Signposting on Dataverse 5.9

doc/release-notes/8424-signposting.md

@@ -0,0 +1,32 @@
+# Signposting for Dataverse
+
+This branch adds [Signposting](https://signposting.org/) support to Dataverse
+
+There are 2 Signposting profile levels, level 1 and level 2. In this implementation, 
+ * level 1 links are shown in 
+HTTP header, which can be fetched by `curl -I https://domain/link-to-article`. 
+ * The level 2 linkset can be fetched by visiting the dedicated linkset page for 
+   that artifact. The link can be seen in level 1 links with key name `rel="linkset"`.
+
+The configuration is stored as JSON string in the `Bundle.properties` file, key name is
+`signposting.configuration.SignpostingConf`. Please see a sample configuration below with explaination for each of the
+config items.
+
+```json
+{
+  "useDefaultFileType": true,
+  "defaultFileTypeValue": "https://schema.org/Dataset",
+  "maxItems": 5,
+  "maxAuthors": 5
+}
+```
+
+ * `useDefaultFileType` and `defaultFileTypeValue` are used in combination to provide extra `Dataset` type to DV 
+   datasets. `AboutPage` is required by `Signposting`, hence always present in the datasets. Whilst a second type 
+   could be configured to better reflect the actual scholarly type of the dataset. 
+ * `maxItems` sets the max number of items/files which will be shown in `level 1` profile. Datasets with 
+   too many files will not show any file link in `level 1` profile. They will be shown in `level 2` linkset only. 
+ * `maxAuthors` Same with `maxItems`, `maxAuthors` sets the max number of authors to be shown in `level 1` profile. 
+If amount of authors exceeds this value, no link of authors will be shown in `level 1` profile. 
+
+Note: Authors without author link will not be counted nor shown in any profile/linkset. 

src/main/java/edu/harvard/iq/dataverse/DatasetPage.java

@@ -143,6 +143,7 @@
 import edu.harvard.iq.dataverse.search.SearchServiceBean;
 import edu.harvard.iq.dataverse.search.SearchUtil;
 import edu.harvard.iq.dataverse.search.SolrClientService;
+import edu.harvard.iq.dataverse.util.SignpostingResources;
 import java.util.Comparator;
 import org.apache.solr.client.solrj.SolrQuery;
 import org.apache.solr.client.solrj.impl.HttpSolrClient;
@@ -5872,4 +5873,15 @@ public boolean downloadingRestrictedFiles() {
         }
         return false;
     }
+
+    /**
+     * Add Signposting
+     * @return String
+     */
+    public String getSignpostingLinkHeader() {
+        if (!workingVersion.isReleased())
+            return null;
+        SignpostingResources sr = new SignpostingResources(systemConfig, workingVersion, settingsService.getValueForKey(SettingsServiceBean.Key.SignpostingConf));
+        return sr.getLinks();
+    }
 }

src/main/java/edu/harvard/iq/dataverse/api/AbstractApiBean.java

@@ -850,6 +850,19 @@ protected static Response error( Status sts, String msg ) {
                         .add( "message", msg ).build()
                 ).type(MediaType.APPLICATION_JSON_TYPE).build();
     }
+
+    /**
+     * Adding Signposting
+     *
+     * @param bld
+     * @return HTTP OK response which contains the json structure of linkset
+     */
+    protected Response okLinkset( JsonArrayBuilder bld ) {
+        return Response.ok( Json.createObjectBuilder()
+                .add("linkset", bld).build() )
+                .type(MediaType.APPLICATION_JSON)
+                .build();
+    }
 }
 
 class LazyRef<T> {

src/main/java/edu/harvard/iq/dataverse/api/Datasets.java

@@ -86,6 +86,8 @@
 import edu.harvard.iq.dataverse.util.json.JSONLDUtil;
 import edu.harvard.iq.dataverse.util.json.JsonLDTerm;
 import edu.harvard.iq.dataverse.util.json.JsonParseException;
+import edu.harvard.iq.dataverse.util.json.JsonPrinter;
+import edu.harvard.iq.dataverse.util.SignpostingResources;
 import edu.harvard.iq.dataverse.search.IndexServiceBean;
 import static edu.harvard.iq.dataverse.util.json.JsonPrinter.*;
 import static edu.harvard.iq.dataverse.util.json.NullSafeJsonBuilder.jsonObjectBuilder;
@@ -530,7 +532,31 @@ public Response getVersionMetadataBlock( @PathParam("id") String datasetId,
             return notFound("metadata block named " + blockName + " not found");
         });
     }
-
+
+    /**
+     * Add Signposting
+     * @param datasetId
+     * @param versionId
+     * @param uriInfo
+     * @param headers
+     * @return
+     */
+    @GET
+    @Path("{id}/versions/{versionId}/linkset")
+    public Response getLinkset( @PathParam("id") String datasetId, @PathParam("versionId") String versionId, @Context UriInfo uriInfo, @Context HttpHeaders headers) {
+        if ( ":draft".equals(versionId) ) {
+            return badRequest("The :draft version can be viewed");
+        }
+        return response( req -> {
+            DatasetVersion dsv = getDatasetVersionOrDie(req, versionId, findDatasetOrDie(datasetId), uriInfo, headers);
+            String dataverseSiteUrl = systemConfig.getDataverseSiteUrl();
+            String anchor = dataverseSiteUrl + "/dataset.xhtml?persistentId=" + dsv.getDataset().getPersistentURL();
+            String signpostingConf = settingsService.getValueForKey(SettingsServiceBean.Key.SignpostingConf, BundleUtil.getStringFromBundle("signposting.configuration.SignpostingConf"));
+            if (signpostingConf.isEmpty()) return notFound("Configuration key for signposting is empty [SignpostingConf]");
+            if (dsv.getId() == null) return notFound("Dataset not found: Id is empty");
+            return okLinkset(JsonPrinter.jsonLinkset(new SignpostingResources(systemConfig, dsv, signpostingConf)));
+        });
+    }
     @GET
     @Path("{id}/modifyRegistration")
     public Response updateDatasetTargetURL(@PathParam("id") String id ) {

src/main/java/edu/harvard/iq/dataverse/settings/SettingsServiceBean.java

@@ -198,6 +198,11 @@ public enum Key {
          */
         MetricsUrl,
 
+        /**
+         * Key for Setting of Signposting
+         */
+        SignpostingConf,
+
         /**
          * Number of minutes before a metrics query can be rerun. Otherwise a cached value is returned.
          * Previous month dates always return cache. Only applies to new internal caching system (not miniverse).