feat(#406): System / gRPC API should provide information about evitaD…

…B server version

We need to provide sever version in gRPC evitaLab API, so then the clients can visualize it and reason about it. We should also provide a method to detect the client version. Java client should log an error/warning if its minor version differs from the server version, as it might signal compatibility problems.

Implemented system endpoint.

evita_common/src/main/java/io/evitadb/utils/StringUtils.java

@@ -35,6 +35,7 @@
 import java.security.NoSuchAlgorithmException;
 import java.text.Normalizer;
 import java.text.Normalizer.Form;
+import java.time.Duration;
 import java.util.Arrays;
 import java.util.HexFormat;
 import java.util.List;
@@ -527,10 +528,38 @@ public static String replaceEach(final String text, final String[] searchList, f
 		return replaceEach(text, searchList, replacementList, false, 0);
 	}
 
+	/**
+	 * Formats duration to human readable format.
+	 * @param duration duration to be formatted
+	 * @return formatted duration
+	 */
+	@Nonnull
+	public static String formatDuration(@Nonnull Duration duration) {
+		long days = duration.toDaysPart();
+		long hours = duration.toHoursPart();
+		long minutes = duration.toMinutesPart();
+		long seconds = duration.toSecondsPart();
+
+		StringBuilder sb = new StringBuilder(32);
+
+		if (days > 0) {
+			sb.append(days).append("d ");
+		}
+		if (hours > 0 || days > 0) {
+			sb.append(hours).append("h ");
+		}
+		if (minutes > 0 || hours > 0 || days > 0) {
+			sb.append(minutes).append("m ");
+		}
+		sb.append(seconds).append("s");
+
+		return sb.toString().trim();
+	}
+
 	/**
 	 * <p>
 	 * Replace all occurrences of Strings within another String.
-	 * This is a private recursive helper method for {@link #replaceEachRepeatedly(String, String[], String[])} and
+	 * This is a private recursive helper method for {@link #replaceEach(String, String[], String[])} and
 	 * {@link #replaceEach(String, String[], String[])}
 	 * </p>
 	 *

evita_external_api/evita_external_api_system/src/main/java/io/evitadb/externalApi/system/SystemProviderRegistrar.java

@@ -23,6 +23,7 @@
 
 package io.evitadb.externalApi.system;
 
+import io.evitadb.api.requestResponse.system.SystemStatus;
 import io.evitadb.core.Evita;
 import io.evitadb.exception.EvitaInternalError;
 import io.evitadb.externalApi.configuration.ApiOptions;
@@ -33,6 +34,7 @@
 import io.evitadb.externalApi.http.ExternalApiProviderRegistrar;
 import io.evitadb.externalApi.system.configuration.SystemConfig;
 import io.evitadb.utils.CertificateUtils;
+import io.evitadb.utils.StringUtils;
 import io.undertow.Handlers;
 import io.undertow.server.handlers.BlockingHandler;
 import io.undertow.server.handlers.PathHandler;
@@ -45,7 +47,9 @@
 import javax.annotation.Nonnull;
 import java.io.File;
 import java.io.IOException;
+import java.time.format.DateTimeFormatter;
 import java.util.Arrays;
+import java.util.stream.Collectors;
 
 /**
  * Registers System API provider to provide system API to clients.
@@ -54,6 +58,7 @@
  */
 public class SystemProviderRegistrar implements ExternalApiProviderRegistrar<SystemConfig> {
 	private static final String ENDPOINT_SERVER_NAME = "server-name";
+	private static final String ENDPOINT_SYSTEM_STATUS = "status";
 
 	@Nonnull
 	@Override
@@ -99,6 +104,21 @@ public ExternalApiProvider<SystemConfig> register(@Nonnull Evita evita, @Nonnull
 			}
 		);
 
+		router.addExactPath(
+			"/" + ENDPOINT_SYSTEM_STATUS,
+			exchange -> {
+				exchange.setStatusCode(StatusCodes.OK);
+				exchange.getResponseHeaders().put(Headers.CONTENT_TYPE, "application/json");
+				exchange.getResponseSender().send(
+					renderStatus(
+						evita.getConfiguration().name(),
+						evita.getSystemStatus(),
+						apiOptions
+					)
+				);
+			}
+		);
+
 		final ResourceHandler fileSystemHandler;
 		try (ResourceManager resourceManager = new FileResourceManager(file, 100)) {
 			fileSystemHandler = new ResourceHandler(
@@ -152,4 +172,47 @@ public ExternalApiProvider<SystemConfig> register(@Nonnull Evita evita, @Nonnull
 			throw new EvitaInternalError(e.getMessage(), e);
 		}
 	}
+
+	/**
+	 * Renders the status of the evitaDB server as a JSON string.
+	 *
+	 * @param instanceId    the unique identifier of the server instance
+	 * @param systemStatus  the SystemStatus object containing information about the server
+	 * @param apiOptions    the common settings shared among all the API endpoints
+	 * @return the JSON string representing the server status
+	 */
+	@Nonnull
+	private static String renderStatus(@Nonnull String instanceId, @Nonnull SystemStatus systemStatus, ApiOptions apiOptions) {
+		return String.format("""
+			{
+			   "serverName": "%s",
+			   "version": "%s",
+			   "startedAt": "%s",
+			   "uptime": %d,
+			   "uptimeForHuman": "%s",
+			   "catalogsCorrupted": %d,
+			   "catalogsOk": %d,
+			   "apis": [
+			%s
+			   ]
+			}""",
+			instanceId,
+			systemStatus.version(),
+			DateTimeFormatter.ISO_OFFSET_DATE_TIME.format(systemStatus.startedAt()),
+			systemStatus.uptime().toSeconds(),
+			StringUtils.formatDuration(systemStatus.uptime()),
+			systemStatus.catalogsCorrupted(),
+			systemStatus.catalogsOk(),
+			apiOptions.endpoints().entrySet().stream()
+				.map(
+					entry -> "      {\n         \"" + entry.getKey() + "\": [\n" +
+						Arrays.stream(entry.getValue().getBaseUrls(apiOptions.exposedOn()))
+							.map(it -> "            \"" + it + "\"")
+							.collect(Collectors.joining(",\n")) +
+						"\n         ]\n      }"
+				)
+				.collect(Collectors.joining(",\n"))
+		);
+	}
+
 }

evita_functional_tests/src/test/java/io/evitadb/utils/StringUtilsTest.java

@@ -25,6 +25,8 @@
 
 import org.junit.jupiter.api.Test;
 
+import java.time.Duration;
+
 import static io.evitadb.utils.StringUtils.*;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
@@ -208,4 +210,40 @@ void shouldAddRightPadding() {
 		assertEquals("a         ", StringUtils.rightPad("a", " ", 10));
 		assertEquals("dsfadfsadfsadfd", StringUtils.rightPad("dsfadfsadfsadfd", " ", 10));
 	}
+
+	@Test
+	void shouldFormatDurationLessThanADay() {
+		Duration duration = Duration.ofHours(5).plusMinutes(30).plusSeconds(15);
+		String formattedDuration = StringUtils.formatDuration(duration);
+		assertEquals("5h 30m 15s", formattedDuration);
+	}
+
+	@Test
+	void shouldFormatDurationExactlyOneDay() {
+		Duration duration = Duration.ofDays(1);
+		String formattedDuration = StringUtils.formatDuration(duration);
+		assertEquals("1d 0h 0m 0s", formattedDuration);
+	}
+
+	@Test
+	void shouldFormatDurationMoreThanOneDay() {
+		Duration duration = Duration.ofDays(2).plusHours(5).plusMinutes(30).plusSeconds(15);
+		String formattedDuration = StringUtils.formatDuration(duration);
+		assertEquals("2d 5h 30m 15s", formattedDuration);
+	}
+
+	@Test
+	void shouldFormatDurationMinutesOnly() {
+		Duration duration = Duration.ofMinutes(30).plusSeconds(15);
+		String formattedDuration = StringUtils.formatDuration(duration);
+		assertEquals("30m 15s", formattedDuration);
+	}
+
+	@Test
+	void shouldFormatZeroDuration() {
+		Duration duration = Duration.ZERO;
+		String formattedDuration = StringUtils.formatDuration(duration);
+		assertEquals("0s", formattedDuration);
+	}
+
 }