feat: support draft features on existing crates

src/main/java/edu/kit/datamanager/ro_crate/Crate.java

@@ -3,13 +3,15 @@
 import java.io.File;
 import java.util.Collection;
 import java.util.List;
+import java.util.Optional;
 
 import edu.kit.datamanager.ro_crate.context.CrateMetadataContext;
 import edu.kit.datamanager.ro_crate.entities.AbstractEntity;
 import edu.kit.datamanager.ro_crate.entities.contextual.ContextualEntity;
 import edu.kit.datamanager.ro_crate.entities.data.DataEntity;
 import edu.kit.datamanager.ro_crate.entities.data.RootDataEntity;
 import edu.kit.datamanager.ro_crate.preview.CratePreview;
+import edu.kit.datamanager.ro_crate.special.CrateVersion;
 
 /**
  * An interface describing an ROCrate.
@@ -18,6 +20,33 @@
  * @version 1
  */
 public interface Crate {
+
+  /**
+   * Read version from the crate descriptor and return it as a class
+   * representation.
+   * 
+   * NOTE: If there is not version in the crate, it does not comply with the
+   * specification.
+   * 
+   * @return the class representation indication the version of this crate, if
+   *         available.
+   */
+  public Optional<CrateVersion> getVersion();
+
+  /**
+   * Returns strings indicating the conformance of a crate with other
+   * specifications than the RO-Crate version.
+   * 
+   * If you need the crate version too, refer to {@link #getVersion()}.
+   * 
+   * This corresponds technically to all conformsTo values, excluding the RO crate
+   * version / specification.
+   * 
+   * @return a collection of the profiles or specifications this crate conforms
+   *         to.
+   */
+  public Collection<String> getProfiles();
+
   CratePreview getPreview();
 
   void setMetadataContext(CrateMetadataContext metadataContext);

src/main/java/edu/kit/datamanager/ro_crate/RoCrate.java

@@ -1,5 +1,6 @@
 package edu.kit.datamanager.ro_crate;
 
+import com.fasterxml.jackson.core.TreeNode;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ObjectNode;
@@ -25,7 +26,12 @@
 import java.net.URI;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.List;
+import java.util.Optional;
+import java.util.stream.Collectors;
+import java.util.stream.StreamSupport;
+
 
 /**
  * The class that represents a single ROCrate.
@@ -101,6 +107,38 @@ public RoCrate(RoCrateBuilder roCrateBuilder) {
     defaultValidation.validate(this);
   }
 
+  @Override
+  public Optional<CrateVersion> getVersion() {
+    JsonNode conformsTo = this.jsonDescriptor.getProperty("conformsTo");
+    if (conformsTo.isArray()) {
+      return StreamSupport.stream(conformsTo.spliterator(), false)
+        .filter(TreeNode::isObject)
+        .map(obj -> obj.path("@id").asText())
+        .map(CrateVersion::fromSpecUri)
+        .filter(Optional::isPresent)
+        .map(Optional::get)
+        .findFirst();
+    } else if (conformsTo.isObject()) {
+      return CrateVersion.fromSpecUri(conformsTo.get("@id").asText());
+    } else {
+      return Optional.empty();
+    }
+  }
+
+  @Override
+  public Collection<String> getProfiles() {
+    JsonNode conformsTo = this.jsonDescriptor.getProperty("conformsTo");
+    if (conformsTo.isArray()) {
+      return StreamSupport.stream(conformsTo.spliterator(), false)
+        .filter(TreeNode::isObject)
+        .map(obj -> obj.path("@id").asText())
+        .filter(txt -> !CrateVersion.fromSpecUri(txt).isPresent())
+        .collect(Collectors.toSet());
+    } else {
+      return Collections.emptySet();
+    }
+  }
+
   @Override
   public String getJsonMetadata() {
     ObjectMapper objectMapper = MyObjectMapper.getMapper();
@@ -319,49 +357,63 @@ public RoCrate build() {
   }
 
   /**
-   * Builder for Crates, supporting all Features from v1.1 on.
-   */
-  public static class BuilderV1p1 extends RoCrateBuilder {
-    // for consistency
-  }
-
-  /**
-   * Builder for Crates, supporting all Features from v1.2 on.
+   * Builder for Crates, supporting features which are not in a final
+   * specification yet.
+   * 
+   * NOTE: This will change the specification version of your crate.
    * 
-   * NOTE: Changes may happen as this is a draft!
+   * We only add features we expect to be in the new specification in the
+   * end.
+   * In case a feature will not make it into the specification, we will mark it as
+   * deprecated and remove it in new major versions.
+   * If a feature is finalized, it will be added to the stable
+   * {@link RoCrateBuilder} and marked as deprecated in this class.
    */
-  public static class BuilderV1p2Draft extends RoCrateBuilder {
+  public static class BuilderWithDraftFeatures extends RoCrateBuilder {
 
-    JsonDescriptor.Builder descriptorBuilder = new JsonDescriptor.Builder()
-        .setVersion(CrateVersion.V1P2_DRAFT);
+    JsonDescriptor.Builder descriptorBuilder = new JsonDescriptor.Builder();
 
     /**
-     * A default constructor without any params where the root data entity will be
-     * plain.
+     * {@inheritDoc}
+     * @see RoCrateBuilder#RoCrateBuilder()
      */
-    public BuilderV1p2Draft() {
-      this.payload = new RoCratePayload();
-      this.untrackedFiles = new ArrayList<>();
-      this.metadataContext = new RoCrateMetadataContext();
-      rootDataEntity = new RootDataEntity.RootDataEntityBuilder()
-          .build();
-      jsonDescriptor = new JsonDescriptor.Builder()
-          .setVersion(CrateVersion.V1P2_DRAFT)
-          .build();
+    public BuilderWithDraftFeatures() {
+      super();
+    }
+
+    /**
+     * {@inheritDoc}
+     * @param name {@inheritDoc}
+     * @param description {@inheritDoc}
+     */
+    public BuilderWithDraftFeatures(String name, String description) {
+      super();
+    }
+
+    /**
+     * {@inheritDoc}
+     * @param crate {@inheritDoc}
+     */
+    public BuilderWithDraftFeatures(RoCrate crate) {
+      super(crate);
+      this.descriptorBuilder = new JsonDescriptor.Builder(crate);
     }
 
     /**
      * Indicate this crate also conforms to the given specification, in addition to
-     * the version this builder creates.
+     * the version this builder adds.
      * 
      * This is helpful for profiles or other specifications the crate conforms to.
      * Can be called multiple times to add more specifications.
      * 
      * @param specification a specification or profile this crate conforms to.
      * @return the builder
      */
-    public BuilderV1p2Draft alsoConformsTo(URI specification) {
-      descriptorBuilder.addConformsTo(specification);
+    public BuilderWithDraftFeatures alsoConformsTo(URI specification) {
+      descriptorBuilder
+          .addConformsTo(specification)
+          // usage of a draft feature results in draft version numbers of the crate
+          .setVersion(CrateVersion.LATEST_UNSTABLE);
       return this;
     }
 

src/main/java/edu/kit/datamanager/ro_crate/entities/contextual/JsonDescriptor.java

@@ -7,6 +7,7 @@
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ArrayNode;
 
+import edu.kit.datamanager.ro_crate.Crate;
 import edu.kit.datamanager.ro_crate.objectmapper.MyObjectMapper;
 import edu.kit.datamanager.ro_crate.special.CrateVersion;
 
@@ -45,6 +46,15 @@ public static final class Builder {
         CrateVersion version = CrateVersion.LATEST_STABLE;
         Set<String> otherConformsToValues = new HashSet<>();
 
+        public Builder() {
+            // default
+        }
+
+        public Builder(Crate crate) {
+            crate.getVersion().ifPresent(v -> this.version = v);
+            this.otherConformsToValues.addAll(crate.getProfiles());
+        }
+
         public Builder setVersion(CrateVersion version) {
             this.version = version;
             return this;

src/main/java/edu/kit/datamanager/ro_crate/special/CrateVersion.java

@@ -45,7 +45,7 @@ public enum CrateVersion {
      *                   https://w3id.org/ro/crate/1.1
      * @return the matching CrateVersion enum, if the URI matches any. Empty if not.
      */
-    public Optional<CrateVersion> fromSpecUri(String conformsTo) {
+    public static Optional<CrateVersion> fromSpecUri(String conformsTo) {
         return Optional.ofNullable(crateVersionOfConformsTo(conformsTo));
     }
 

src/test/java/edu/kit/datamanager/ro_crate/crate/BuilderSpec12Test.java

@@ -1,28 +1,82 @@
 package edu.kit.datamanager.ro_crate.crate;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.util.Collection;
 
 import org.junit.jupiter.api.Test;
 
 import com.fasterxml.jackson.databind.JsonNode;
 
 import edu.kit.datamanager.ro_crate.Crate;
 import edu.kit.datamanager.ro_crate.RoCrate;
+import edu.kit.datamanager.ro_crate.entities.contextual.ContextualEntity;
+import edu.kit.datamanager.ro_crate.reader.FolderReader;
+import edu.kit.datamanager.ro_crate.reader.RoCrateReader;
+import edu.kit.datamanager.ro_crate.special.CrateVersion;
+import edu.kit.datamanager.ro_crate.validation.JsonSchemaValidation;
+import edu.kit.datamanager.ro_crate.validation.Validator;
 
 class BuilderSpec12Test {
+    private URI profile1;
+    private URI profile2;
+
     @Test
     void testAppendConformsTo() throws URISyntaxException {
-        Crate crate = new RoCrate.BuilderV1p2Draft()
-            .alsoConformsTo(new URI("https://w3id.org/ro/wfrun/process/0.1"))
-            .alsoConformsTo(new URI("https://example.com/myprofile/1.0"))
-            .build();
+        Crate crate = new RoCrate.BuilderWithDraftFeatures()
+                .alsoConformsTo(new URI("https://w3id.org/ro/wfrun/process/0.1"))
+                .alsoConformsTo(new URI("https://example.com/myprofile/1.0"))
+                .build();
         JsonNode conformsTo = crate.getJsonDescriptor().getProperty("conformsTo");
         assertTrue(conformsTo.isArray());
         // one version and two profiles
         assertEquals(1 + 2, conformsTo.size());
     }
+
+    @Test
+    void testModificationOfDraftCrate() throws URISyntaxException {
+        String path = this.getClass().getResource("/crates/spec-1.2-DRAFT/minimal-with-conformsTo-Array").getPath();
+        RoCrate crate = new RoCrateReader(new FolderReader()).readCrate(path);
+        Collection<String> existingProfiles = crate.getProfiles();
+        profile1 = new URI("https://example.com/myprofile/1.0");
+        profile2 = new URI("https://example.com/myprofile/2.0");
+        // the loaded crate has at least one profile
+        assertFalse(existingProfiles.isEmpty());
+        // and the ones we will add later are not part of it
+        assertFalse(existingProfiles.contains(profile1.toString()));
+        assertFalse(existingProfiles.contains(profile2.toString()));
+
+        // add profiles
+        RoCrate modifiedCrate = new RoCrate.BuilderWithDraftFeatures(crate)
+                .alsoConformsTo(profile1)
+                .alsoConformsTo(profile2)
+                .addContextualEntity(new ContextualEntity.ContextualEntityBuilder()
+                        .addType("CreativeWork")
+                        .build())
+                .build();
+
+        // sanity checks
+        Validator defaultValidation = new Validator(new JsonSchemaValidation());
+        assertTrue(defaultValidation.validate(modifiedCrate));
+        assertEquals(CrateVersion.LATEST_UNSTABLE, crate.getVersion().get());
+        assertEquals(CrateVersion.LATEST_UNSTABLE, modifiedCrate.getVersion().get());
+
+        // number of profiles increased by 2
+        Collection<String> newProfileState = modifiedCrate.getProfiles();
+        assertEquals(existingProfiles.size() + 2, newProfileState.size());
+        // new profiles are present
+        newProfileState.contains(profile1.toString());
+        newProfileState.contains(profile2.toString());
+        // old profiles are present
+        assertEquals(
+            0,
+            existingProfiles.stream()
+                .filter(txt -> !newProfileState.contains(txt))
+                .count()
+        );
+    }
 }