[SERVER] enable DockerFeature

- checks also if required value in db exists

3 files changed, 51 insertions, 8 deletions

diff --git a/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/App.java b/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/App.java
index b63c0fa0..bb48207f 100644
--- a/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/App.java
+++ b/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/App.java
@@ -54,10 +54,6 @@ public class App {
 			Configurator.initialize(new DefaultConfiguration());
 		}
 
-		AppUtil.logHeader(LOGGER, App.NAME, App.class.getPackage().getImplementationVersion());
-		AppUtil.logProperty(LOGGER, "rpc.version", Long.toString(Version.VERSION));
-		AppUtil.logProperty(LOGGER, "server.features", SupportedFeatures.getFeatureString());
-
 		// get Configuration
 		try {
 			LOGGER.info("Loading configuration");
@@ -67,6 +63,10 @@ public class App {
 			System.exit(1);
 		}
 
+		AppUtil.logHeader(LOGGER, App.NAME, App.class.getPackage().getImplementationVersion());
+		AppUtil.logProperty(LOGGER, "rpc.version", Long.toString(Version.VERSION));
+		AppUtil.logProperty(LOGGER, "server.features", SupportedFeatures.getFeatureString());
+
 		// Update database schema if applicable
 		try {
 			Updater.updateDatabase();
diff --git a/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/SupportedFeatures.java b/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/SupportedFeatures.java
index a454fc21..c40037cc 100644
--- a/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/SupportedFeatures.java
+++ b/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/SupportedFeatures.java
@@ -1,5 +1,6 @@
 package org.openslx.bwlp.sat;
 
+import org.openslx.bwlp.sat.database.mappers.DbHelper;
 import org.openslx.sat.thrift.version.Feature;
 
 public class SupportedFeatures {
@@ -13,10 +14,8 @@ public class SupportedFeatures {
 		registerFeature(Feature.SERVER_SIDE_COPY);
 		registerFeature(Feature.LECTURE_FILTER_LDAP);
 		registerFeature(Feature.CONFIGURE_USB);
-		// TODO Docker Container currently not as a release Feature. Needs Update of Database.
-		// Enable Feature by adding ("docker", "Docker") to virtualizer table
-		// and rebuild Server with enabled Feature and replace jar on Sat.
-//		registerFeature(Feature.DOCKER_CONTAINER);
+		// add docker feature, but check datebase if available
+		registerFeatureIf(Feature.DOCKER_CONTAINER);
 	}
 
 	public static String getFeatureString() {
@@ -31,4 +30,16 @@ public class SupportedFeatures {
 		}
 	}
 
+	private static void registerFeatureIf(Feature feature) {
+		switch (feature) {
+			case DOCKER_CONTAINER:
+				if (DbHelper.isDockerContainerAvailable())
+					registerFeature(feature);
+				break;
+
+			default:
+				break;
+		}
+	}
+
 }
diff --git a/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/database/mappers/DbHelper.java b/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/database/mappers/DbHelper.java
new file mode 100644
index 00000000..a7e2a191
--- /dev/null
+++ b/dozentenmodulserver/src/main/java/org/openslx/bwlp/sat/database/mappers/DbHelper.java
@@ -0,0 +1,32 @@
+package org.openslx.bwlp.sat.database.mappers;
+
+import java.sql.ResultSet;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.openslx.bwlp.sat.database.Database;
+import org.openslx.bwlp.sat.database.MysqlConnection;
+import org.openslx.bwlp.sat.database.MysqlStatement;
+
+public class DbHelper {
+
+	private static final Logger LOGGER = LogManager.getLogger(DbHelper.class);
+
+	public static boolean isDockerContainerAvailable(){
+
+		try (MysqlConnection connection = Database.getConnection()) {
+			MysqlStatement stmt = connection.prepareStatement(
+					"SELECT *FROM virtualizer WHERE virtid = \"docker\"");
+			ResultSet rs = stmt.executeQuery();
+
+			if (!rs.isBeforeFirst()) {
+				// no data, do not enable.
+				return false;
+			}
+			return true;
+		} catch (Exception e) {
+			LOGGER.error("Query failed in DbHelper.isDockerContainerAvailable()", e);
+			return false;
+		}
+	}
+}