Compression DataConverter Sample

A custom Cadence DataConverter that JSON-encodes workflow data and then gzip-compresses the bytes. For repetitive JSON payloads this typically achieves 60-80% size reduction, lowering storage cost and bandwidth without changing any workflow or activity code. The decode path caps decompressed payloads (default 10 MB) so a malformed input cannot drive unbounded memory growth.

• Task list: data-compression
• Workflow type: CompressedDataConverterWorkflow

Prerequisites

1. Cadence server running (e.g. Docker Compose from the Cadence repo).
2. From the repo root, build: ./gradlew build.

Register the domain (required once per cluster)

./gradlew -q execute -PmainClass=com.uber.cadence.samples.common.RegisterDomain

Or with the Cadence CLI:

cadence --domain samples-domain domain register

Run the worker (terminal 1)

The worker prints a compression statistics banner showing the before/after sizes of the sample payload, then begins polling the data-compression task list:

./gradlew -q execute -PmainClass=com.uber.cadence.samples.compression.CompressionWorker

Start a workflow (terminal 2)

./gradlew -q execute -PmainClass=com.uber.cadence.samples.compression.CompressionStarter

Or from the Cadence CLI:

cadence --domain samples-domain \
  workflow start \
  --workflow_type CompressedDataConverterWorkflow \
  --tl data-compression \
  --et 60

How it works

• toData: JSON-encode the arguments with the standard JsonDataConverter, then write the bytes through java.util.zip.GZIPOutputStream.
• fromData / fromDataArray: decompress through GZIPInputStream with a configurable max output cap, then delegate to the standard JsonDataConverter.

Source layout

File	Purpose
CompressedJsonDataConverter.java	The custom DataConverter
CompressedDataConverterWorkflow.java	Workflow + activity + sample LargePayload POJOs and generator
CompressionWorker.java	Worker main; wires the converter into WorkflowClientOptions and prints the stats banner
CompressionStarter.java	Thin async starter