Retry queries

It is useful to retry write queries from your application when you encounter a transient error. From the list of D1_ERRORs, refer to the Recommended action column to determine if a query should be retried.

Example of retrying queries

Consider the following example of a shouldRetry(...) function, taken from the D1 read replication starter template ↗.

You should make sure your retries apply an exponential backoff with jitter strategy for more successful retries. You can use libraries abstracting that already like @cloudflare/actors ↗, or copy the retry logic ↗ in your own code directly.

import { tryWhile } from "@cloudflare/actors";

function queryD1Example(d1: D1Database, sql: string) {
  return await tryWhile(async () => {
    return await d1.prepare(sql).run();
  }, shouldRetry);
}

function shouldRetry(err: unknown, nextAttempt: number) {
  const errMsg = String(err);
  const isRetryableError =
    errMsg.includes("Network connection lost") ||
    errMsg.includes("storage caused object to be reset") ||
    errMsg.includes("reset because its code was updated");
  if (nextAttempt <= 5 && isRetryableError) {
    return true;
  }
  return false;
}