expiringBlob: create-and-forget blobs using UUIDv7

This tool uses UUIDv7s in blob keys with UNIX timestamps included to keep track of when they expire. Since UUIDv7s are sortable and the blob list endpoint returns results alphabetically, cleanup (checking the blob list and deleting any expired keys) is efficient since any expired keys will be at the front of the results!

Each ID is prefixed with a prefix (default: expireBlob:) and can be suffixed with a label (parameter order depends on the method). Example blob keys:

expiringBlob:01944432-4837-7a99-94e6-e0e162554e21
^Prefix      ^UUIDv7

expiringBlob:01944432-4837-7a99-94e6-e0e162554e21:aaaa
^Prefix      ^UUIDv7                              ^Label

• createKey: generate a key you can use with @std/blob methods
• set or setJSON: generate a blob key and save content to it in one step
• cleanup: delete expired blobs. You can run this manually or periodically with a cron val. If using a custom prefix, make sure to pass it to this method so that the correct blob list is searched.

By default, createKey, set, and setJSON will create keys that expire in an hour, but you can override this by passing the expireAt: Date | number parameter. For convenience, expireIn is provided with methods to create future dates for each of the following:

• expireIn.hours(2)
• expireIn.minutes(5)
• expireIn.seconds(45)
• expireIn.ms(500)

To request data once you've saved it, use @std/blob's get and getJSON as usual with the key provided by set or setJSON!

Create val
import { cleanup, createKey, expireIn, set, setJSON } from "https://esm.town/v/postpostscript/expiringBlob";
import { blob } from "https://esm.town/v/std/blob";

const aaaa = createKey("aaaa"); // equivalent of createKey("aaaa", expireIn.hours(1))
await blob.setJSON(aaaa, {
  x: 1,
});
console.log(aaaa, await blob.getJSON(aaaa));
// expiringBlob:01944432-4837-7a99-94e6-e0e162554e21:aaaa { x: 1 }

console.log(await set("bbbb", "test", expireIn.seconds(1)));
// expiringBlob:019443fb-6106-77f2-ab0c-5142b099c81a:bbbb

console.log(await setJSON("cccc", { x: 1 }, expireIn.seconds(1)));
// expiringBlob:019443fb-6327-733c-9a0b-c8b9ee9faef0:cccc

await cleanup();
// [no logs]

await new Promise((resolve) => setTimeout(resolve, 1000));
await cleanup();
// deleting expired blob: expiringBlob:019443fb-6106-77f2-ab0c-5142b099c81a:bbbb
// deleting expired blob: expiringBlob:019443fb-6327-733c-9a0b-c8b9ee9faef0:cccc

Create a cron val with the following code to periodically delete expired blobs:

Create val
import { cleanup } from "https://esm.town/v/postpostscript/expiringBlob";

export default () => cleanup();

Migrated from folder: ExpiringBlob/expiringBlob