Feat(TS): experimental middleware

[grutt]

Description

It is often desirable to perform transformations to the input or output of a task or all task on a client.

For example:

1. payload thinning
2. encryption
3. enrichment with no-serializable data

This experimental feature exposes a middleware concept that is applied to the inputs and outputs at runtime and on run method bindings.

It is available on the 1.2.0-alpha tag.

Type of change

• New feature (non-breaking change which adds functionality)

Example usage:

/* eslint-disable max-classes-per-file */
/* eslint-disable max-classes-per-file */
import { JsonObject } from '@hatchet/v1/types';
import { Serializable, Middleware } from '@hatchet/v1/next';
import { HatchetClient } from '../../client/client';

class EncodeSerializer implements Serializable<unknown> {
  deserialize(input: JsonObject) {
    console.log('client-encode-deserialize', input);

    if (input.encoded && typeof input.encoded === 'string') {
      console.warn('WARNING THIS IS NOT REAL ENCRYPTION');
      const decoded = Buffer.from(input.encoded, 'base64').toString('utf-8');
      return JSON.parse(decoded);
    }

    return input;
  }

  serialize(input: unknown) {
    console.warn('WARNING THIS IS NOT REAL ENCRYPTION');
    const encoded = Buffer.from(JSON.stringify(input)).toString('base64');
    console.log('client-encode-serialize', input);
    return {
      encoded,
    };
  }
}

class EncodeMiddleware implements Middleware {
  input = new EncodeSerializer();
  output = new EncodeSerializer();
}

export const hatchet = HatchetClient.init({
  middleware: [new EncodeMiddleware()],
});

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[Copilot]

Copilot reviewed 12 out of 13 changed files in this pull request and generated no comments.

Files not reviewed (1)

• sdks/typescript/package.json: Language not supported

Comments suppressed due to low confidence (2)

sdks/typescript/src/v1/next/middleware/middleware.ts:38

• The function getDeserializeChain is used for both input and output middleware chains but only maps over m.input.deserialize. For output processing it should map over m.output.deserialize. Consider splitting this into separate functions for input and output.

const getDeserializeChain = (middleware: Middleware[]) => { return middleware.map((m) => m.input.deserialize); }

sdks/typescript/src/v1/next/middleware/middleware.ts:43

• The function getSerializeChain is used for composing the output serialization chain but currently maps over m.input.serialize. It should instead map over m.output.serialize to correctly process output data.

const getSerializeChain = (middleware: Middleware[]) => { return middleware.map((m) => m.input.serialize); }