docs/books/modules/user-guide/adding-metadata-to-connections.adoc

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// Module is included in the following assemblies:
//
// configuring-network-connections.adoc

[id='adding-metadata-to-connections-{context}']
= Adding metadata to connections

In a complex topology, it can be useful to add metadata to connections so that messages can be handled programmatically.

.Procedure

include::{FragmentDir}/fragment-router-open-config-file-step.adoc[]

. Add arbitrary JSON to the `connector` configuration using the 'openProperties' attribute.
+
--
This example adds the property `label` with the value `green`.

[options="nowrap",subs="+quotes"]
----
connector {
   name: broker
   role: route-container
   host: 127.0.0.1
   port: 22180
   saslMechanisms: ANONYMOUS
   openProperties: {
      "label": "green"
   }
}
----

Note the following restrictions on the JSON entries:
 
* ASCII characters only for keys
* The following keys are not allowed:
** product
** version
** failover-server-list
** network-host
** port
** scheme
** hostname
** any key starting with `qd.`
** any key starting with `x-opt-qd.`

The `openProperties` attribute can only be set for a connector with a `normal` or `route-container` role. 
You cannot set the attribute for connectors that have the following settings:

* `role: inter-router`
* `role: edge`
* `http: true`

The JSON format supports lists, maps and multiple entries, for example:

----
connector {
   name: broker
   role: route-container
   host: 127.0.0.1
   port: 22180
   saslMechanisms: ANONYMOUS
   openProperties: {
      "foo": "bar",
      "integer": 7,
 "list":  ["a", 1, "b", -9, true],
 "map":  {"key1": null, "key2": [1, 2, 3]},
 }
   cost: 10
}
----
--