Add JsonbSetColumnMapperFactory

dc-commons-jdbi/CHANGELOG.md

@@ -6,6 +6,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 ## [Unreleased]
 
+### Added
+
+- `JsonbSetColumnMapperFactory` for JSONB columns that contain a set (just an array in JSON though)
+
 ## [7.0.3](https://github.com/dbmdz/digitalcollections-commons/releases/tag/dc-commons-jdbi-7.0.3) - 2023-09-15
 
 ### Changed

dc-commons-jdbi/src/main/java/de/digitalcollections/commons/jdbi/JsonbSetColumnMapperFactory.java

@@ -0,0 +1,61 @@
+package de.digitalcollections.commons.jdbi;
+
+import com.fasterxml.jackson.databind.JavaType;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import java.io.IOException;
+import java.lang.reflect.ParameterizedType;
+import java.lang.reflect.Type;
+import java.util.Optional;
+import java.util.Set;
+import org.jdbi.v3.core.config.ConfigRegistry;
+import org.jdbi.v3.core.mapper.ColumnMapper;
+import org.jdbi.v3.core.mapper.ColumnMapperFactory;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class JsonbSetColumnMapperFactory<T> implements ColumnMapperFactory {
+
+  private static final Logger LOGGER = LoggerFactory.getLogger(JsonbSetColumnMapperFactory.class);
+
+  private final Class clz;
+  private final ObjectMapper objectMapper;
+
+  public JsonbSetColumnMapperFactory(Class<T> clz, ObjectMapper objectMapper) {
+    this.clz = clz;
+    this.objectMapper = objectMapper;
+  }
+
+  @Override
+  @SuppressWarnings("unchecked")
+  public Optional<ColumnMapper<?>> build(Type type, ConfigRegistry config) {
+    if (!(type instanceof ParameterizedType)) {
+      return Optional.empty();
+    }
+
+    Type listType = ((ParameterizedType) type).getActualTypeArguments()[0];
+    if (!clz.equals(listType)) {
+      return Optional.empty();
+    }
+    return Optional.of(
+        (r, i, c) -> {
+          String jsonb = r.getString(i);
+          if (jsonb == null) {
+            return null;
+          }
+          /* see https://stackoverflow.com/a/11681540 */
+          try {
+            JavaType javaType =
+                objectMapper.getTypeFactory().constructParametricType(Set.class, (Class) listType);
+
+            return objectMapper.readValue(jsonb, javaType);
+          } catch (IOException ex) {
+            ex.printStackTrace();
+            LOGGER.error("Error deserializing JSON", ex);
+            return null;
+          } catch (Exception e) {
+            e.printStackTrace();
+            return null;
+          }
+        });
+  }
+}