/arbitrary/metadata/* endpoint now returns ArbitraryResourceMetadata rather than a raw JSON string.

src/main/java/org/qortal/api/resource/ArbitraryResource.java

@@ -694,7 +694,7 @@ public class ArbitraryResource {
 			}
 	)
 	@SecurityRequirement(name = "apiKey")
-	public String getMetadata(@HeaderParam(Security.API_KEY_HEADER) String apiKey,
+	public ArbitraryResourceMetadata getMetadata(@HeaderParam(Security.API_KEY_HEADER) String apiKey,
 							  @PathParam("service") Service service,
 							  @PathParam("name") String name,
 							  @PathParam("identifier") String identifier) {
@@ -703,12 +703,20 @@ public class ArbitraryResource {
 		ArbitraryDataResource resource = new ArbitraryDataResource(name, ResourceIdType.NAME, service, identifier);
 
 		try {
-			byte[] metadata = ArbitraryMetadataManager.getInstance().fetchMetadata(resource, false);
+			ArbitraryDataTransactionMetadata transactionMetadata = ArbitraryMetadataManager.getInstance().fetchMetadata(resource, false);
-			if (metadata != null) {
+			if (transactionMetadata != null) {
-				return new String(metadata, StandardCharsets.UTF_8);
+				ArbitraryResourceMetadata resourceMetadata = ArbitraryResourceMetadata.fromTransactionMetadata(transactionMetadata);
+				if (resourceMetadata != null) {
+					return resourceMetadata;
+				}
+				else {
+					// The metadata file doesn't contain title, description, category, or tags
+					throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FILE_NOT_FOUND);
+				}
 			}
 		} catch (IllegalArgumentException e) {
-			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, e.getMessage());
+			// No metadata exists for this resource
+			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.FILE_NOT_FOUND, e.getMessage());
 		}
 
 		throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_DATA);
@@ -1279,7 +1287,7 @@ public class ArbitraryResource {
 			ArbitraryDataTransactionMetadata transactionMetadata = resource.getLatestTransactionMetadata();
 			ArbitraryResourceMetadata resourceMetadata = ArbitraryResourceMetadata.fromTransactionMetadata(transactionMetadata);
 			if (resourceMetadata != null) {
-				resourceInfo.metadata = ArbitraryResourceMetadata.fromTransactionMetadata(transactionMetadata);
+				resourceInfo.metadata = resourceMetadata;
 			}
 			updatedResources.add(resourceInfo);
 		}

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

@@ -9,6 +9,7 @@ import org.apache.logging.log4j.Logger;
 import org.qortal.api.resource.TransactionsResource.ConfirmationStatus;
 import org.qortal.arbitrary.ArbitraryDataFile;
 import org.qortal.arbitrary.ArbitraryDataResource;
+import org.qortal.arbitrary.metadata.ArbitraryDataTransactionMetadata;
 import org.qortal.arbitrary.misc.Service;
 import org.qortal.controller.Controller;
 import org.qortal.data.network.ArbitraryPeerData;
@@ -349,7 +350,7 @@ public class ArbitraryDataManager extends Thread {
 	}
 
 	// Entrypoint to request new metadata from peers
-	public byte[] fetchMetadata(ArbitraryTransactionData arbitraryTransactionData) {
+	public ArbitraryDataTransactionMetadata fetchMetadata(ArbitraryTransactionData arbitraryTransactionData) {
 
 		ArbitraryDataResource resource = new ArbitraryDataResource(
 				arbitraryTransactionData.getName(),

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

@@ -4,6 +4,7 @@ import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.qortal.arbitrary.ArbitraryDataFile;
 import org.qortal.arbitrary.ArbitraryDataResource;
+import org.qortal.arbitrary.metadata.ArbitraryDataTransactionMetadata;
 import org.qortal.controller.Controller;
 import org.qortal.data.transaction.ArbitraryTransactionData;
 import org.qortal.data.transaction.TransactionData;
@@ -18,6 +19,7 @@ import org.qortal.utils.Base58;
 import org.qortal.utils.NTP;
 import org.qortal.utils.Triple;
 
+import java.io.IOException;
 import java.util.*;
 
 import static org.qortal.controller.arbitrary.ArbitraryDataFileListManager.RELAY_REQUEST_MAX_DURATION;
@@ -75,7 +77,7 @@ public class ArbitraryMetadataManager {
     }
 
 
-    public byte[] fetchMetadata(ArbitraryDataResource arbitraryDataResource, boolean useRateLimiter) {
+    public ArbitraryDataTransactionMetadata fetchMetadata(ArbitraryDataResource arbitraryDataResource, boolean useRateLimiter) {
         try (final Repository repository = RepositoryManager.getRepository()) {
             // Find latest transaction
             ArbitraryTransactionData latestTransaction = repository.getArbitraryRepository()
@@ -91,17 +93,21 @@ public class ArbitraryMetadataManager {
                 }
 
                 ArbitraryDataFile metadataFile = ArbitraryDataFile.fromHash(metadataHash, signature);
+                if (!metadataFile.exists()) {
+                    // Request from network
+                    this.fetchArbitraryMetadata(latestTransaction, useRateLimiter);
+                }
+
+                // Now check again as it may have been downloaded above
                 if (metadataFile.exists()) {
                     // Use local copy
-                    return metadataFile.getBytes();
+                    ArbitraryDataTransactionMetadata transactionMetadata = new ArbitraryDataTransactionMetadata(metadataFile.getFilePath());
-                }
+                    transactionMetadata.read();
-                else {
+                    return transactionMetadata;
-                    // Request from network
-                    return this.fetchArbitraryMetadata(latestTransaction, useRateLimiter);
                 }
             }
 
-        } catch (DataException e) {
+        } catch (DataException | IOException e) {
             LOGGER.error("Repository issue when fetching arbitrary transaction metadata", e);
         }