[FlowAggregator] Fix live config updates for IPFIXExporter

[antoninbas]

In particular, updates to recordContents.podLabels and recordFormat were ignored, without any kind of warning.

[tnqn]

It seems unsupported changes could return false here and leads to "New IPFIXExporter configuration" log even nothing changes, for example, by updating enable. Could it be confusing?

According to the description "updates to recordContents.podLabels and recordFormat were ignored, without any kind of warning.", should it warn users that it's unsupported?

[antoninbas]

If there is an update to enable, this code will never be executed:

antrea/pkg/flowaggregator/flowaggregator.go

Lines 618 to 634 in 264372d

	if opt.Config.FlowCollector.Enable {
	if fa.ipfixExporter == nil {
	klog.InfoS("Enabling Flow-Collector")
	fa.ipfixExporter = newIPFIXExporter(fa.k8sClient, opt, fa.registry)
	fa.ipfixExporter.Start()
	klog.InfoS("Enabled Flow-Collector")
	} else {
	fa.ipfixExporter.UpdateOptions(opt)
	}
	} else {
	if fa.ipfixExporter != nil {
	klog.InfoS("Disabling Flow-Collector")
	fa.ipfixExporter.Stop()
	fa.ipfixExporter = nil
	klog.InfoS("Disabled Flow-Collector")
	}
	}

All other fields in opt.Config.FlowCollector are now handled correctly with this PR, which is why I used reflect.DeepEqual on the struct. I took a similar approach for the "LogExporter":

antrea/pkg/flowaggregator/exporter/log.go

Lines 150 to 161 in 264372d

	func (e *LogExporter) UpdateOptions(opt *options.Options) {
	config := opt.Config.FlowLogger
	if reflect.DeepEqual(e.config, config) {
	return
	}
	klog.InfoS("Updating FlowLogger")
	e.stop()
	e.config = config
	klog.InfoS("New FlowLogger configuration", "path", config.Path, "maxSize", config.MaxSize, "maxBackups", config.MaxBackups, "maxAge", config.MaxAge, "compress", *config.Compress, "prettyPrint", *config.PrettyPrint)
	e.buildFilters()
	e.start()
	}

One could argue that this code is a bit clumsy. It may not have been a great idea to support live config updates for the Flow Aggregator in the first place...

According to the description "updates to recordContents.podLabels and recordFormat were ignored, without any kind of warning.", should it warn users that it's unsupported?

With this PR, these updates should now be supported.

[tnqn]

Got it, thanks for the explanation.

[tnqn]

LGTM

[yuntanghsu]

LGTM

[antoninbas]

/test-all