User InterfaceHttp proxy
Is nullified
A copy-paste example that checks whether a token value has been nullified through the HTTP proxy.
This example checks if a Y value has been nullified by calling the /is-nullified HTTP proxy endpoint.
Quick start
-
Requirements: Node 18+, a Y value (128-bit) to check, default chain
84532(Base Sepolia). Override the proxy withBUBBLE_PROXY_URLif needed. -
Install dependencies:
npm install soda-bubble-sdk ethers ethereumjs-util
Example script (is_nullified.mjs)
const Y_VALUE = process.env.Y_VALUE; // bigint as decimal or hex (e.g. 0xabc...)
if (!Y_VALUE) throw new Error("Set Y_VALUE env var (hex or decimal)");
const CHAIN_ID = Number(process.env.CHAIN_ID || 84532);
const PROXY_URL = process.env.BUBBLE_PROXY_URL || "https://proxy2.bubble.sodalabs.net";
const parseY = (value) => {
const asString = String(value);
return asString.startsWith("0x") ? BigInt(asString) : BigInt(asString);
};
const yToBase64 = (y) => {
const hex = y.toString(16).padStart(32, "0"); // 16 bytes -> 32 hex chars
const bytes = Buffer.from(hex, "hex");
if (bytes.length !== 16) throw new Error("Y value must be exactly 16 bytes (128-bit)");
return bytes.toString("base64");
};
const main = async () => {
const y = parseY(Y_VALUE);
const yBase64 = yToBase64(y);
const res = await fetch(`${PROXY_URL}/is-nullified`, {
method: "POST",
headers: { "Content-Type": "application/json" },
body: JSON.stringify({
y_value: yBase64,
chain_id: CHAIN_ID,
}),
});
if (!res.ok) throw new Error(await res.text());
const data = await res.json();
console.log("Response:", data);
console.log("Nullified?:", data.response === true);
};
main().catch(err => {
console.error("is-nullified failed:", err);
process.exit(1);
});Run it:
Y_VALUE=0xabc123... CHAIN_ID=84532 node is_nullified.mjsThe script encodes the Y value to 16 bytes (base64), POSTs to /is-nullified, and prints whether it is nullified along with the raw response.***