Cadence

# Install Cadence Service Locally

To get started with Cadence, you need to set up three components successfully.

  • A Cadence server hosting dependencies that Cadence relies on such as Cassandra, Elastic Search, etc
  • A Cadence domain for you workflow application
  • A Cadence worker service hosting your workflows

# 0. Prerequisite - Install docker

Follow the Docker installation instructions found here: https://docs.docker.com/engine/installation/ (opens new window)

# 1. Run Cadence Server Using Docker Compose

Download the Cadence docker-compose file:


curl -O https://raw.githubusercontent.com/uber/cadence/master/docker/docker-compose.yml && curl -O https://raw.githubusercontent.com/uber/cadence/master/docker/prometheus/prometheus.yml

Then start Cadence Service by running:

docker-compose up

Please keep this process running at background.

# 2. Register a Domain Using the CLI

In a new terminal, create a new domain called test-domain (or choose whatever name you like) by running:

docker run --network=host --rm ubercadence/cli:master --do test-domain domain register -rd 1

Check that the domain is indeed registered:

> docker run --network=host --rm ubercadence/cli:master --do test-domain domain describe
Name: test-domain
Description:
OwnerEmail:
DomainData: map[]
Status: REGISTERED
RetentionInDays: 1
EmitMetrics: false
ActiveClusterName: active
Clusters: active
ArchivalStatus: DISABLED
Bad binaries to reset:
+-----------------+----------+------------+--------+
| BINARY CHECKSUM | OPERATOR | START TIME | REASON |
+-----------------+----------+------------+--------+
+-----------------+----------+------------+--------+
>

Please remember the domains you created because they will be used in your worker implementation and Cadence CLI commands.

# What's Next

So far you've successfully finished two prerequisites to your Cadence application. The next steps are to implement a simple worker service that hosts your workflows and to run your very first hello world Cadence workflow.

Go to Java HelloWorld or Golang HelloWorld.

# Troubleshooting

There can be various reasons that docker-compose up cannot succeed:

  • In case of the image being too old, update the docker image by docker pull ubercadence/server:master-auto-setup and retry
  • In case of the local docker env is messed up: docker system prune --all and retry (see details about it (opens new window) )
  • See logs of different container:
    • If Cassandra is not able to get up: docker logs -f docker_cassandra_1
    • If Cadence is not able to get up: docker logs -f docker_cadence_1
    • If Cadence Web is not able to get up: docker logs -f docker_cadence-web_1

If the above is still not working, open an issue in Server(main) repo (opens new window).

← Java hello world →