@temporalio/common

Part of Temporal's TypeScript SDK (see docs and samples).

Common library for code that's used across the Client, Worker, and/or Workflow:

• DataConverter docs
• Failure docs
• API reference

Payload Caching

Experimental. Clients and Workers can cache External Storage payloads, so a payload already in the cache is not retrieved from its storage driver again. Caching is off by default. The SDK exposes a generic PayloadCache interface and an in-memory implementation, InMemoryPayloadCache, exported from @temporalio/client and @temporalio/worker. Pass a payload cache to clients and workers to enable caching, or pass the same cache to both to share it:

import { Client, InMemoryPayloadCache } from '@temporalio/client';
import { Worker } from '@temporalio/worker';

const payloadCache = new InMemoryPayloadCache({
  maxTotalBytes: 128 * 1024 * 1024,
  maxEntries: 20_000,
});

const client = new Client({ payloadCache });
const worker = await Worker.create({ taskQueue, workflowsPath, payloadCache });

n.b. The cache is a best-effort optimization.

External Storage

External Storage caches the final encoded Payload given to a storage driver. Cache hits do not call the storage driver. The reference payload claim data is used to construct the cache key through the following steps:

1. UTF-8 encode the driver name and every claim key and value without normalization.
2. Sort claim keys by unsigned lexicographic order of their UTF-8 bytes.
3. Encode each string as its ASCII base-10 UTF-8 byte length, :, then the original string.
4. Prefix the key with v0/temporal/extstore/.
5. Concatenate the encoded driver name, then each sorted claim key and value.

For driver aws-s3 and claim data { bucket: "abc", key: "1" }, the key is:

v0/temporal/extstore/6:aws-s36:bucket3:abc3:key1:1