ZDM Demo Client

To get started download this repository. Choose a location to download the project and run the following

git clone https://github.com/alicel/zdm-demo-client

For the migration, you will need two clusters: Origin and Target. You will also need to deploy the ZDM proxy (see the enablement material for all details and commands).

Schema creation

The application uses a simple table with a key/value structure. This table must exist on Origin and Target.

The default name of the keyspace is zdm_demo, but you can specify a different keyspace name if you wish.

Create a keyspace with the chosen name on Origin and Target. Typically this is done through CQL, specifying the desired replication strategy.

For example:

CREATE KEYSPACE IF NOT EXISTS <your_keyspace_name> WITH replication = {'class': 'SimpleStrategy', 'replication_factor': '1' };

If using Astra, create a keyspace with the same name through the Astra UI.

Then, create the following table:

CREATE TABLE <your_keyspace_name>.app_data (
    app_key int PRIMARY KEY,
    app_value text
)

Building and running the application

This application must be deployed to an instance in the Origin infrastructure that can reach the ZDM proxy and the Origin cluster.

Modify the constructor of the SampleDao.java class with credentials and connection parameters valid for your Origin cluster, Target cluster and Proxy instances, changing the code in each switch case as appropriate.

To build this application, run:

mvn clean install

(This has been tested with JDK versions 8, 12 and 14)

The application will connect to Origin, Proxy or Target based on the value of the connectionMode property specified in the run command. Accepted values for this property are ORIGIN, PROXY and TARGET.

To start the web server, run the following command setting connectionMode as appropriate (please note that this property is mandatory). If your keyspace is not called zdm_demo, you will also need to specify the property keyspaceName:

mvn jetty:run -DkeyspaceName=<your_keyspace_name> -DconnectionMode=X

The web server listens on port 8080.

Calling the application REST endpoints

To insert new rows, run:

curl -d 'startkey=5' -d 'numrows=20' -X POST http://localhost:8080/zdm-demo-client/rest/newrows

The command above will insert 20 new rows with sequential keys, starting with key 5 (included). If a starting key is not specified, it defaults to 0. If the number of rows to be inserted is not passed, it defaults to 10.

The row value will include a randomly selected name and city, and the value of this row's key: an example row would have key 15 and value I am Stella in Ottawa from row 15

To retrieve the value of a row (for example row 12) run:

curl -G -d 'rowkey=12' http://localhost:8080/zdm-demo-client/rest/row