Vault Integration for CaptchaAI API Key Management

Hardcoded API keys in source code are a security liability. HashiCorp Vault centralizes secret management — your CaptchaAI API key is stored encrypted, retrieved at runtime, and every access is logged. This guide shows how to integrate Vault into your CAPTCHA solving pipeline.

Why Vault for CAPTCHA API Keys

Without Vault	With Vault
API key in `.env` file or code	Key stored encrypted in Vault
Key shared via Slack or email	Access via authenticated API
No access audit trail	Every read logged with identity
Manual key rotation	Automated rotation support
Same key across environments	Per-environment keys with policies

Prerequisites

HashiCorp Vault server (self-hosted or HCP Vault)
Vault CLI or API access
CaptchaAI API key
Python 3.8+ or Node.js 18+

Store the API Key in Vault

# Enable the KV secrets engine (if not already enabled)
vault secrets enable -path=secret kv-v2

# Store the CaptchaAI API key
vault kv put secret/captchaai api_key="YOUR_API_KEY"

# Verify
vault kv get secret/captchaai

Create a Vault Policy

Restrict CAPTCHA workers to read-only access:

# captcha-worker-policy.hcl
path "secret/data/captchaai" {
  capabilities = ["read"]
}

path "secret/metadata/captchaai" {
  capabilities = ["read"]
}

Apply the policy:

vault policy write captcha-worker captcha-worker-policy.hcl

Python Integration

# vault_solver.py
import os
import time
import hvac
import requests

# Connect to Vault
vault_client = hvac.Client(
    url=os.environ.get("VAULT_ADDR", "http://127.0.0.1:8200"),
    token=os.environ.get("VAULT_TOKEN"),
)

def get_api_key():
    """Retrieve CaptchaAI API key from Vault."""
    secret = vault_client.secrets.kv.v2.read_secret_version(
        path="captchaai",
        mount_point="secret",
    )
    return secret["data"]["data"]["api_key"]

class CaptchaSolver:
    """CAPTCHA solver with Vault-managed credentials."""

    def __init__(self):
        self.api_key = get_api_key()
        self.session = requests.Session()
        self._key_fetched_at = time.time()
        self._key_refresh_interval = 3600  # Re-fetch key hourly

    def _refresh_key_if_needed(self):
        """Periodically refresh the key from Vault."""
        if time.time() - self._key_fetched_at > self._key_refresh_interval:
            self.api_key = get_api_key()
            self._key_fetched_at = time.time()

    def solve(self, sitekey, pageurl):
        """Solve reCAPTCHA v2 using Vault-managed key."""
        self._refresh_key_if_needed()

        # Submit
        resp = self.session.get("https://ocr.captchaai.com/in.php", params={
            "key": self.api_key,
            "method": "userrecaptcha",
            "googlekey": sitekey,
            "pageurl": pageurl,
            "json": "1",
        })
        result = resp.json()

        if result.get("status") != 1:
            raise Exception(f"Submit failed: {result.get('request')}")

        task_id = result["request"]
        time.sleep(15)

        for _ in range(25):
            poll = self.session.get("https://ocr.captchaai.com/res.php", params={
                "key": self.api_key,
                "action": "get",
                "id": task_id,
                "json": "1",
            })
            poll_result = poll.json()

            if poll_result.get("status") == 1:
                return poll_result["request"]
            if poll_result.get("request") != "CAPCHA_NOT_READY":
                raise Exception(f"Error: {poll_result.get('request')}")

            time.sleep(5)

        raise Exception("Timeout")

# Usage
solver = CaptchaSolver()
token = solver.solve(
    "6Le-wvkSAAAAAPBMRTvw0Q4Muexq9bi0DJwx_mJ-",
    "https://www.google.com/recaptcha/api2/demo"
)
print(f"Token: {token[:30]}...")

JavaScript Integration

// vault_solver.js
const axios = require('axios');

const VAULT_ADDR = process.env.VAULT_ADDR || 'http://127.0.0.1:8200';
const VAULT_TOKEN = process.env.VAULT_TOKEN;

async function getApiKey() {
  const resp = await axios.get(
    `${VAULT_ADDR}/v1/secret/data/captchaai`,
    { headers: { 'X-Vault-Token': VAULT_TOKEN } }
  );
  return resp.data.data.data.api_key;
}

class CaptchaSolver {
  constructor() {
    this.apiKey = null;
    this.keyFetchedAt = 0;
    this.refreshInterval = 3600000; // 1 hour
  }

  async init() {
    this.apiKey = await getApiKey();
    this.keyFetchedAt = Date.now();
  }

  async refreshKeyIfNeeded() {
    if (Date.now() - this.keyFetchedAt > this.refreshInterval) {
      this.apiKey = await getApiKey();
      this.keyFetchedAt = Date.now();
    }
  }

  async solve(sitekey, pageurl) {
    await this.refreshKeyIfNeeded();

    const submit = await axios.get('https://ocr.captchaai.com/in.php', {
      params: {
        key: this.apiKey, method: 'userrecaptcha',
        googlekey: sitekey, pageurl, json: '1',
      },
    });

    if (submit.data.status !== 1) throw new Error(submit.data.request);
    const taskId = submit.data.request;

    await new Promise(r => setTimeout(r, 15000));

    for (let i = 0; i < 25; i++) {
      const poll = await axios.get('https://ocr.captchaai.com/res.php', {
        params: { key: this.apiKey, action: 'get', id: taskId, json: '1' },
      });

      if (poll.data.status === 1) return poll.data.request;
      if (poll.data.request !== 'CAPCHA_NOT_READY') throw new Error(poll.data.request);
      await new Promise(r => setTimeout(r, 5000));
    }
    throw new Error('Timeout');
  }
}

(async () => {
  const solver = new CaptchaSolver();
  await solver.init();

  const token = await solver.solve(
    '6Le-wvkSAAAAAPBMRTvw0Q4Muexq9bi0DJwx_mJ-',
    'https://www.google.com/recaptcha/api2/demo'
  );
  console.log(`Token: ${token.slice(0, 30)}...`);
})();

Authentication Methods

Vault supports multiple authentication methods for workers:

Method	Best For	Setup
Token	Development, CI/CD	`VAULT_TOKEN` env var
AppRole	Production services	Role ID + Secret ID
Kubernetes	K8s workloads	Service account JWT
AWS IAM	EC2/Lambda workers	Instance role

AppRole Example (Recommended for Production)

# AppRole authentication — no static token needed
vault_client = hvac.Client(url=os.environ["VAULT_ADDR"])
vault_client.auth.approle.login(
    role_id=os.environ["VAULT_ROLE_ID"],
    secret_id=os.environ["VAULT_SECRET_ID"],
)

# Now read the secret
secret = vault_client.secrets.kv.v2.read_secret_version(path="captchaai")
api_key = secret["data"]["data"]["api_key"]

Key Rotation Workflow

Generate new CaptchaAI API key in the CaptchaAI dashboard
Update Vault: vault kv put secret/captchaai api_key="NEW_KEY"
Workers automatically pick up the new key on their next refresh cycle
Revoke the old key in CaptchaAI dashboard after all workers have refreshed

No code changes or deployments required.

Troubleshooting

Issue	Cause	Fix
`403 Forbidden` from Vault	Policy doesn't allow read	Check `captcha-worker-policy.hcl` path
`VAULT_TOKEN` expired	Token TTL exceeded	Use AppRole for auto-renewable tokens
Key not refreshing	Refresh interval too long	Reduce `_key_refresh_interval`
Vault unavailable	Network or server issue	Cache key locally with fallback

FAQ

What happens if Vault is down?

Cache the API key in memory when first retrieved. If Vault is unavailable during a refresh, continue using the cached key and log the failure.

Should I store one key per environment?

Yes. Use separate Vault paths: secret/captchaai/dev, secret/captchaai/staging, secret/captchaai/prod.

Can I use AWS Secrets Manager instead of Vault?

Yes. The pattern is identical — retrieve the secret at runtime from AWS Secrets Manager using boto3. The core principle (no hardcoded keys, rotate without deployments) remains the same.