How do I get the properties of watcher in plugin developing

[WinterWaterWarm]

For example，plugin trace-ignore-plugin registers a traceIgnorePatternWatcher as BootService
apm-sniffer/optional-plugins/trace-ignore-plugin/src/main/resources/META-INF/services/org.apache.skywalking.apm.agent.core.boot.BootService

apm-sniffer/optional-plugins/trace-ignore-plugin/src/main/java/org/apache/skywalking/apm/plugin/trace/ignore/TraceIgnoreExtendService.java


How can I call the method value of watcher at any time in plugin developing?

[wu-sheng]

What your ask doesn't make any sense. You are developing something but don't aware of how it works?

[WinterWaterWarm]

Here's what I want to do:

1. Register a AgentConfigWatcher to collect dynamic configuraions named plugin.http.include_http_headers

import org.apache.skywalking.apm.agent.core.conf.dynamic.AgentConfigChangeWatcher;
import org.apache.skywalking.apm.agent.core.logging.api.ILog;
import org.apache.skywalking.apm.agent.core.logging.api.LogManager;

public class IncludeHttpHeaderWatcher extends AgentConfigChangeWatcher {
    private static final ILog LOGGER = LogManager.getLogger(IncludeHttpHeaderWatcher.class);

    private String includeHttpHeader;

    public IncludeHttpHeaderWatcher(final String propertyKey) {
        super(propertyKey);
        this.includeHttpHeader = getDefaultValue();
    }

    private void activeSetting(String config) {
        if (LOGGER.isDebugEnable()) {
            LOGGER.debug("Updating using new static config: {}", config);
        }

        try {
            this.includeHttpHeader = config;
        } catch (NumberFormatException ex) {
            LOGGER.error(ex, "Cannot load {} from: {}", getPropertyKey(), config);
        }
    }

    @Override
    public void notify(final ConfigChangeEvent value) {
        if (EventType.DELETE.equals(value.getEventType())) {
            activeSetting(getDefaultValue());
        } else {
            activeSetting(value.getNewValue());
        }
    }

    @Override
    public String value() {
        return includeHttpHeader;
    }

    private String getDefaultValue() {
        return "";
    }
}

i registed this watcher in BootService and it works. I can set the dynamic plugin.http.include_http_headers to includeHttpHeader

@Override
    public void boot() {
        INCLUDE_HTTP_HEADER_WATCHER = new IncludeHttpHeaderWatcher("plugin.http.include_http_headers");
        ServiceManager.INSTANCE.findService(ConfigurationDiscoveryService.class)
                .registerAgentConfigChangeWatcher(INCLUDE_HTTP_HEADER_WATCHER);
    }

2. I want to develop a plugin to collect client header according to dynamic configuration plugin.http.include_http_headers.

so, how can i get the watcher.includeHttpHeader in my plugin code?

[WinterWaterWarm]

Is there something i didn't describe clearly，sincerely ask for help @wu-sheng

[wu-sheng]

You are developing your private features, I don't have time to support that.
As a member of community, I am only available to provide limited supports and feedback.

[WinterWaterWarm]

All right~