(network.name)
    ? describe.skip
    : describe("Dynamic SVG NFT Unit Tests", function () {
          let dynamicSvgNft, signer, mockV3Aggregator

          beforeEach(async () => {
              const accounts = await ethers.getSigners()
              signer = accounts[0]
              await deployments.fixture(["all"])

              const dynamicSvgNftDeployment = await deployments.get("DynamicSvgNft")
              dynamicSvgNft = await ethers.getContractAt(
                  dynamicSvgNftDeployment.abi,
                  dynamicSvgNftDeployment.address,
                  signer,
              )
              const mockV3AggregatorDeployment = await deployments.get("MockV3Aggregator")
              mockV3Aggregator = await ethers.getContractAt(
                  mockV3AggregatorDeployment.abi,
                  mockV3AggregatorDeployment.address,
                  signer,
              )
          })
          it("contract was deployed", async () => {
              assert(dynamicSvgNft.target)
          })

          describe("Constructor", function () {
              it("Sets starting values correctly", async () => {
                  const lowSvg = await dynamicSvgNft.getLowSVG()
                  const highSvg = await dynamicSvgNft.getHighSVG()
                  const priceFeed = await dynamicSvgNft.getPriceFeed()
                  assert.equal(lowSvg, lowSVGImageuri)
                  assert.equal(highSvg, highSVGimageUri)
                  assert.equal(priceFeed, mockV3Aggregator.target)
              })
          })

          describe("mintNft", function () {
              it("emits an event and creates an NFT", async () => {
                  const highValue = ethers.parseEther("1") // 1 dollar per ether
                  await expect(dynamicSvgNft.mintNft(highValue)).to.emit(
                      dynamicSvgNft,
                      "CreatedNft",
                  )
                  const tokenCounter = await dynamicSvgNft.getTokenCounter()
                  assert.equal(tokenCounter.toString(), "1")
                  const tokenURI = await dynamicSvgNft.tokenURI(0)
                  assert.equal(tokenURI, highTokenUri)
              })
              it("shifts the token URI to lower when the price doesn't surpass the highvalue", async () => {
                  const highValue = ethers.parseEther("100000000") // 100,000,000 dollar per ether
                  txResponse = await dynamicSvgNft.mintNft(highValue)
                  txResponse.wait(1)
                  const tokenURI = await dynamicSvgNft.tokenURI(0)
                  assert.equal(tokenURI, lowTokenUri)
              })
          })

          describe("tokenURI", function () {
              it("Reverts if the `tokenId` doesn't have a current owner", async () => {
                  const highValue = ethers.parseEther("100000000")
                  txResponse = await dynamicSvgNft.mintNft(highValue)
                  txResponse.wait(1)
                  await expect(dynamicSvgNft.tokenURI(1)).to.be.revertedWithCustomError(
                      dynamicSvgNft,
                      "ERC721NonexistentToken",
                  )
              })
          })
      })

Deploy scripts - 03 deploy dynamic svg nft

const { networkConfig, developmentChains } = require("../helper-hardhat-config")
const { network, ethers } = require("hardhat")
const { verify } = require("../utils/verify")
const fs = require("fs")

module.exports = async ({ getNamedAccounts, deployments }) => {
    const { deploy, log } = deployments
    const { deployer } = await getNamedAccounts()
    const chainId = network.config.chainId

    //constructor variables
    let ethUsdPriceFeedAddress
    if (developmentChains.includes(network.name)) {
        const ethUsdAggregator = await deployments.get("MockV3Aggregator")
        ethUsdPriceFeedAddress = ethUsdAggregator.address
    } else {
        ethUsdPriceFeedAddress = networkConfig[chainId]["ethUsdPriceFeed"]
    }

    const lowSvg = await fs.readFileSync("./images/dynamicNft/frown.svg", { encoding: "utf8" })
    const highSvg = await fs.readFileSync("./images/dynamicNft/happy.svg", { encoding: "utf8" })

    // now let's deploy the contract

    const args = [ethUsdPriceFeedAddress, lowSvg, highSvg]

    const dynamicSvgNft = await deploy("DynamicSvgNft", {
        from: deployer,
        args: args,
        log: true,
        waitConfirmations: network.config.blockConfirmations || 1,
    })
    log(`DynamicSvgNft deployed at ${dynamicSvgNft.address}`)

    if (!developmentChains.includes(network.name) && process.env.ETHERSCAN_API_KEY) {
        log("Verifying...")
        await verify(dynamicSvgNft.address, args)
    }
    log("------------------------------------------------")
}

module.exports.tags = ["all", "dynamicsvg", "main"]

Deploy scripts - 04 deploy mint

const { networkConfig, developmentChains } = require("../helper-hardhat-config")
const { network, ethers } = require("hardhat")
const { verify } = require("../utils/verify")
const fs = require("fs")

module.exports = async ({ getNamedAccounts, deployments }) => {
    const accounts = await ethers.getSigners()
    signer = accounts[0]

    // // Basic NFT
    // const basicNftDeployment = await deployments.get("BasicNft")
    // basicNft = await ethers.getContractAt(
    //     basicNftDeployment.abi,
    //     basicNftDeployment.address,
    //     signer,
    // )
    // const basicMintTx = await basicNft.mintNft()
    // await basicMintTx.wait(1)
    // console.log(`Basic NFT with index 0 has tokenURI: ${await basicNft.tokenURI(0)}`)

    // // Random IPFS NFT
    // const randomIpfsNftDeployment = await deployments.get("RandomIpfsNft")
    // randomIpfsNft = await ethers.getContractAt(
    //     randomIpfsNftDeployment.abi,
    //     randomIpfsNftDeployment.address,
    //     signer,
    // )
    // const mintFee = await randomIpfsNft.getMintFee()
    // const randomIpfsNftMintTx = await randomIpfsNft.requestNft({ value: mintFee.toString() })
    // const randomIpfsNftMintTxReceipt = randomIpfsNftMintTx.wait(1)

    // // Need to listen for response
    // await new Promise(async (resolve, reject) => {
    //     setTimeout(() => reject("Timeout: 'NFTMinted' event did not fire"), 600000) // 10 minutes
    //     // setup listener for our event
    //     randomIpfsNft.once("NftMinted", async () => {
    //         console.log(
    //             `Random IPFS NFT with index 0 has tokenURI: ${await randomIpfsNft.tokenURI(0)}`,
    //         )
    //         resolve()
    //     })

    //     if (developmentChains.includes(network.name)) {
    //         requestId = 1 // const requestId = randomIpfsNftMintTxReceipt.events[1].args.requestId
    //         const vrfCoordinatorV2MockDeployment = await deployments.get("VRFCoordinatorV2Mock")
    //         vrfCoordinatorV2Mock = await ethers.getContractAt(
    //             vrfCoordinatorV2MockDeployment.abi,
    //             vrfCoordinatorV2MockDeployment.address,
    //             signer,
    //         )
    //         await vrfCoordinatorV2Mock.fulfillRandomWords(requestId, randomIpfsNft.target)
    //     }
    // })

    // Dynamic SVG NFT
    const highValue = ethers.parseEther("1") // 4000 dollar = high value
    const dynamicSvgNftDeployment = await deployments.get("DynamicSvgNft")
    dynamicSvgNft = await ethers.getContractAt(
        dynamicSvgNftDeployment.abi,
        dynamicSvgNftDeployment.address,
        signer,
    )

    const dynamicSvgNftMintTx = await dynamicSvgNft.mintNft(highValue)
    await dynamicSvgNftMintTx.wait(1)
    console.log(`Dynamic SVG NFT with index 3 has tokenURI: ${await dynamicSvgNft.tokenURI(3)}`)
}

module.exports.tags = ["all", "mint"]

Any help would be greatly appreciated, stuck for days!