muhtasimtanmoy / cadence

Cadence is a distributed, scalable, durable, and highly available orchestration engine to execute asynchronous long-running business logic in a scalable and resilient way.

Cadence

This repo contains the source code of the Cadence server and other tooling including CLI, schema tools, bench and canary.

You can implement your workflows with one of our client libraries. The Go and Java libraries are officially maintained by the Cadence team, while the Python and Ruby client libraries are developed by the community.

You can also use iWF as a DSL framework on top of Cadence.

See Maxim's talk at Data@Scale Conference for an architectural overview of Cadence.

Visit cadenceworkflow.io to learn more about Cadence. Join us in Cadence Documentation project. Feel free to raise an Issue or Pull Request there.

Community

• Github Discussion
  • Best for Q&A, support/help, general discusion, and annoucement
• StackOverflow
  • Best for Q&A and general discusion
• Github Issues
  • Best for reporting bugs and feature requests
• Slack
  • Best for contributing/development discussion

Getting Started

Start the cadence-server

To run Cadence services locally, we highly recommend that you use Cadence service docker to run the service. You can also follow the instructions to build and run it.

Please visit our documentation site for production/cluster setup.

Run the Samples

Try out the sample recipes for Go or Java to get started.

Use Cadence CLI

Cadence CLI can be used to operate workflows, tasklist, domain and even the clusters.

You can use the following ways to install Cadence CLI:

• Use brew to install CLI: brew install cadence-workflow
  • Follow the instructions if you need to install older versions of CLI via homebrew. Usually this is only needed when you are running a server of a too old version.
• Use docker image for CLI: docker run --rm ubercadence/cli:<releaseVersion> or docker run --rm ubercadence/cli:master . Be sure to update your image when you want to try new features: docker pull ubercadence/cli:master
• Build the CLI binary yourself, check out the repo and run make cadence to build all tools. See CONTRIBUTING for prerequisite of make command.
• Build the CLI image yourself, see instructions

Cadence CLI is a powerful tool. The commands are organized by tabs. E.g. workflow->batch->start, or admin->workflow->describe.

Please read the documentation and always try out --help on any tab to learn & explore.

Use Cadence Web

Try out Cadence Web UI to view your workflows on Cadence. (This is already available at localhost:8088 if you run Cadence with docker compose)

Contributing

We'd love your help in making Cadence great. Please review our contribution guide.

If you'd like to propose a new feature, first join the Slack channel to start a discussion and check if there are existing design discussions. Also peruse our design docs in case a feature has been designed but not yet implemented. Once you're sure the proposal is not covered elsewhere, please follow our proposal instructions.

Other binaries in this repo

Bench/stress test workflow tools

See bench documentation.

Periodical feature health check workflow tools(aka Canary)

See canary documentation.

Schema tools for SQL and Cassandra

The tools are for manual setup or upgrading database schema

• If server runs with Cassandra, Use Cadence Cassandra tool
• If server runs with SQL database, Use Cadence SQL tool

The easiest way to get the schema tool is via homebrew.

brew install cadence-workflow also includes cadence-sql-tool and cadence-cassandra-tool.

• The schema files are located at /usr/local/etc/cadence/schema/.
• To upgrade, make sure you remove the old ElasticSearch schema first: mv /usr/local/etc/cadence/schema/elasticsearch /usr/local/etc/cadence/schema/elasticsearch.old && brew upgrade cadence-workflow. Otherwise ElasticSearch schemas may not be able to get updated.
• Follow the instructions if you need to install older versions of schema tools via homebrew. However, easier way is to use new versions of schema tools with old versions of schemas. All you need is to check out the older version of schemas from this repo. Run git checkout v0.21.3 to get the v0.21.3 schemas in the schema folder.

License

MIT License, please see LICENSE for details.