Spring command line JSON config containing array - spring

Question

I am using Grails 3 Elasticsearch plugin with Springs external JSON configuration by setting spring.application.json as system property.
The properties are available in the application but I can't find a way to initialize an array properly.
What I am trying to accomplish is to override the default values of the hosts property specified in my application.yml:
environments:
development:
elasticSearch:
client:
hosts:
- {host: "myhost.com", port: 9300}
- {host: "anotherhost.com", port: 9300}
I am setting the property from the command line as follows:
-Dspring.application.json={"environments":{"development":{"elasticSearch":{"client":{"hosts":[{"host":"override1.com", "port":9000},{"host":"override2.com", "port":9100}]}}}}}
I would expect environments.development.elasticSearch.client.hosts to contain an array like it does when initialized from the application.yml, but in fact environments.development.elasticSearch.client containes host[0] and host[1], where each contains the host and the port. The host array from the yml file is still there.
How can I achieve the same behavior using the command line as with the application.yml file?

Answer 1

I believe you can do this the same way that you would if it was set in a .properties file, using a list:
-Denvironments.developmet.elasticSearch.client.hosts={"host":"override1.com", "port":9000},{"host":"override2.com", "port":9100}
and I believe you can also do it as an environment variable...
set ENVIRONMENTS_DEVELOPMENT_ELASTICSEARCH_CLIENT_HOSTS='{"host":"override1.com", "port":9000},{"host":"override2.com", "port":9100}'
There may need to be some quotes around parts of these depending on the shell you are in, the OS, etc.