some last touches. #12070

Author: landreev

doc/release-notes/12070-datacite-getmetadata.md

@@ -1,4 +1,4 @@
-Incremental improvements have been made to the process of registering dataset metadata with DataCite. If your instance is using DataCite, please make sure you have the DataCite REST API url configured, since it is now required.
+Incremental improvements have been made to the process of registering dataset metadata with DataCite. If your instance is using DataCite, please make sure you have a valid DataCite REST API url configured, since it is now required.
 
 The JVM option(s) in question are `dataverse.pid.*.datacite.rest-api-url` if the recommended, new-style pid configuration is used, or `doi.dataciterestapiurlstring` if the legacy settings are in place. In the latter case however, this may be a good occasion to switch to the new configuration setup.
 

src/main/java/edu/harvard/iq/dataverse/pidproviders/doi/datacite/DOIDataCiteRegisterService.java

@@ -87,7 +87,7 @@ public String reRegisterIdentifier(String identifier, Map<String, String> metada
         String currentMetadata = null;
         boolean hasDifferences = false;
         try {
-            currentMetadata = client.getMetadataViaRestApi(bareIdentifier);
+            currentMetadata = client.getMetadata(bareIdentifier);
             Diff myDiff = DiffBuilder.compare(xmlMetadata).withTest(currentMetadata).ignoreWhitespace().checkForSimilar()
                     .build();
             hasDifferences = myDiff.hasDifferences();

src/main/java/edu/harvard/iq/dataverse/pidproviders/doi/datacite/DataCiteRESTfullClient.java

@@ -194,6 +194,13 @@ public String postUrl(String doi, String url) throws IOException {
      * @return
      */
     public String getMetadata(String doi) {
+        // Try obtaining the metadata using the new, REST API:
+        try {
+            return getMetadataViaRestApi(doi);
+        } catch (RuntimeException rex) {
+            logger.warning("Failed to getMetadata via REST API for doi " + doi +", falling back to MDS");
+        }
+        
         HttpGet httpGet = new HttpGet(this.url + "/metadata/" + doi);
         httpGet.setHeader("Accept", "application/xml");
         try {