[CONFIGURATION-425] FileChangedReloadingStrategy works differently on Unix and Windows

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 1.6
• Fix Version/s: 2.x
• Component/s: File reloading

Environment

Windows 7 x64 and Ubuntu 10.04 Server

• Assignee: Unassigned
• Reporter: Dan Haynes
• Created: 17/Oct/10 22:21
• Updated: 24/Mar/16 20:12

Description

I created a unit test for a configuration class that uses commons configuration. It loads both a set of static properties and a set of dynamic properties, the latter uses FilechangeReloadingStragegy. The unit test copies a file containing an initial set of of dynamic properties (using commons-io FileUtils.copy()) , verifies the values are as expected and then copies an updated set of properties, sleeps longer than the refresh delay and then verifies the new values are in place.

On WIndows it works as expected. It recognizes that FileUtils.copy() has replaced the dynamic.properties file with an updated version and it loads the new property values.

On Linux, nothing I do makes it recognize that the file has been replaced except by actually opening a shell and editing the dynamic.properties values. Then it works as expected.

This may well be my lack of understanding of some Unix filesystem behavior but it seems like FilechangeReloadingStrategy should notice the change to the file one way or the other.

The unit test looks like so:

		final ConfigurationManager cm = new StandardConfigurationManager(staticTestPropertiesFileName, dynamicTestPropertiesFileName);

		/*
		 * Initialize the configuration manager. This should read all the initial values.
		 */
		cm.init();

		Assert.assertEquals(System.getProperty("java.user"), cm.retrieveUserName());

		/*
		 * Verify that the static properties were read.
		 */
		Assert.assertEquals("1.00", cm.retrieveVersionId());

		/*
		 * Verify that the initial values for the dynamic properties were read.
		 */
		Assert.assertEquals(100, cm.retrieveMaxConcurrentLogons());

		if (copyFile(updatedConfigFileName, dynamicTestPropertiesFileName))
		{
			/*
			 * The default update window for Apache commons configuration file reload strategy is 5 seconds
			 * so wait more than 5 seconds to ensure the new value will be read.
			 */			
			log.info("Sleeping until configuration refresh delay has passed");
			sleep(6000L);
			log.info("Woke, resuming test, maxConcurrentLogons = " + cm.retrieveMaxConcurrentLogons());
				
			/*
			 * Verify that the property was updated to the expected new value.
			 */
>>> this fails every time on Linux:	Assert.assertEquals(1, cm.retrieveMaxConcurrentLogons());
		}
		else
		{
			Assert.fail("Couldn't copy updated test properties file");
		}

I've tried everything I could think of to trigger the reload strategy. After calling FileUtils.copy() on the file I added a FileUtils.touch() on the destination file. That didn't work so I added a "Process process = runtime.exec("touch " + destFile.getAbsolutePath());" to be absolutely 100% certain the file timestamp is being updated. It gets updated, but the reloading strategy never recognizes it.

I googled and searched the JIRA incidents and the only thing I can find that looks similar are some references to a problem in V1.1 that was fixed long ago.