Added "original copy indicator file", which prevents the node from deleting its own published content when storage space runs out.

Since some files won't have any mirrors, this prevents the cleanup manager from deleting the only copy in existence when freeing up space. This feature can be disabled by setting "originalCopyIndicatorFileEnabled": false in settings.json (or by deleting the ".original" files). The trade off is that the only copy in existence could be deleted if space gets low.

This will also allow for better reporting of own vs third party files in the local UI (not yet implemented).

src/main/java/org/qortal/controller/arbitrary/ArbitraryDataCleanupManager.java

@@ -18,6 +18,7 @@ import org.qortal.utils.NTP;
 
 import java.io.File;
 import java.io.IOException;
+import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.security.SecureRandom;
@@ -358,6 +359,16 @@ public class ArbitraryDataCleanupManager extends Thread {
 
 			// If it's a file, we might be able to delete it
 			if (randomItem.isFile()) {
+
+				// If the parent directory contains an ".original" file, don't delete anything
+				// This indicates that the content was originally updated by this node and so
+				// could be the only copy that exists.
+				Path originalCopyIndicatorPath = Paths.get(randomItem.getParent(), ".original");
+				if (Files.exists(originalCopyIndicatorPath)) {
+					// This is an original seed copy and so shouldn't be deleted
+					return false;
+				}
+
 				if (name != null) {
 					// A name has been specified, so we need to make sure this file relates to
 					// the name we want to delete. The signature should be the name of parent directory.

src/main/java/org/qortal/settings/Settings.java

@@ -289,6 +289,10 @@ public class Settings {
 	/** Whether to allow data outside of the storage policy to be relayed between other peers */
 	private boolean relayModeEnabled = false;
 
+	/** Whether to remember which data was originally uploaded using this node.
+	 * This prevents auto deletion of own files when storage limits are reached. */
+	private boolean originalCopyIndicatorFileEnabled = true;
+
 	/** Whether to make connections directly with peers that have the required data */
 	private boolean directDataRetrievalEnabled = true;
 
@@ -861,6 +865,10 @@ public class Settings {
 		return this.directDataRetrievalEnabled;
 	}
 
+	public boolean isOriginalCopyIndicatorFileEnabled() {
+		return this.originalCopyIndicatorFileEnabled;
+	}
+
 	public Long getBuiltDataExpiryInterval() {
 		return this.builtDataExpiryInterval;
 	}

src/main/java/org/qortal/utils/ArbitraryTransactionUtils.java

@@ -9,10 +9,13 @@ import org.qortal.data.transaction.ArbitraryTransactionData;
 import org.qortal.data.transaction.TransactionData;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
+import org.qortal.settings.Settings;
 
+import java.io.File;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.nio.file.attribute.BasicFileAttributes;
 import java.util.Arrays;
 
@@ -327,6 +330,19 @@ public class ArbitraryTransactionUtils {
                 // Delete empty parent directories
                 FilesystemUtils.safeDeleteEmptyParentDirectories(oldPath);
             }
+
+            // If at least one file was relocated, we can assume that the data from this transaction
+            // originated from this node
+            if (filesRelocatedCount > 0) {
+                if (Settings.getInstance().isOriginalCopyIndicatorFileEnabled()) {
+                    // Create a file in the same directory, to indicate that this is the original copy
+                    LOGGER.info("Creating original copy indicator file...");
+                    ArbitraryDataFile completeFile = ArbitraryDataFile.fromHash(arbitraryDataFile.getHash(), signature);
+                    Path parentDirectory = completeFile.getFilePath().getParent();
+                    File file = Paths.get(parentDirectory.toString(), ".original").toFile();
+                    file.createNewFile();
+                }
+            }
         }
         catch (DataException | IOException e) {
             LOGGER.info("Unable to check and relocate all files for signature {}: {}",