Helius Rate Limits

const RETRYABLE = new Set([408, 429, 500, 502, 503, 504]);

export async function callWithRetry<T>(
  request: () => Promise<Response>,
  maxAttempts = 5,
): Promise<T> {
  let delay = 1000;
  for (let attempt = 1; attempt <= maxAttempts; attempt++) {
    const res = await request();
    if (res.ok) return (await res.json()) as T;

    if (!RETRYABLE.has(res.status) || attempt === maxAttempts) {
      throw new Error(`${res.status} after ${attempt} attempt(s): ${await res.text()}`);
    }

    const jitterMs = delay * (0.75 + Math.random() * 0.5);
    await new Promise((r) => setTimeout(r, jitterMs));
    delay = Math.min(delay * 2, 30_000);
  }
  throw new Error("unreachable");
}

import random
import time

RETRYABLE = {408, 429, 500, 502, 503, 504}

def call_with_retry(request, max_attempts: int = 5):
    delay = 1.0
    for attempt in range(1, max_attempts + 1):
        response = request()
        if response.ok:
            return response.json()

        if response.status_code not in RETRYABLE or attempt == max_attempts:
            response.raise_for_status()

        time.sleep(delay * random.uniform(0.75, 1.25))
        delay = min(delay * 2, 30.0)

call_with_retry() {
  local attempt=1 delay=1 body status
  while [ "$attempt" -le 5 ]; do
    response=$(curl -sS -w "\n%{http_code}" "$@")
    body=$(printf '%s\n' "$response" | sed '$d')
    status=$(printf '%s\n' "$response" | tail -n1)
    case "$status" in
      2*) printf '%s\n' "$body"; return 0 ;;
      408|429|500|502|503|504) ;;  # fall through and retry
      *) printf '%s\n' "$body" >&2; return 1 ;;
    esac
    # ~delay seconds with 25% jitter
    sleep "$(awk -v d="$delay" 'BEGIN { srand(); print d * (0.75 + rand() * 0.5) }')"
    delay=$(( delay * 2 > 30 ? 30 : delay * 2 ))
    attempt=$(( attempt + 1 ))
  done
  return 1
}