Expire Git refresh rate when the monitor endpoint is notified

spring-cloud-config-monitor/src/main/java/org/springframework/cloud/config/monitor/EnvironmentMonitorAutoConfiguration.java

@@ -18,6 +18,7 @@
 
 import java.util.List;
 
+import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
@@ -30,6 +31,7 @@
 import org.springframework.boot.web.servlet.FilterRegistrationBean;
 import org.springframework.cloud.bus.BusProperties;
 import org.springframework.cloud.client.discovery.DiscoveryClient;
+import org.springframework.cloud.config.server.environment.JGitEnvironmentRepository;
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -115,11 +117,12 @@ protected static class PropertyPathEndpointConfiguration {
 
 		@Bean
 		public PropertyPathEndpoint propertyPathEndpoint(List<PropertyPathNotifier> notifiers,
-				MonitorConfigurationProperties monitorProperties) {
+				MonitorConfigurationProperties monitorProperties,
+				ObjectProvider<JGitEnvironmentRepository> gitRepositories) {
 			Assert.state(!notifiers.isEmpty(), "At least one PropertyPathNotifier must be available");
 			return new PropertyPathEndpoint(new CompositePropertyPathNotificationExtractor(this.extractors), notifiers,
 					monitorProperties.getMaxDashes(), monitorProperties.getMaxPaths(),
-					monitorProperties.getIgnoredPaths());
+					monitorProperties.getIgnoredPaths(), gitRepositories.orderedStream().toList());
 		}
 
 	}

spring-cloud-config-monitor/src/main/java/org/springframework/cloud/config/monitor/PropertyPathEndpoint.java

@@ -27,6 +27,7 @@
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
+import org.springframework.cloud.config.server.environment.JGitEnvironmentRepository;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.MediaType;
 import org.springframework.util.StringUtils;
@@ -71,6 +72,13 @@ public class PropertyPathEndpoint {
 
 	private final List<Pattern> ignoredPaths;
 
+	/**
+	 * Git repositories of this config server. Their refresh rate is expired before the
+	 * applications are notified, so that the configuration the applications fetch on
+	 * refresh includes the change that triggered the notification.
+	 */
+	private final List<JGitEnvironmentRepository> gitRepositories;
+
 	public PropertyPathEndpoint(PropertyPathNotificationExtractor extractor, PropertyPathNotifier notifier) {
 		this(extractor, List.of(notifier), MonitorConfigurationProperties.DEFAULT_MAX_DASHES);
 	}
@@ -88,7 +96,13 @@ public PropertyPathEndpoint(PropertyPathNotificationExtractor extractor, List<Pr
 
 	public PropertyPathEndpoint(PropertyPathNotificationExtractor extractor, List<PropertyPathNotifier> notifiers,
 			int maxDashes, int maxPaths, List<String> ignoredPaths) {
+		this(extractor, notifiers, maxDashes, maxPaths, ignoredPaths, Collections.emptyList());
+	}
+
+	public PropertyPathEndpoint(PropertyPathNotificationExtractor extractor, List<PropertyPathNotifier> notifiers,
+			int maxDashes, int maxPaths, List<String> ignoredPaths, List<JGitEnvironmentRepository> gitRepositories) {
 		this.extractor = extractor;
+		this.gitRepositories = gitRepositories == null ? Collections.emptyList() : gitRepositories;
 		this.notifiers = notifiers;
 		this.maxDashes = maxDashes;
 		this.maxPaths = maxPaths;
@@ -121,6 +135,9 @@ public Set<String> notifyByPath(@RequestHeader HttpHeaders headers, @RequestBody
 				for (String service : services) {
 					log.info("Refresh for: " + service);
 				}
+				for (JGitEnvironmentRepository repository : this.gitRepositories) {
+					repository.expireRefreshRate();
+				}
 				for (PropertyPathNotifier notifier : this.notifiers) {
 					notifier.notifyApplications(services);
 				}

spring-cloud-config-monitor/src/test/java/org/springframework/cloud/config/monitor/PropertyPathEndpointTests.java

@@ -22,8 +22,12 @@
 import java.util.List;
 import java.util.Set;
 
+import io.micrometer.observation.ObservationRegistry;
 import org.junit.jupiter.api.Test;
 
+import org.springframework.cloud.config.server.environment.JGitEnvironmentProperties;
+import org.springframework.cloud.config.server.environment.JGitEnvironmentRepository;
+import org.springframework.core.env.StandardEnvironment;
 import org.springframework.http.HttpHeaders;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -63,6 +67,37 @@ public void testNotifiesAffectedServices() {
 		assertThat(notifiedServices).containsExactly("foo");
 	}
 
+	@Test
+	public void testExpiresGitRefreshRateBeforeNotifyingServices() {
+		JGitEnvironmentRepository repository = gitRepository();
+		repository.setLastRefresh(System.currentTimeMillis());
+		List<Long> lastRefreshWhenNotified = new ArrayList<>();
+		PropertyPathNotifier notifier = services -> lastRefreshWhenNotified.add(repository.getLastRefresh());
+		PropertyPathEndpoint endpoint = new PropertyPathEndpoint(
+				new CompositePropertyPathNotificationExtractor(Collections.emptyList()), List.of(notifier),
+				MonitorConfigurationProperties.DEFAULT_MAX_DASHES, MonitorConfigurationProperties.DEFAULT_MAX_PATHS,
+				Collections.emptyList(), List.of(repository));
+
+		endpoint.notifyByPath(new HttpHeaders(), Collections.singletonMap("path", "foo.yml"));
+
+		assertThat(lastRefreshWhenNotified).containsExactly(0L);
+	}
+
+	@Test
+	public void testDoesNotExpireGitRefreshRateWhenNoServiceIsAffected() {
+		JGitEnvironmentRepository repository = gitRepository();
+		long lastRefresh = System.currentTimeMillis();
+		repository.setLastRefresh(lastRefresh);
+		PropertyPathEndpoint endpoint = new PropertyPathEndpoint(
+				new CompositePropertyPathNotificationExtractor(Collections.emptyList()), List.of(services -> {
+				}), MonitorConfigurationProperties.DEFAULT_MAX_DASHES, MonitorConfigurationProperties.DEFAULT_MAX_PATHS,
+				List.of("foo\\.yml"), List.of(repository));
+
+		endpoint.notifyByPath(new HttpHeaders(), Collections.singletonMap("path", "foo.yml"));
+
+		assertThat(repository.getLastRefresh()).isEqualTo(lastRefresh);
+	}
+
 	@Test
 	public void testNotifyAll() {
 		assertThat(this.endpoint.notifyByPath(new HttpHeaders(), Collections.singletonMap("path", "application.yml"))
@@ -145,4 +180,10 @@ public void testNotifyLimitsPaths() {
 		assertThat(limitedEndpoint.notifyByForm(new HttpHeaders(), request).toString()).isEqualTo("[foo, bar]");
 	}
 
+	private static JGitEnvironmentRepository gitRepository() {
+		JGitEnvironmentProperties properties = new JGitEnvironmentProperties();
+		properties.setRefreshRate(60);
+		return new JGitEnvironmentRepository(new StandardEnvironment(), properties, ObservationRegistry.NOOP);
+	}
+
 }

spring-cloud-config-server/src/main/java/org/springframework/cloud/config/server/environment/JGitEnvironmentRepository.java

@@ -907,6 +907,15 @@ public void setLastRefresh(long lastRefresh) {
 		this.lastRefresh = lastRefresh;
 	}
 
+	/**
+	 * Makes the next request fetch from the remote repository, even if the
+	 * {@link #getRefreshRate() refresh rate} has not elapsed since the last fetch. Has no
+	 * effect if the refresh rate is negative, in which case the remote is never fetched.
+	 */
+	public void expireRefreshRate() {
+		this.lastRefresh = 0;
+	}
+
 	/**
 	 * Wraps the static method calls to {@link org.eclipse.jgit.api.Git} and
 	 * {@link org.eclipse.jgit.api.CloneCommand} allowing for easier unit testing.

spring-cloud-config-server/src/main/java/org/springframework/cloud/config/server/environment/MultipleJGitEnvironmentRepository.java

@@ -119,6 +119,13 @@ public void setRepos(Map<String, PatternMatchingJGitEnvironmentRepository> repos
 		this.repos.putAll(repos);
 	}
 
+	@Override
+	public void expireRefreshRate() {
+		super.expireRefreshRate();
+		this.repos.values().forEach(JGitEnvironmentRepository::expireRefreshRate);
+		new ArrayList<>(this.placeholders.values()).forEach(JGitEnvironmentRepository::expireRefreshRate);
+	}
+
 	@Override
 	public Locations getLocations(String application, String profile, String label) {
 		for (PatternMatchingJGitEnvironmentRepository repository : this.repos.values()) {

spring-cloud-config-server/src/test/java/org/springframework/cloud/config/server/environment/JGitEnvironmentRepositoryIntegrationTests.java

@@ -496,6 +496,37 @@ public void testNewCommitID() throws Exception {
 		assertThat("bar").isEqualTo(fooProperty);
 	}
 
+	@Test
+	public void expireRefreshRateFetchesNewCommitWithinRefreshRate() throws Exception {
+		JGitConfigServerTestData testData = JGitConfigServerTestData
+			.prepareClonedGitRepository(TestConfiguration.class);
+		JGitEnvironmentRepository repository = testData.getRepository();
+		repository.setRefreshRate(60);
+
+		// the first request fetches and starts the refresh rate window
+		Environment environment = repository.findOne("bar", "staging", "master");
+		String startingRemoteVersion = getCommitID(testData.getServerGit().getGit(), "master");
+		assertThat(environment.getVersion()).isEqualTo(startingRemoteVersion);
+
+		// update the remote repo
+		FileOutputStream out = new FileOutputStream(
+				new File(testData.getServerGit().getGitWorkingDirectory(), "bar.properties"));
+		StreamUtils.copy("foo: barNewCommit", Charset.defaultCharset(), out);
+		testData.getServerGit().getGit().add().addFilepattern("bar.properties").call();
+		testData.getServerGit().getGit().commit().setMessage("Updated for pull").call();
+		String updatedRemoteVersion = getCommitID(testData.getServerGit().getGit(), "master");
+
+		// within the refresh rate window the new commit is not fetched
+		environment = repository.findOne("bar", "staging", "master");
+		assertThat(environment.getVersion()).isEqualTo(startingRemoteVersion);
+
+		repository.expireRefreshRate();
+
+		environment = repository.findOne("bar", "staging", "master");
+		assertThat(environment.getVersion()).isEqualTo(updatedRemoteVersion);
+		assertThat(ConfigServerTestUtils.getProperty(environment, "bar.properties", "foo")).isEqualTo("barNewCommit");
+	}
+
 	@Test
 	/**
 	 * In this scenario there is set the refresh rate so the remote repository is not

spring-cloud-config-server/src/test/java/org/springframework/cloud/config/server/environment/MultipleJGitEnvironmentRepositoryTests.java

@@ -88,6 +88,19 @@ private PatternMatchingJGitEnvironmentRepository createRepository(String name, S
 		return repo;
 	}
 
+	@Test
+	public void expireRefreshRateExpiresAllRepositories() {
+		long now = System.currentTimeMillis();
+		this.repository.setLastRefresh(now);
+		this.repository.getRepos().values().forEach(repo -> repo.setLastRefresh(now));
+
+		this.repository.expireRefreshRate();
+
+		assertThat(this.repository.getLastRefresh()).isZero();
+		assertThat(this.repository.getRepos()).isNotEmpty();
+		assertThat(this.repository.getRepos().values()).allSatisfy(repo -> assertThat(repo.getLastRefresh()).isZero());
+	}
+
 	@Test
 	public void defaultRepo() {
 		Environment environment = this.repository.findOne("bar", "staging", "master");