My guess at s3 bucket adapter for bknd

bknd.config.ts

import type { AstroBkndConfig } from "bknd/adapter/astro";
import type { APIContext } from "astro";
import { em, entity, number, text, libsql } from "bknd/data";
import { secureRandomString } from "bknd/utils";
import { StorageS3Adapter, MediaAdapterRegistry, type S3AdapterConfig } from "bknd/media";
import { syncTypes } from "bknd/plugins";
import { registries } from "bknd";
import {
  LIBSQL_DATABASE_TOKEN,
  LIBSQL_DATABASE_URL,
  S3_API_URL,
  S3_ACCESS_KEY,
  S3_SECRET_ACCESS_KEY
} from "astro:env/server";

let registered = false;
export function registerS3MediaAdapter() {
  if (!registered) {
    registries.media.register("s3", StorageS3Adapter);
    registered = true;
  }

  return (config: Partial<S3AdapterConfig> = {}) => {
    const adapter = new StorageS3Adapter({
      url: config.url || "",
      access_key: config.access_key || "",
      secret_access_key: config.secret_access_key || "",
      ...config
    });
    return adapter.toJSON(true);
  };
}

export default {
  // we can use any libsql config, and if omitted, uses in-memory
  app: (ctx: APIContext) => ({
    connection: libsql({
      url: LIBSQL_DATABASE_URL ?? "file:.astro/content.db",
      authToken: LIBSQL_DATABASE_TOKEN
    })
  }),
  // an initial config is only applied if the database is empty
  initialConfig: {
    media: {
      enabled: true,
      adapter: registerS3MediaAdapter()({
        url: S3_API_URL || "",
        access_key: S3_ACCESS_KEY || "",
        secret_access_key: S3_SECRET_ACCESS_KEY || ""
      })
    },
  },
} as const satisfies AstroBkndConfig<APIContext>;