[ARIES-1578] blueprint-cm doesn't support org.osgi.service.cm.ConfigurationPlugin

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: blueprint-cm-1.0.9
• Component/s: Blueprint
• Assignee: Guillaume Nodet
• Reporter: Paolo Antinori
• Created: 21/Jun/16 12:48
• Updated: 19/Dec/19 17:36
• Resolved: 05/Sep/16 12:21

Description

I have found an issue with the blueprint-cm module:

it doesn't integrate with possible implementation of org.osgi.service.cm.ConfigurationPlugin registered in the OSGi framework.

That interface allows to intercept ConfigAdmin properties updates, allowing to manipulate their content without persisting them anywhere.

A sample usacase can be a decrypt component that decrypts values on the fly.

The issue on blueprint-cm is with the current implementation of CmPropertyPlaceholder:

https://github.com/apache/aries/blob/trunk/blueprint/blueprint-cm/src/main/java/org/apache/aries/blueprint/compendium/cm/CmPropertyPlaceholder.java#L130-L140

public void updated(Dictionary props) {
    if ("reload".equalsIgnoreCase(updateStrategy) && !equals(properties, props)) {
        LOGGER.debug("Configuration updated for pid={}", persistentId);
        // Run in a separate thread to avoid re-entrance
        new Thread() {
            public void run() {
                blueprintContainer.reload();
            }
        }.start();
    }

updated() is correctly forwarded the props param, containing eventual manipulation of registered ConfigurationPlugin instances, but that content is discarded. The event will trigger a reload of the whole blueprint context, that will fetch the configuration from ConfigAdmin directly, thus bypassing the plugin behavior.

Issue Links

• is related to: ARIES-1732 blueprint-cm - race condition
• links to: GitHub Pull Request #49