@arkhamintelligence/sdk/key-pair.ts

Arkham Intelligence TypeScript SDK

import crypto from "crypto";

/**
 * Arkham Exchange KeyPair
 */
export class KeyPair {
  private apiKey?: string | null;
  private secretBytes?: Buffer | null;

  constructor(apiKey?: string | null, apiSecret?: string | null) {
    this.apiKey = apiKey ?? null;
    this.secretBytes = apiSecret ? Buffer.from(apiSecret, "base64") : null;
  }

  signRequest(method: string, path: string, body = ""): Record<string, string> {
    if (!this.apiKey || !this.secretBytes) {
      return {};
    }

    const expires = String(Math.floor((Date.now() / 1000 + 300) * 1_000_000));
    const signatureString = `${this.apiKey}${expires}${method}${path}${body}`;

    const signature = crypto
      .createHmac("sha256", this.secretBytes)
      .update(signatureString, "utf8")
      .digest("base64");

    return {
      "Arkham-Api-Key": this.apiKey,
      "Arkham-Expires": expires,
      "Arkham-Signature": signature,
    };
  }
}