If you want to copy an existing Policy instead of creating a new one by yourself or reference an existing Policy, you can adjust the ModifyThing command like demonstrated in the following examples.
This only works if a Thing with the given thingId
does not exist, yet. If it exists the _copyPolicyFrom
field will be ignored.
If no Thing with ID org.eclipse.ditto:fancy-thing_53
exists, this command will create a new Thing with ID org.eclipse.ditto:fancy-thing_53
with a Policy copied from the Policy with ID org.eclipse.ditto:the_policy_id_to_copy
.
{ "topic": "org.eclipse.ditto/fancy-thing/things/twin/commands/modify", "headers": { "correlation-id": "<command-correlation-id>" }, "path": "/", "value": { "thingId": "org.eclipse.ditto:fancy-thing_53", "policyId": "org.eclipse.ditto:the_policy_id", "_copyPolicyFrom": "com:acme:the_policy_id_to_copy" } }
If no Thing with ID org.eclipse.ditto:fancy-thing_53
exists, this command will create a new Thing with ID org.eclipse.ditto:fancy-thing_53
with a Policy copied from a Thing with ID org.eclipse.ditto:fancy-thing_52
.
{ "topic": "org.eclipse.ditto/fancy-thing/things/twin/commands/modify", "headers": { "correlation-id": "<command-correlation-id>" }, "path": "/", "value": { "thingId": "org.eclipse.ditto:fancy-thing_53", "policyId": "org.eclipse.ditto:the_policy_id", "_copyPolicyFrom": "{% raw %}{{ ref:things/com:acme:fancy-thing_52/policyId }}{% endraw %}" } }