Add "Search service"

Add basic search features to dev

fda-database-service/services/src/main/java/at/tuwien/config/IndexInitializer.java

+package at.tuwien.config;
+
+import at.tuwien.entities.database.Database;
+import com.google.common.collect.ImmutableMap;
+import lombok.extern.log4j.Log4j2;
+import org.springframework.boot.context.event.ApplicationReadyEvent;
+import org.springframework.context.event.EventListener;
+import org.springframework.data.elasticsearch.core.ElasticsearchOperations;
+import org.springframework.data.elasticsearch.core.mapping.IndexCoordinates;
+import org.springframework.stereotype.Component;
+
+import java.util.HashMap;
+
+@Component
+@Log4j2
+public class IndexInitializer {
+
+    private final ElasticsearchOperations elasticsearchOperations;
+
+    public IndexInitializer(ElasticsearchOperations elasticsearchOperations) {
+        this.elasticsearchOperations = elasticsearchOperations;
+    }
+
+    @EventListener(ApplicationReadyEvent.class)
+    public void initIndex() {
+        log.debug("creating index");
+        IndexCoordinates indexCoordinates = IndexCoordinates.of("databaseindex");
+        if (!elasticsearchOperations.indexOps(indexCoordinates).exists()) {
+            elasticsearchOperations.indexOps(indexCoordinates).create();
+            elasticsearchOperations.indexOps(indexCoordinates).createMapping(Database.class);
+        }
+    }
+}