diff --git a/dspace-api/src/main/java/org/dspace/importer/external/scopus/service/ScopusImportMetadataSourceServiceImpl.java b/dspace-api/src/main/java/org/dspace/importer/external/scopus/service/ScopusImportMetadataSourceServiceImpl.java index 944d467e31..e61ca05286 100644 --- a/dspace-api/src/main/java/org/dspace/importer/external/scopus/service/ScopusImportMetadataSourceServiceImpl.java +++ b/dspace-api/src/main/java/org/dspace/importer/external/scopus/service/ScopusImportMetadataSourceServiceImpl.java @@ -14,6 +14,7 @@ import java.io.StringReader; import java.util.ArrayList; import java.util.Arrays; import java.util.Collection; +import java.util.Collections; import java.util.HashMap; import java.util.List; import java.util.Map; @@ -24,6 +25,8 @@ import java.util.regex.Pattern; import javax.el.MethodNotFoundException; import org.apache.commons.lang3.StringUtils; +import org.apache.logging.log4j.LogManager; +import org.apache.logging.log4j.Logger; import org.dspace.content.Item; import org.dspace.importer.external.datamodel.ImportRecord; import org.dspace.importer.external.datamodel.Query; @@ -62,6 +65,8 @@ public class ScopusImportMetadataSourceServiceImpl extends AbstractImportMetadat @Autowired private LiveImportClient liveImportClient; + private final static Logger log = LogManager.getLogger(); + public LiveImportClient getLiveImportClient() { return liveImportClient; } @@ -200,6 +205,9 @@ public class ScopusImportMetadataSourceServiceImpl extends AbstractImportMetadat Map requestParams = getRequestParameters(query, null, null, null); params.put(URI_PARAMETERS, requestParams); String response = liveImportClient.executeHttpGetRequest(timeout, url, params); + if (StringUtils.isEmpty(response)) { + return 0; + } SAXBuilder saxBuilder = new SAXBuilder(); // disallow DTD parsing to ensure no XXE attacks can occur @@ -245,6 +253,10 @@ public class ScopusImportMetadataSourceServiceImpl extends AbstractImportMetadat Map requestParams = getRequestParameters(queryString, viewMode, null, null); params.put(URI_PARAMETERS, requestParams); String response = liveImportClient.executeHttpGetRequest(timeout, url, params); + if (StringUtils.isEmpty(response)) { + return results; + } + List elements = splitToRecords(response); for (Element record : elements) { results.add(transformSourceRecords(record)); @@ -304,6 +316,10 @@ public class ScopusImportMetadataSourceServiceImpl extends AbstractImportMetadat Map requestParams = getRequestParameters(queryString, viewMode, start, count); params.put(URI_PARAMETERS, requestParams); String response = liveImportClient.executeHttpGetRequest(timeout, url, params); + if (StringUtils.isEmpty(response)) { + return results; + } + List elements = splitToRecords(response); for (Element record : elements) { results.add(transformSourceRecords(record)); @@ -349,6 +365,10 @@ public class ScopusImportMetadataSourceServiceImpl extends AbstractImportMetadat Map requestParams = getRequestParameters(queryString, viewMode, start, count); params.put(URI_PARAMETERS, requestParams); String response = liveImportClient.executeHttpGetRequest(timeout, url, params); + if (StringUtils.isEmpty(response)) { + return results; + } + List elements = splitToRecords(response); for (Element record : elements) { results.add(transformSourceRecords(record)); @@ -383,10 +403,16 @@ public class ScopusImportMetadataSourceServiceImpl extends AbstractImportMetadat saxBuilder.setFeature("http://apache.org/xml/features/disallow-doctype-decl",true); Document document = saxBuilder.build(new StringReader(recordsSrc)); Element root = document.getRootElement(); - List records = root.getChildren("entry",Namespace.getNamespace("http://www.w3.org/2005/Atom")); + String totalResults = root.getChildText("totalResults", Namespace.getNamespace("http://a9.com/-/spec/opensearch/1.1/")); + if (totalResults != null && "0".equals(totalResults)) { + log.debug("got Scopus API with empty response"); + return Collections.emptyList(); + } + List records = root.getChildren("entry", Namespace.getNamespace("http://www.w3.org/2005/Atom")); return records; } catch (JDOMException | IOException e) { - return new ArrayList(); + log.warn("got unexpected XML response from Scopus API: " + e.getMessage()); + return Collections.emptyList(); } } @@ -422,4 +448,4 @@ public class ScopusImportMetadataSourceServiceImpl extends AbstractImportMetadat this.instKey = instKey; } -} \ No newline at end of file +}