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Sending Queries with a NodeJS Script

Developers that don't need a UI for their Axiom on-chain app may want to send queries via a Node.js script. Following the information on this page requires that you previously selected the Script choice from npx create-axiom-app.

We give a tutorial here on how to send a query from Node.js. See SDK Reference for the full reference.

Getting started​

Once you've generated the Script scaffold of the Axiom app, you can find the script located in app/index.ts. The main interface for a Node.js script is the Axiom class exported from @axiom-crypto/client. The class is instantiated via the following constructor, and then initialized.

const axiom = new Axiom({
    circuit: circuit,
    compiledCircuit: compiledCircuit,
    chainId: "11155111",  // Sepolia
    provider: process.env.PROVIDER_URI_SEPOLIA as string,
    privateKey: process.env.PRIVATE_KEY_SEPOLIA as string,
    callback: {
        target: "0x4A4e2D8f3fBb3525aD61db7Fc843c9bf097c362e",
    },
});
await axiom.init();

The Axiom configuration parameters are explained here:

  • circuit: the exported circuit function from your circuit file (here, it's app/axiom/average.circuit.ts)
  • compiledCircuit: the compiled circuit json file from the npx axiom circuit compile command
  • chainId: the chain ID that the circuit will read its on-chain data from
  • provider: a node provider (such as Quicknode, Alchemy, Infura); should be hidden and specified in the .env file
  • privateKey: your test account's private key; should be hidden and specified in the .env file
  • callback: callback data
    • target: address of the smart contract that will receive the callback (your contract)
    • extraData: (optional) additional data to send (data size must be a multiple of 32 bytes)

Proving​

After initialization, you are now ready to generate a compute proof of your circuit. You can now call axiom.prove with some inputs as a json file (or a javascript object).

import inputs from './axiom/data/inputs.json';
...
await axiom.prove(inputs);

Sending the Query​

The output of axiom.prove is arguments that will be passed into axiom.sendQuery to actually send the query on-chain.

const receipt = await axiom.sendQuery();

Sending the Query with IPFS​

Another option for sending a query also involves an on-chain transaction, but the query data is provided by pinning that data to IPFS. We currently provide support for Pinata and Quicknode, with wider support planned in the near future.

info

If you have a specific service that you'd like to have support for, you can also open an issue or a PR in our axiom-tools repository.

The flow for sending a query with IPFS is essentially the same, with a few minor differences. You will need to update the Axiom initialization object to include an ipfsClient and then eventually call sendQueryWithIpfs. An example is provided below:

import { PinataIpfsClient, QuicknodeIpfsClient } from "@axiom-crypto/tools";

// Use either Pinata or Quicknode
const ipfsClient = new PinataIpfsClient(process.env.PINATA_JWT); 
// const ipfsClient = new QuicknodeIpfsClient(process.env.QUICKNODE_API_KEY, process.env.QUICKNODE_GATEWAY);

const axiom = new Axiom({
    circuit: circuit,
    compiledCircuit: compiledCircuit,
    chainId: "11155111",  // Sepolia
    provider: process.env.PROVIDER_URI_SEPOLIA as string,
    privateKey: process.env.PRIVATE_KEY_SEPOLIA as string,
    callback: {
        target: "0x4A4e2D8f3fBb3525aD61db7Fc843c9bf097c362e",
    },
    // Additional `ipfsClient` field
    options: {
        ipfsClient: ipfsClient,
    },
});
await axiom.init();
await axiom.prove(inputs);

// Use `sendQueryWithIpfs`
const receipt = await axiom.sendQueryWithIpfs();

Viewing the status of a Query​

You can view the status of your query by going to Axiom Explorer. You can find your specific query by checking your query's queryId via args.queryId.

Using Different Chains​

We currently support Ethereum Mainnet and Sepolia. You can simply modify the chainId and provider fields to the appropriate values for the chain you want to use. Ensure that the privateKey that you pass in is also funded on the chain that you are using and that the callback target is a valid contract that will accept an Axiom callback. For example, if you want to use Sepolia:

const axiom = new Axiom({
    circuit: circuit,
    compiledCircuit: compiledCircuit,
    chainId: "11155111",  // Sepolia
    provider: process.env.PROVIDER_URI_SEPOLIA as string,
    privateKey: process.env.PRIVATE_KEY_SEPOLIA as string,
    callback: {
        target: "0x81908149E769236F1c9e62b468d07899CB95890F",
    },
});