Update for s3 tables, to allow setting content-type in aws when inserting records (files) based on file name, hard-coded value, or another field.

this involved adding table & record params to writeFile method - a @Deprecated wrapper w/o those args is provided for backward compatibility

qqq-backend-module-filesystem/src/main/java/com/kingsrook/qqq/backend/module/filesystem/base/actions/AbstractBaseFilesystemAction.java

@@ -124,10 +124,19 @@ public abstract class AbstractBaseFilesystemAction<FILE>
     *******************************************************************************/
    public abstract InputStream readFile(FILE file) throws IOException;
 
+   /***************************************************************************
+    ** Legacy signature for this method - before table & record params were added.
+    ***************************************************************************/
+   @Deprecated(since = "call the overload that takes table and record")
+   public void writeFile(QBackendMetaData backend, String path, byte[] contents) throws IOException
+   {
+      writeFile(backend, null, null, path, contents);
+   }
+
    /*******************************************************************************
     ** Write a file - to be implemented in module-specific subclasses.
     *******************************************************************************/
-   public abstract void writeFile(QBackendMetaData backend, String path, byte[] contents) throws IOException;
+   public abstract void writeFile(QBackendMetaData backend, QTableMetaData table, QRecord record, String path, byte[] contents) throws IOException;
 
    /*******************************************************************************
     ** Get a string that represents the full path to a file.
@@ -632,7 +641,7 @@ public abstract class AbstractBaseFilesystemAction<FILE>
                try
                {
                   String fullPath = stripDuplicatedSlashes(getFullBasePath(table, backend) + File.separator + record.getValueString(tableDetails.getFileNameFieldName()));
-                  writeFile(backend, fullPath, record.getValueByteArray(tableDetails.getContentsFieldName()));
+                  writeFile(backend, table, record, fullPath, record.getValueByteArray(tableDetails.getContentsFieldName()));
                   record.addBackendDetail(FilesystemRecordBackendDetailFields.FULL_PATH, fullPath);
                   output.addRecord(record);
                }

qqq-backend-module-filesystem/src/main/java/com/kingsrook/qqq/backend/module/filesystem/local/actions/AbstractFilesystemAction.java

@@ -44,6 +44,7 @@ import com.kingsrook.qqq.backend.core.logging.QLogger;
 import com.kingsrook.qqq.backend.core.model.actions.tables.query.QCriteriaOperator;
 import com.kingsrook.qqq.backend.core.model.actions.tables.query.QFilterCriteria;
 import com.kingsrook.qqq.backend.core.model.actions.tables.query.QQueryFilter;
+import com.kingsrook.qqq.backend.core.model.data.QRecord;
 import com.kingsrook.qqq.backend.core.model.metadata.QBackendMetaData;
 import com.kingsrook.qqq.backend.core.model.metadata.QInstance;
 import com.kingsrook.qqq.backend.core.model.metadata.tables.QTableMetaData;
@@ -204,7 +205,7 @@ public class AbstractFilesystemAction extends AbstractBaseFilesystemAction<File>
     ** Write a file - to be implemented in module-specific subclasses.
     *******************************************************************************/
    @Override
-   public void writeFile(QBackendMetaData backend, String path, byte[] contents) throws IOException
+   public void writeFile(QBackendMetaData backend, QTableMetaData table, QRecord record, String path, byte[] contents) throws IOException
    {
       FileUtils.writeByteArrayToFile(new File(path), contents);
    }

qqq-backend-module-filesystem/src/main/java/com/kingsrook/qqq/backend/module/filesystem/processes/implementations/filesystem/importer/FilesystemImporterStep.java

@@ -363,7 +363,7 @@ public class FilesystemImporterStep implements BackendStep
       path = AbstractBaseFilesystemAction.stripDuplicatedSlashes(path);
 
       LOG.info("Archiving file", logPair("path", path), logPair("archiveBackendName", archiveBackend.getName()), logPair("archiveTableName", archiveTable.getName()));
-      archiveActionBase.writeFile(archiveBackend, path, bytes);
+      archiveActionBase.writeFile(archiveBackend, archiveTable, null, path, bytes);
 
       return (path);
    }

qqq-backend-module-filesystem/src/main/java/com/kingsrook/qqq/backend/module/filesystem/processes/implementations/filesystem/sync/FilesystemSyncStep.java

@@ -111,10 +111,10 @@ public class FilesystemSyncStep implements BackendStep
                   byte[] bytes = inputStream.readAllBytes();
 
                   String archivePath = archiveActionBase.getFullBasePath(archiveTable, archiveBackend);
-                  archiveActionBase.writeFile(archiveBackend, archivePath + File.separator + sourceFileName, bytes);
+                  archiveActionBase.writeFile(archiveBackend, archiveTable, null, archivePath + File.separator + sourceFileName, bytes);
 
                   String processingPath = processingActionBase.getFullBasePath(processingTable, processingBackend);
-                  processingActionBase.writeFile(processingBackend, processingPath + File.separator + sourceFileName, bytes);
+                  processingActionBase.writeFile(processingBackend, processingTable, null, processingPath + File.separator + sourceFileName, bytes);
                   syncedFileCount++;
 
                   if(maxFilesToSync != null && syncedFileCount >= maxFilesToSync)

qqq-backend-module-filesystem/src/main/java/com/kingsrook/qqq/backend/module/filesystem/s3/actions/AbstractS3Action.java

@@ -24,8 +24,10 @@ package com.kingsrook.qqq.backend.module.filesystem.s3.actions;
 
 import java.io.IOException;
 import java.io.InputStream;
+import java.net.URLConnection;
 import java.time.Instant;
 import java.util.List;
+import java.util.Objects;
 import com.amazonaws.auth.AWSStaticCredentialsProvider;
 import com.amazonaws.auth.BasicAWSCredentials;
 import com.amazonaws.services.s3.AmazonS3;
@@ -34,6 +36,7 @@ import com.amazonaws.services.s3.model.S3ObjectSummary;
 import com.kingsrook.qqq.backend.core.context.QContext;
 import com.kingsrook.qqq.backend.core.exceptions.QException;
 import com.kingsrook.qqq.backend.core.logging.QLogger;
+import com.kingsrook.qqq.backend.core.model.data.QRecord;
 import com.kingsrook.qqq.backend.core.model.metadata.QBackendMetaData;
 import com.kingsrook.qqq.backend.core.model.metadata.QInstance;
 import com.kingsrook.qqq.backend.core.model.metadata.tables.QTableMetaData;
@@ -42,6 +45,7 @@ import com.kingsrook.qqq.backend.module.filesystem.base.actions.AbstractBaseFile
 import com.kingsrook.qqq.backend.module.filesystem.base.model.metadata.AbstractFilesystemTableBackendDetails;
 import com.kingsrook.qqq.backend.module.filesystem.exceptions.FilesystemException;
 import com.kingsrook.qqq.backend.module.filesystem.s3.model.metadata.S3BackendMetaData;
+import com.kingsrook.qqq.backend.module.filesystem.s3.model.metadata.S3TableBackendDetails;
 import com.kingsrook.qqq.backend.module.filesystem.s3.utils.S3Utils;
 import static com.kingsrook.qqq.backend.core.logging.LogUtils.logPair;
 
@@ -195,14 +199,27 @@ public class AbstractS3Action extends AbstractBaseFilesystemAction<S3ObjectSumma
     ** Write a file - to be implemented in module-specific subclasses.
     *******************************************************************************/
    @Override
-   public void writeFile(QBackendMetaData backendMetaData, String path, byte[] contents) throws IOException
+   public void writeFile(QBackendMetaData backendMetaData, QTableMetaData table, QRecord record, String path, byte[] contents) throws IOException
    {
       String bucketName = ((S3BackendMetaData) backendMetaData).getBucketName();
 
       try
       {
          path = stripLeadingSlash(stripDuplicatedSlashes(path));
-         getS3Utils().writeFile(bucketName, path, contents);
+         String contentType = null;
+
+         if(table.getBackendDetails() instanceof S3TableBackendDetails s3TableBackendDetails)
+         {
+            contentType = switch(Objects.requireNonNullElse(s3TableBackendDetails.getContentTypeStrategy(), S3TableBackendDetails.ContentTypeStrategy.NONE))
+            {
+               case BASED_ON_FILE_NAME -> URLConnection.guessContentTypeFromName(path);
+               case FROM_FIELD -> record == null ? null : record.getValueString(s3TableBackendDetails.getContentTypeFieldName());
+               case HARDCODED -> s3TableBackendDetails.getHardcodedContentType();
+               case NONE -> null;
+            };
+         }
+
+         getS3Utils().writeFile(bucketName, path, contents, contentType);
       }
       catch(Exception e)
       {
@@ -277,5 +294,4 @@ public class AbstractS3Action extends AbstractBaseFilesystemAction<S3ObjectSumma
       getS3Utils().moveObject(bucketName, source, destination);
    }
 
-
 }

qqq-backend-module-filesystem/src/main/java/com/kingsrook/qqq/backend/module/filesystem/s3/model/metadata/S3TableBackendDetails.java

@@ -22,6 +22,11 @@
 package com.kingsrook.qqq.backend.module.filesystem.s3.model.metadata;
 
 
+import java.util.Objects;
+import com.kingsrook.qqq.backend.core.instances.QInstanceValidator;
+import com.kingsrook.qqq.backend.core.model.metadata.QInstance;
+import com.kingsrook.qqq.backend.core.model.metadata.tables.QTableMetaData;
+import com.kingsrook.qqq.backend.core.utils.StringUtils;
 import com.kingsrook.qqq.backend.module.filesystem.base.model.metadata.AbstractFilesystemTableBackendDetails;
 import com.kingsrook.qqq.backend.module.filesystem.s3.S3BackendModule;
 
@@ -31,6 +36,21 @@ import com.kingsrook.qqq.backend.module.filesystem.s3.S3BackendModule;
  *******************************************************************************/
 public class S3TableBackendDetails extends AbstractFilesystemTableBackendDetails
 {
+   private ContentTypeStrategy contentTypeStrategy = ContentTypeStrategy.NONE;
+   private String contentTypeFieldName;
+   private String hardcodedContentType;
+
+
+   /***************************************************************************
+    **
+    ***************************************************************************/
+   public enum ContentTypeStrategy
+   {
+      BASED_ON_FILE_NAME,
+      FROM_FIELD,
+      HARDCODED,
+      NONE
+   }
 
 
 
@@ -43,4 +63,131 @@ public class S3TableBackendDetails extends AbstractFilesystemTableBackendDetails
       setBackendType(S3BackendModule.class);
    }
 
+
+
+   /***************************************************************************
+    **
+    ***************************************************************************/
+   @Override
+   public void validate(QInstance qInstance, QTableMetaData table, QInstanceValidator qInstanceValidator)
+   {
+      super.validate(qInstance, table, qInstanceValidator);
+
+      String prefix = "Table " + (table == null ? "null" : table.getName()) + " backend details - ";
+      switch (Objects.requireNonNullElse(contentTypeStrategy, ContentTypeStrategy.NONE))
+      {
+         case BASED_ON_FILE_NAME, NONE ->
+         {
+            qInstanceValidator.assertCondition(!StringUtils.hasContent(contentTypeFieldName), prefix + "contentTypeFieldName should not be set when contentTypeStrategy is " + contentTypeStrategy);
+            qInstanceValidator.assertCondition(!StringUtils.hasContent(hardcodedContentType), prefix + "hardcodedContentType should not be set when contentTypeStrategy is " + contentTypeStrategy);
+         }
+         case FROM_FIELD ->
+         {
+            qInstanceValidator.assertCondition(!StringUtils.hasContent(hardcodedContentType), prefix + "hardcodedContentType should not be set when contentTypeStrategy is " + contentTypeStrategy);
+
+            if(table != null && qInstanceValidator.assertCondition(StringUtils.hasContent(contentTypeFieldName), prefix + "contentTypeFieldName must be set when contentTypeStrategy is " + contentTypeStrategy))
+            {
+               qInstanceValidator.assertCondition(table.getFields().containsKey(contentTypeFieldName), prefix + "contentTypeFieldName must be a valid field name in the table");
+            }
+         }
+         case HARDCODED ->
+         {
+            qInstanceValidator.assertCondition(!StringUtils.hasContent(contentTypeFieldName), prefix + "contentTypeFieldName should not be set when contentTypeStrategy is " + contentTypeStrategy);
+            qInstanceValidator.assertCondition(StringUtils.hasContent(hardcodedContentType), prefix + "hardcodedContentType must be set when contentTypeStrategy is " + contentTypeStrategy);
+         }
+      }
+   }
+
+   /*******************************************************************************
+    ** Getter for contentTypeStrategy
+    *******************************************************************************/
+   public ContentTypeStrategy getContentTypeStrategy()
+   {
+      return (this.contentTypeStrategy);
+   }
+
+
+
+   /*******************************************************************************
+    ** Setter for contentTypeStrategy
+    *******************************************************************************/
+   public void setContentTypeStrategy(ContentTypeStrategy contentTypeStrategy)
+   {
+      this.contentTypeStrategy = contentTypeStrategy;
+   }
+
+
+
+   /*******************************************************************************
+    ** Fluent setter for contentTypeStrategy
+    *******************************************************************************/
+   public S3TableBackendDetails withContentTypeStrategy(ContentTypeStrategy contentTypeStrategy)
+   {
+      this.contentTypeStrategy = contentTypeStrategy;
+      return (this);
+   }
+
+
+
+   /*******************************************************************************
+    ** Getter for contentTypeFieldName
+    *******************************************************************************/
+   public String getContentTypeFieldName()
+   {
+      return (this.contentTypeFieldName);
+   }
+
+
+
+   /*******************************************************************************
+    ** Setter for contentTypeFieldName
+    *******************************************************************************/
+   public void setContentTypeFieldName(String contentTypeFieldName)
+   {
+      this.contentTypeFieldName = contentTypeFieldName;
+   }
+
+
+
+   /*******************************************************************************
+    ** Fluent setter for contentTypeFieldName
+    *******************************************************************************/
+   public S3TableBackendDetails withContentTypeFieldName(String contentTypeFieldName)
+   {
+      this.contentTypeFieldName = contentTypeFieldName;
+      return (this);
+   }
+
+
+
+   /*******************************************************************************
+    ** Getter for hardcodedContentType
+    *******************************************************************************/
+   public String getHardcodedContentType()
+   {
+      return (this.hardcodedContentType);
+   }
+
+
+
+   /*******************************************************************************
+    ** Setter for hardcodedContentType
+    *******************************************************************************/
+   public void setHardcodedContentType(String hardcodedContentType)
+   {
+      this.hardcodedContentType = hardcodedContentType;
+   }
+
+
+
+   /*******************************************************************************
+    ** Fluent setter for hardcodedContentType
+    *******************************************************************************/
+   public S3TableBackendDetails withHardcodedContentType(String hardcodedContentType)
+   {
+      this.hardcodedContentType = hardcodedContentType;
+      return (this);
+   }
+
+
 }

qqq-backend-module-filesystem/src/main/java/com/kingsrook/qqq/backend/module/filesystem/s3/utils/S3Utils.java

@@ -204,10 +204,11 @@ public class S3Utils
    /*******************************************************************************
     ** Write a file
     *******************************************************************************/
-   public void writeFile(String bucket, String key, byte[] contents)
+   public void writeFile(String bucket, String key, byte[] contents, String contentType)
    {
       ObjectMetadata objectMetadata = new ObjectMetadata();
       objectMetadata.setContentLength(contents.length);
+      objectMetadata.setContentType(contentType);
       getAmazonS3().putObject(bucket, key, new ByteArrayInputStream(contents), objectMetadata);
    }
 

qqq-backend-module-filesystem/src/main/java/com/kingsrook/qqq/backend/module/filesystem/sftp/actions/AbstractSFTPAction.java

@@ -372,7 +372,7 @@ public class AbstractSFTPAction extends AbstractBaseFilesystemAction<SFTPDirEntr
     **
     ***************************************************************************/
    @Override
-   public void writeFile(QBackendMetaData backend, String path, byte[] contents) throws IOException
+   public void writeFile(QBackendMetaData backend, QTableMetaData table, QRecord record, String path, byte[] contents) throws IOException
    {
       sftpClient.put(new ByteArrayInputStream(contents), path);
    }

qqq-backend-module-filesystem/src/test/java/com/kingsrook/qqq/backend/module/filesystem/TestUtils.java

@@ -362,6 +362,7 @@ public class TestUtils
          .withField(new QFieldMetaData("fileName", QFieldType.STRING))
          .withField(new QFieldMetaData("contents", QFieldType.BLOB))
          .withBackendDetails(new S3TableBackendDetails()
+            .withContentTypeStrategy(S3TableBackendDetails.ContentTypeStrategy.BASED_ON_FILE_NAME)
             .withBasePath("blobs")
             .withCardinality(Cardinality.ONE)
             .withFileNameFieldName("fileName")

qqq-backend-module-filesystem/src/test/java/com/kingsrook/qqq/backend/module/filesystem/processes/implementations/filesystem/sync/FilesystemSyncProcessS3Test.java

@@ -229,7 +229,7 @@ class FilesystemSyncProcessS3Test extends BaseS3Test
       AbstractS3Action actionBase = (AbstractS3Action) module.getActionBase();
       String           fullPath   = actionBase.getFullBasePath(table, backend);
 
-      actionBase.writeFile(backend, fullPath + "/" + name, content.getBytes());
+      actionBase.writeFile(backend, table, null, fullPath + "/" + name, content.getBytes());
    }
 
 

qqq-backend-module-filesystem/src/test/java/com/kingsrook/qqq/backend/module/filesystem/s3/actions/S3InsertActionTest.java

@@ -25,7 +25,9 @@ package com.kingsrook.qqq.backend.module.filesystem.s3.actions;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.util.List;
+import com.amazonaws.services.s3.model.ObjectMetadata;
 import com.amazonaws.services.s3.model.S3Object;
+import com.kingsrook.qqq.backend.core.context.QContext;
 import com.kingsrook.qqq.backend.core.exceptions.QException;
 import com.kingsrook.qqq.backend.core.model.actions.tables.insert.InsertInput;
 import com.kingsrook.qqq.backend.core.model.actions.tables.insert.InsertOutput;
@@ -34,6 +36,7 @@ import com.kingsrook.qqq.backend.core.model.metadata.QInstance;
 import com.kingsrook.qqq.backend.module.filesystem.TestUtils;
 import com.kingsrook.qqq.backend.module.filesystem.base.FilesystemRecordBackendDetailFields;
 import com.kingsrook.qqq.backend.module.filesystem.s3.BaseS3Test;
+import com.kingsrook.qqq.backend.module.filesystem.s3.model.metadata.S3TableBackendDetails;
 import org.apache.commons.io.IOUtils;
 import org.apache.commons.lang.NotImplementedException;
 import org.junit.jupiter.api.Test;
@@ -54,18 +57,15 @@ public class S3InsertActionTest extends BaseS3Test
    @Test
    public void testCardinalityOne() throws QException, IOException
    {
-      QInstance qInstance = TestUtils.defineInstance();
-
       InsertInput insertInput = new InsertInput();
       insertInput.setTableName(TestUtils.TABLE_NAME_BLOB_S3);
       insertInput.setRecords(List.of(
-         new QRecord().withValue("fileName", "file2.txt").withValue("contents", "Hi, Bob.")
+         new QRecord().withValue("fileName", "file2.txt").withValue("contents", "Hi, Bob.")));
-      ));
 
       S3InsertAction insertAction = new S3InsertAction();
       insertAction.setS3Utils(getS3Utils());
-
       InsertOutput insertOutput = insertAction.execute(insertInput);
+
       assertThat(insertOutput.getRecords())
          .allMatch(record -> record.getBackendDetailString(FilesystemRecordBackendDetailFields.FULL_PATH).contains("blobs"));
 
@@ -73,6 +73,65 @@ public class S3InsertActionTest extends BaseS3Test
       S3Object     object   = getAmazonS3().getObject(BUCKET_NAME, fullPath);
       List<String> lines    = IOUtils.readLines(object.getObjectContent(), StandardCharsets.UTF_8);
       assertEquals("Hi, Bob.", lines.get(0));
+
+      ObjectMetadata objectMetadata = object.getObjectMetadata();
+      assertEquals("text/plain", objectMetadata.getContentType());
+   }
+
+
+
+   /*******************************************************************************
+    **
+    *******************************************************************************/
+   @Test
+   void testContentTypeFromField() throws QException
+   {
+      ((S3TableBackendDetails) QContext.getQInstance().getTable(TestUtils.TABLE_NAME_BLOB_S3)
+         .getBackendDetails())
+         .withContentTypeStrategy(S3TableBackendDetails.ContentTypeStrategy.FROM_FIELD)
+         .withContentTypeFieldName("contentType");
+
+      InsertInput insertInput = new InsertInput();
+      insertInput.setTableName(TestUtils.TABLE_NAME_BLOB_S3);
+      insertInput.setRecords(List.of(
+         new QRecord().withValue("fileName", "file2.txt").withValue("contentType", "myContentType/fake").withValue("contents", "Hi, Bob.")));
+
+      S3InsertAction insertAction = new S3InsertAction();
+      insertAction.setS3Utils(getS3Utils());
+      InsertOutput insertOutput = insertAction.execute(insertInput);
+
+      String   fullPath = insertOutput.getRecords().get(0).getBackendDetailString(FilesystemRecordBackendDetailFields.FULL_PATH);
+      S3Object object   = getAmazonS3().getObject(BUCKET_NAME, fullPath);
+      ObjectMetadata objectMetadata = object.getObjectMetadata();
+      assertEquals("myContentType/fake", objectMetadata.getContentType());
+   }
+
+
+
+   /*******************************************************************************
+    **
+    *******************************************************************************/
+   @Test
+   void testContentTypeHardcoded() throws QException
+   {
+      ((S3TableBackendDetails) QContext.getQInstance().getTable(TestUtils.TABLE_NAME_BLOB_S3)
+         .getBackendDetails())
+         .withContentTypeStrategy(S3TableBackendDetails.ContentTypeStrategy.HARDCODED)
+         .withHardcodedContentType("your-content-type");
+
+      InsertInput insertInput = new InsertInput();
+      insertInput.setTableName(TestUtils.TABLE_NAME_BLOB_S3);
+      insertInput.setRecords(List.of(
+         new QRecord().withValue("fileName", "file2.txt").withValue("contents", "Hi, Bob.")));
+
+      S3InsertAction insertAction = new S3InsertAction();
+      insertAction.setS3Utils(getS3Utils());
+      InsertOutput insertOutput = insertAction.execute(insertInput);
+
+      String   fullPath = insertOutput.getRecords().get(0).getBackendDetailString(FilesystemRecordBackendDetailFields.FULL_PATH);
+      S3Object object   = getAmazonS3().getObject(BUCKET_NAME, fullPath);
+      ObjectMetadata objectMetadata = object.getObjectMetadata();
+      assertEquals("your-content-type", objectMetadata.getContentType());
    }
 
 

qqq-backend-module-filesystem/src/test/java/com/kingsrook/qqq/backend/module/filesystem/s3/model/metadata/S3TableBackendDetailsTest.java

@@ -0,0 +1,177 @@
+/*
+ * QQQ - Low-code Application Framework for Engineers.
+ * Copyright (C) 2021-2025.  Kingsrook, LLC
+ * 651 N Broad St Ste 205 # 6917 | Middletown DE 19709 | United States
+ * contact@kingsrook.com
+ * https://github.com/Kingsrook/
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.kingsrook.qqq.backend.module.filesystem.s3.model.metadata;
+
+
+import java.util.List;
+import com.kingsrook.qqq.backend.core.context.QContext;
+import com.kingsrook.qqq.backend.core.instances.QInstanceValidator;
+import com.kingsrook.qqq.backend.core.model.metadata.fields.QFieldMetaData;
+import com.kingsrook.qqq.backend.core.model.metadata.fields.QFieldType;
+import com.kingsrook.qqq.backend.core.model.metadata.tables.QTableMetaData;
+import com.kingsrook.qqq.backend.core.utils.collections.ListBuilder;
+import com.kingsrook.qqq.backend.module.filesystem.BaseTest;
+import com.kingsrook.qqq.backend.module.filesystem.base.model.metadata.Cardinality;
+import org.assertj.core.api.CollectionAssert;
+import org.junit.jupiter.api.Test;
+
+
+/*******************************************************************************
+ ** Unit test for S3TableBackendDetails 
+ *******************************************************************************/
+class S3TableBackendDetailsTest extends BaseTest
+{
+
+   /*******************************************************************************
+    **
+    *******************************************************************************/
+   @Test
+   void testValidateContentTypeStrategyBasedOnFileNameOrNone()
+   {
+      /////////////////////////////////////////////
+      // same validation rules for both of these //
+      /////////////////////////////////////////////
+      for(S3TableBackendDetails.ContentTypeStrategy contentTypeStrategy : ListBuilder.of(null, S3TableBackendDetails.ContentTypeStrategy.BASED_ON_FILE_NAME, S3TableBackendDetails.ContentTypeStrategy.NONE))
+      {
+         S3TableBackendDetails s3TableBackendDetails = getS3TableBackendDetails()
+            .withContentTypeStrategy(contentTypeStrategy);
+         QTableMetaData table = getQTableMetaData();
+
+         List<String> errors = runValidation(s3TableBackendDetails, table);
+         CollectionAssert.assertThatCollection(errors)
+            .isEmpty();
+
+         s3TableBackendDetails.setHardcodedContentType("Test");
+         s3TableBackendDetails.setContentTypeFieldName("Test");
+         errors = runValidation(s3TableBackendDetails, table);
+         CollectionAssert.assertThatCollection(errors)
+            .hasSize(2)
+            .contains("Table testTable backend details - contentTypeFieldName should not be set when contentTypeStrategy is " + contentTypeStrategy)
+            .contains("Table testTable backend details - hardcodedContentType should not be set when contentTypeStrategy is " + contentTypeStrategy);
+      }
+   }
+
+
+
+   /*******************************************************************************
+    **
+    *******************************************************************************/
+   @Test
+   void testValidateContentTypeStrategyFromField()
+   {
+      S3TableBackendDetails s3TableBackendDetails = getS3TableBackendDetails()
+         .withContentTypeStrategy(S3TableBackendDetails.ContentTypeStrategy.FROM_FIELD);
+      QTableMetaData table = getQTableMetaData();
+
+      List<String> errors = runValidation(s3TableBackendDetails, table);
+      CollectionAssert.assertThatCollection(errors)
+         .hasSize(1)
+         .contains("Table testTable backend details - contentTypeFieldName must be set when contentTypeStrategy is FROM_FIELD");
+
+      s3TableBackendDetails.setContentTypeFieldName("notAField");
+      errors = runValidation(s3TableBackendDetails, table);
+      CollectionAssert.assertThatCollection(errors)
+         .hasSize(1)
+         .contains("Table testTable backend details - contentTypeFieldName must be a valid field name in the table");
+
+      table.addField(new QFieldMetaData("contentType", QFieldType.STRING));
+      s3TableBackendDetails.setContentTypeFieldName("contentType");
+      errors = runValidation(s3TableBackendDetails, table);
+      CollectionAssert.assertThatCollection(errors)
+         .isEmpty();
+
+      s3TableBackendDetails.setHardcodedContentType("hard");
+      errors = runValidation(s3TableBackendDetails, table);
+      CollectionAssert.assertThatCollection(errors)
+         .hasSize(1)
+         .contains("Table testTable backend details - hardcodedContentType should not be set when contentTypeStrategy is FROM_FIELD");
+   }
+
+
+
+   /*******************************************************************************
+    **
+    *******************************************************************************/
+   @Test
+   void testValidateContentTypeStrategyHardcoded()
+   {
+      S3TableBackendDetails s3TableBackendDetails = getS3TableBackendDetails()
+         .withContentTypeStrategy(S3TableBackendDetails.ContentTypeStrategy.HARDCODED);
+      QTableMetaData table = getQTableMetaData();
+
+      List<String> errors = runValidation(s3TableBackendDetails, table);
+      CollectionAssert.assertThatCollection(errors)
+         .hasSize(1)
+         .contains("Table testTable backend details - hardcodedContentType must be set when contentTypeStrategy is HARDCODED");
+
+      s3TableBackendDetails.setHardcodedContentType("Test");
+      errors = runValidation(s3TableBackendDetails, table);
+      CollectionAssert.assertThatCollection(errors)
+         .isEmpty();
+
+      s3TableBackendDetails.setContentTypeFieldName("aField");
+      errors = runValidation(s3TableBackendDetails, table);
+      CollectionAssert.assertThatCollection(errors)
+         .hasSize(1)
+         .contains("Table testTable backend details - contentTypeFieldName should not be set when contentTypeStrategy is HARDCODED");
+   }
+
+
+
+   /***************************************************************************
+    **
+    ***************************************************************************/
+   private static QTableMetaData getQTableMetaData()
+   {
+      QTableMetaData table = new QTableMetaData()
+         .withName("testTable")
+         .withField(new QFieldMetaData("contents", QFieldType.BLOB))
+         .withField(new QFieldMetaData("fileName", QFieldType.STRING));
+      return table;
+   }
+
+
+
+   /***************************************************************************
+    **
+    ***************************************************************************/
+   private static S3TableBackendDetails getS3TableBackendDetails()
+   {
+      S3TableBackendDetails s3TableBackendDetails = new S3TableBackendDetails()
+         .withContentsFieldName("contents")
+         .withFileNameFieldName("fileName")
+         .withCardinality(Cardinality.ONE);
+      return s3TableBackendDetails;
+   }
+
+
+
+   /***************************************************************************
+    **
+    ***************************************************************************/
+   private List<String> runValidation(S3TableBackendDetails s3TableBackendDetails, QTableMetaData table)
+   {
+      QInstanceValidator validator = new QInstanceValidator();
+      s3TableBackendDetails.validate(QContext.getQInstance(), table, validator);
+      return (validator.getErrors());
+   }
+}