#8630 add the changeset endpoint getAll

scm-webapp/src/main/java/sonia/scm/api/v2/resources/BasicCollectionToDtoMapper.java

@@ -11,6 +11,7 @@ import sonia.scm.PageResult;
 import javax.inject.Inject;
 import java.util.EnumSet;
 import java.util.List;
+import java.util.function.Function;
 
 import static com.damnhandy.uri.template.UriTemplate.fromTemplate;
 import static de.otto.edison.hal.Embedded.embeddedBuilder;
@@ -19,25 +20,28 @@ import static de.otto.edison.hal.Links.linkingTo;
 import static de.otto.edison.hal.paging.NumberedPaging.zeroBasedNumberedPaging;
 import static java.util.stream.Collectors.toList;
 
-abstract class BasicCollectionToDtoMapper<E extends ModelObject, D extends HalRepresentation> {
+abstract class BasicCollectionToDtoMapper<E extends ModelObject, D extends HalRepresentation, M extends BaseMapper<E, D>> {
 
   private final String collectionName;
-  private final BaseMapper<E, D> entityToDtoMapper;
+
+  protected final M entityToDtoMapper;
 
   @Inject
-  public BasicCollectionToDtoMapper(String collectionName, BaseMapper<E, D> entityToDtoMapper) {
+  public BasicCollectionToDtoMapper(String collectionName, M entityToDtoMapper) {
     this.collectionName = collectionName;
     this.entityToDtoMapper = entityToDtoMapper;
   }
 
   public CollectionDto map(int pageNumber, int pageSize, PageResult<E> pageResult) {
-    NumberedPaging paging = zeroBasedNumberedPaging(pageNumber, pageSize, pageResult.getOverallCount());
-    List<D> dtos = pageResult.getEntities().stream().map(entityToDtoMapper::map).collect(toList());
+    return map(pageNumber, pageSize, pageResult, entityToDtoMapper::map, createSelfLink());
+  }
 
+  public CollectionDto map(int pageNumber, int pageSize, PageResult<E> pageResult, Function<E, D> mapper, String selfLink) {
+    NumberedPaging paging = zeroBasedNumberedPaging(pageNumber, pageSize, pageResult.getOverallCount());
+    List<D> dtos = pageResult.getEntities().stream().map(mapper).collect(toList());
     CollectionDto collectionDto = new CollectionDto(
-      createLinks(paging),
-      embedDtos(dtos)
-    );
+      createLinks(paging, selfLink),
+      embedDtos(dtos));
     collectionDto.setPage(pageNumber);
     collectionDto.setPageTotal(computePageTotal(pageSize, pageResult));
     return collectionDto;
@@ -51,9 +55,7 @@ abstract class BasicCollectionToDtoMapper<E extends ModelObject, D extends HalRe
     }
   }
 
-  private Links createLinks(NumberedPaging page) {
-    String baseUrl = createSelfLink();
-
+  private Links createLinks(NumberedPaging page, String baseUrl) {
     Links.Builder linksBuilder = linkingTo()
       .with(page.links(
         fromTemplate(baseUrl + "{?page,pageSize}"),

scm-webapp/src/main/java/sonia/scm/api/v2/resources/BranchCollectionToDtoMapper.java

@@ -26,8 +26,11 @@ public class BranchCollectionToDtoMapper {
   }
 
   public HalRepresentation map(String namespace, String name, Collection<Branch> branches) {
-    List<BranchDto> dtos = branches.stream().map(branch -> branchToDtoMapper.map(branch, new NamespaceAndName(namespace, name))).collect(toList());
-    return new HalRepresentation(createLinks(namespace, name), embedDtos(dtos));
+    return new HalRepresentation(createLinks(namespace, name), embedDtos(getBranchDtoList(namespace, name, branches)));
+  }
+
+  public List<BranchDto> getBranchDtoList(String namespace, String name, Collection<Branch> branches) {
+    return branches.stream().map(branch -> branchToDtoMapper.map(branch, new NamespaceAndName(namespace, name))).collect(toList());
   }
 
   private Links createLinks(String namespace, String name) {

scm-webapp/src/main/java/sonia/scm/api/v2/resources/ChangesetCollectionToDtoMapper.java

@@ -0,0 +1,42 @@
+package sonia.scm.api.v2.resources;
+
+import sonia.scm.PageResult;
+import sonia.scm.repository.Changeset;
+import sonia.scm.repository.Repository;
+
+import javax.inject.Inject;
+
+public class ChangesetCollectionToDtoMapper extends BasicCollectionToDtoMapper<Changeset, ChangesetDto, ChangesetToChangesetDtoMapper> {
+
+  private final ResourceLinks resourceLinks;
+
+  @Inject
+  public ChangesetCollectionToDtoMapper(ChangesetToChangesetDtoMapper changesetToChangesetDtoMapper, ResourceLinks resourceLinks) {
+    super("changesets", changesetToChangesetDtoMapper);
+    this.resourceLinks = resourceLinks;
+  }
+
+  public CollectionDto map(int pageNumber, int pageSize, PageResult<Changeset> pageResult, Repository repository) {
+    return super.map(pageNumber, pageSize, pageResult, changeset -> super.entityToDtoMapper.map(changeset, repository), createSelfLink(repository));
+  }
+
+
+  @Override
+  String createCreateLink() {
+    return null;
+  }
+
+  @Override
+  String createSelfLink() {
+    return null;
+  }
+
+  private String createSelfLink(Repository repository) {
+    return resourceLinks.changeset().all(repository.getNamespace(), repository.getName());
+  }
+
+  @Override
+  boolean isCreatePermitted() {
+    return false;
+  }
+}

scm-webapp/src/main/java/sonia/scm/api/v2/resources/ChangesetDto.java

@@ -0,0 +1,49 @@
+package sonia.scm.api.v2.resources;
+
+import de.otto.edison.hal.HalRepresentation;
+import de.otto.edison.hal.Links;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+import java.time.Instant;
+import java.util.List;
+
+@Getter
+@Setter
+@NoArgsConstructor
+public class ChangesetDto extends HalRepresentation {
+
+  /**
+   * The changeset identification string
+   */
+  private String id;
+
+  /**
+   * The author of the changeset
+   */
+  private PersonDto author;
+
+  /**
+   * The date when the changeset was committed
+   */
+  private Instant date;
+
+  /**
+   * The text of the changeset description
+   */
+  private String description;
+
+  @Override
+  @SuppressWarnings("squid:S1185") // We want to have this method available in this package
+  protected HalRepresentation add(Links links) {
+    return super.add(links);
+  }
+
+  @SuppressWarnings("squid:S1185") // We want to have this method available in this package
+  protected HalRepresentation withEmbedded(String rel, List<? extends HalRepresentation> halRepresentations) {
+    return super.withEmbedded(rel, halRepresentations);
+  }
+
+
+}

scm-webapp/src/main/java/sonia/scm/api/v2/resources/ChangesetRootResource.java

@@ -1,25 +1,84 @@
 package sonia.scm.api.v2.resources;
 
+import com.webcohesion.enunciate.metadata.rs.ResponseCode;
+import com.webcohesion.enunciate.metadata.rs.StatusCodes;
+import com.webcohesion.enunciate.metadata.rs.TypeHint;
+import lombok.extern.slf4j.Slf4j;
+import sonia.scm.PageResult;
+import sonia.scm.repository.Changeset;
+import sonia.scm.repository.ChangesetPagingResult;
+import sonia.scm.repository.NamespaceAndName;
+import sonia.scm.repository.Repository;
+import sonia.scm.repository.RepositoryException;
+import sonia.scm.repository.RepositoryNotFoundException;
+import sonia.scm.repository.api.RepositoryService;
+import sonia.scm.repository.api.RepositoryServiceFactory;
+import sonia.scm.web.VndMediaType;
+
+import javax.inject.Inject;
 import javax.ws.rs.DefaultValue;
 import javax.ws.rs.GET;
 import javax.ws.rs.Path;
+import javax.ws.rs.PathParam;
+import javax.ws.rs.Produces;
 import javax.ws.rs.QueryParam;
 import javax.ws.rs.core.Response;
+import java.io.IOException;
 
+
+@Slf4j
 public class ChangesetRootResource {
 
+  private final RepositoryServiceFactory serviceFactory;
+
+  private final ChangesetCollectionToDtoMapper changesetCollectionToDtoMapper;
+
+  @Inject
+  public ChangesetRootResource(RepositoryServiceFactory serviceFactory, ChangesetCollectionToDtoMapper changesetCollectionToDtoMapper) {
+    this.serviceFactory = serviceFactory;
+    this.changesetCollectionToDtoMapper = changesetCollectionToDtoMapper;
+  }
+
   @GET
   @Path("")
-  public Response getAll(@DefaultValue("0") @QueryParam("page") int page,
-    @DefaultValue("10") @QueryParam("pageSize") int pageSize,
-    @QueryParam("sortBy") String sortBy,
-    @DefaultValue("false") @QueryParam("desc") boolean desc) {
-    throw new UnsupportedOperationException();
+  @StatusCodes({
+    @ResponseCode(code = 200, condition = "success"),
+    @ResponseCode(code = 401, condition = "not authenticated / invalid credentials"),
+    @ResponseCode(code = 403, condition = "not authorized, the current user has no privileges to read the changeset"),
+    @ResponseCode(code = 404, condition = "not found, no changeset with the specified name available in the repository"),
+    @ResponseCode(code = 500, condition = "internal server error")
+  })
+  @Produces(VndMediaType.CHANGESET_COLLECTION)
+  @TypeHint(CollectionDto.class)
+  public Response getAll(@PathParam("namespace") String namespace, @PathParam("name") String name, @DefaultValue("0") @QueryParam("page") int page,
+                         @DefaultValue("10") @QueryParam("pageSize") int pageSize) {
+    try (RepositoryService repositoryService = serviceFactory.create(new NamespaceAndName(namespace, name))) {
+      ChangesetPagingResult changesets;
+      Repository repository = repositoryService.getRepository();
+      changesets = repositoryService.getLogCommand()
+        .setPagingStart(page)
+        .setPagingLimit(pageSize)
+        .getChangesets();
+      if (changesets != null) {
+        PageResult<Changeset> pageResult = new PageResult<>(changesets.getChangesets(), changesets.getTotal());
+        return Response.ok(changesetCollectionToDtoMapper.map(page, pageSize, pageResult, repository)).build();
+      } else {
+        return Response.ok().build();
+      }
+    } catch (RepositoryNotFoundException e) {
+      log.debug("Not found in repository {}/{}", namespace, name, e);
+      return Response.status(Response.Status.NOT_FOUND).build();
+    } catch (RepositoryException e) {
+      e.printStackTrace();
+    } catch (IOException e) {
+      e.printStackTrace();
+    }
+    return Response.ok().build();
   }
 
   @GET
-  @Path("{revision}")
-  public Response get() {
+  @Path("{id}")
+  public Response get(@PathParam("id") String id) {
     throw new UnsupportedOperationException();
   }
 }

scm-webapp/src/main/java/sonia/scm/api/v2/resources/ChangesetToChangesetDtoMapper.java

@@ -0,0 +1,78 @@
+package sonia.scm.api.v2.resources;
+
+import de.otto.edison.hal.Links;
+import org.mapstruct.AfterMapping;
+import org.mapstruct.Context;
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+import org.mapstruct.MappingTarget;
+import sonia.scm.repository.Branch;
+import sonia.scm.repository.Changeset;
+import sonia.scm.repository.Repository;
+import sonia.scm.repository.Tag;
+import sonia.scm.repository.api.Command;
+import sonia.scm.repository.api.RepositoryService;
+import sonia.scm.repository.api.RepositoryServiceFactory;
+
+import javax.inject.Inject;
+import java.util.List;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
+import static de.otto.edison.hal.Link.link;
+import static de.otto.edison.hal.Links.linkingTo;
+
+@Mapper
+public abstract class ChangesetToChangesetDtoMapper extends BaseMapper<Changeset, ChangesetDto> {
+
+  @Inject
+  private RepositoryServiceFactory serviceFactory;
+
+  @Inject
+  private ResourceLinks resourceLinks;
+
+
+  @Inject
+  private BranchCollectionToDtoMapper branchCollectionToDtoMapper;
+
+  @Inject
+  private ChangesetToParentDtoMapper changesetToParentDtoMapper;
+
+  @Inject
+  private TagCollectionToDtoMapper tagCollectionToDtoMapper;
+
+
+  @Mapping(target = "attributes", ignore = true) // We do not map HAL attributes
+  public abstract ChangesetDto map(Changeset changeset, @Context Repository repository);
+
+
+  @AfterMapping
+  void appendLinks(Changeset source, @MappingTarget ChangesetDto target, @Context Repository repository) {
+    String namespace = repository.getNamespace();
+    String name = repository.getName();
+
+    try (RepositoryService repositoryService = serviceFactory.create(repository)) {
+      if (repositoryService.isSupported(Command.TAGS)) {
+        target.withEmbedded("tags", tagCollectionToDtoMapper.getTagDtoList(namespace, name,
+          getListOfObjects(source.getTags(), tagName -> new Tag(tagName, source.getId()))));
+      }
+      if (repositoryService.isSupported(Command.BRANCHES)) {
+        target.withEmbedded("branches", branchCollectionToDtoMapper.getBranchDtoList(namespace, name,
+          getListOfObjects(source.getBranches(), branchName -> new Branch(branchName, source.getId()))));
+      }
+    }
+    target.withEmbedded("parents", getListOfObjects(source.getParents(), parent -> changesetToParentDtoMapper.map(new Changeset(parent, 0L, null), repository)));
+
+    Links.Builder linksBuilder = linkingTo()
+      .self(resourceLinks.changeset().self(repository.getNamespace(), repository.getName(), target.getId()))
+      .single(link("diff", resourceLinks.diff().self(namespace, name, target.getId())));
+    target.add(linksBuilder.build());
+  }
+
+  private <T> List<T> getListOfObjects(List<String> list, Function<String, T> mapFunction) {
+    return list
+      .stream()
+      .map(mapFunction)
+      .collect(Collectors.toList());
+  }
+}

scm-webapp/src/main/java/sonia/scm/api/v2/resources/ChangesetToParentDtoMapper.java

@@ -0,0 +1,38 @@
+package sonia.scm.api.v2.resources;
+
+
+import de.otto.edison.hal.Links;
+import org.mapstruct.AfterMapping;
+import org.mapstruct.Context;
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+import org.mapstruct.MappingTarget;
+import sonia.scm.repository.Changeset;
+import sonia.scm.repository.Repository;
+
+import javax.inject.Inject;
+
+import static de.otto.edison.hal.Link.link;
+import static de.otto.edison.hal.Links.linkingTo;
+
+@Mapper
+public abstract class ChangesetToParentDtoMapper extends BaseMapper<Changeset, ParentChangesetDto> {
+
+  @Inject
+  private ResourceLinks resourceLinks;
+
+  @Mapping(target = "attributes", ignore = true) // We do not map HAL attributes
+  public abstract ParentChangesetDto map(Changeset changeset, @Context Repository repository);
+
+
+  @AfterMapping
+  void appendLinks(@MappingTarget ParentChangesetDto target, @Context Repository repository) {
+    String namespace = repository.getNamespace();
+    String name = repository.getName();
+    Links.Builder linksBuilder = linkingTo()
+      .self(resourceLinks.changeset().self(repository.getNamespace(), repository.getName(), target.getId()))
+      .single(link("diff", resourceLinks.diff().self(namespace, name, target.getId())));
+    target.add(linksBuilder.build());
+  }
+
+}

scm-webapp/src/main/java/sonia/scm/api/v2/resources/DiffRootResource.java

@@ -0,0 +1,27 @@
+package sonia.scm.api.v2.resources;
+
+import javax.ws.rs.DefaultValue;
+import javax.ws.rs.GET;
+import javax.ws.rs.Path;
+import javax.ws.rs.QueryParam;
+import javax.ws.rs.core.Response;
+
+public class DiffRootResource {
+
+
+  @GET
+  @Path("")
+  public Response getAll(@DefaultValue("0") @QueryParam("page") int page,
+                         @DefaultValue("10") @QueryParam("pageSize") int pageSize,
+                         @QueryParam("sortBy") String sortBy,
+                         @DefaultValue("false") @QueryParam("desc") boolean desc) {
+    throw new UnsupportedOperationException();
+  }
+
+  @GET
+  @Path("{id}")
+  public Response get(String id) {
+    throw new UnsupportedOperationException();
+  }
+
+}

scm-webapp/src/main/java/sonia/scm/api/v2/resources/GroupCollectionToDtoMapper.java

@@ -5,7 +5,7 @@ import sonia.scm.group.GroupPermissions;
 
 import javax.inject.Inject;
 
-public class GroupCollectionToDtoMapper extends BasicCollectionToDtoMapper<Group, GroupDto> {
+public class GroupCollectionToDtoMapper extends BasicCollectionToDtoMapper<Group, GroupDto, GroupToGroupDtoMapper> {
 
   private final ResourceLinks resourceLinks;
 

scm-webapp/src/main/java/sonia/scm/api/v2/resources/MapperModule.java

@@ -28,6 +28,11 @@ public class MapperModule extends AbstractModule {
     bind(PermissionDtoToPermissionMapper.class).to(Mappers.getMapper(PermissionDtoToPermissionMapper.class).getClass());
     bind(PermissionToPermissionDtoMapper.class).to(Mappers.getMapper(PermissionToPermissionDtoMapper.class).getClass());
 
+    bind(ChangesetToChangesetDtoMapper.class).to(Mappers.getMapper(ChangesetToChangesetDtoMapper.class).getClass());
+    bind(ChangesetToParentDtoMapper.class).to(Mappers.getMapper(ChangesetToParentDtoMapper.class).getClass());
+
+    bind(TagToTagDtoMapper.class).to(Mappers.getMapper(TagToTagDtoMapper.class).getClass());
+
     bind(UriInfoStore.class).in(ServletScopes.REQUEST);
   }
 }

scm-webapp/src/main/java/sonia/scm/api/v2/resources/ParentChangesetDto.java

@@ -0,0 +1,27 @@
+package sonia.scm.api.v2.resources;
+
+import de.otto.edison.hal.HalRepresentation;
+import de.otto.edison.hal.Links;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import lombok.ToString;
+
+@Getter
+@Setter
+@ToString
+@NoArgsConstructor
+public class ParentChangesetDto extends HalRepresentation {
+
+  /**
+   * the id of the parent changeset
+   */
+  private String id;
+
+  @Override
+  @SuppressWarnings("squid:S1185") // We want to have this method available in this package
+  protected HalRepresentation add(Links links) {
+    return super.add(links);
+  }
+
+}

scm-webapp/src/main/java/sonia/scm/api/v2/resources/PersonDto.java

@@ -0,0 +1,22 @@
+package sonia.scm.api.v2.resources;
+
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@Getter
+@Setter
+@NoArgsConstructor
+public class PersonDto {
+
+  /**
+   * mail address of the person
+   */
+  private String mail;
+
+  /**
+   * name of the person
+   */
+  private String name;
+
+}

scm-webapp/src/main/java/sonia/scm/api/v2/resources/RepositoryCollectionToDtoMapper.java

@@ -7,7 +7,7 @@ import javax.inject.Inject;
 
 // Mapstruct does not support parameterized (i.e. non-default) constructors. Thus, we need to use field injection.
 @SuppressWarnings("squid:S3306")
-public class RepositoryCollectionToDtoMapper extends BasicCollectionToDtoMapper<Repository, RepositoryDto> {
+public class RepositoryCollectionToDtoMapper extends BasicCollectionToDtoMapper<Repository, RepositoryDto, RepositoryToRepositoryDtoMapper> {
 
   private final ResourceLinks resourceLinks;
 

scm-webapp/src/main/java/sonia/scm/api/v2/resources/RepositoryToRepositoryDtoMapper.java

@@ -40,13 +40,13 @@ public abstract class RepositoryToRepositoryDtoMapper extends BaseMapper<Reposit
     }
     try (RepositoryService repositoryService = serviceFactory.create(repository)) {
       if (repositoryService.isSupported(Command.TAGS)) {
-        linksBuilder.single(link("tags", resourceLinks.tagCollection().self(target.getNamespace(), target.getName())));
+        linksBuilder.single(link("tags", resourceLinks.tag().all(target.getNamespace(), target.getName())));
       }
       if (repositoryService.isSupported(Command.BRANCHES)) {
         linksBuilder.single(link("branches", resourceLinks.branchCollection().self(target.getNamespace(), target.getName())));
       }
     }
-    linksBuilder.single(link("changesets", resourceLinks.changeset().self(target.getNamespace(), target.getName())));
+    linksBuilder.single(link("changesets", resourceLinks.changeset().all(target.getNamespace(), target.getName())));
     linksBuilder.single(link("sources", resourceLinks.source().self(target.getNamespace(), target.getName())));
     target.add(linksBuilder.build());
   }

scm-webapp/src/main/java/sonia/scm/api/v2/resources/ResourceLinks.java

@@ -207,7 +207,7 @@ class ResourceLinks {
   }
 
 
-  public TagCollectionLinks tagCollection() {
+  public TagCollectionLinks tag() {
     return new TagCollectionLinks(uriInfoStore.get());
   }
 
@@ -215,11 +215,35 @@ class ResourceLinks {
     private final LinkBuilder tagLinkBuilder;
 
     TagCollectionLinks(UriInfo uriInfo) {
-      tagLinkBuilder = new LinkBuilder(uriInfo, RepositoryRootResource.class, RepositoryResource.class, TagRootResource.class, TagCollectionResource.class);
+      tagLinkBuilder = new LinkBuilder(uriInfo, RepositoryRootResource.class, RepositoryResource.class, TagRootResource.class);
     }
 
-    String self(String namespace, String name) {
-      return tagLinkBuilder.method("getRepositoryResource").parameters(namespace, name).method("tags").parameters().method("getTagCollectionResource").parameters().method("getAll").parameters().href();
+    String self(String namespace, String name, String id) {
+      return tagLinkBuilder.method("getRepositoryResource").parameters(namespace, name).method("tags").parameters().method("get").parameters(id).href();
+    }
+
+    String all(String namespace, String name) {
+      return tagLinkBuilder.method("getRepositoryResource").parameters(namespace, name).method("tags").parameters().method("getAll").parameters().href();
+    }
+  }
+
+  public DiffLinks diff() {
+    return new DiffLinks(uriInfoStore.get());
+  }
+
+  static class DiffLinks {
+    private final LinkBuilder diffLinkBuilder;
+
+    DiffLinks(UriInfo uriInfo) {
+      diffLinkBuilder = new LinkBuilder(uriInfo, RepositoryRootResource.class, RepositoryResource.class, DiffRootResource.class);
+    }
+
+    String self(String namespace, String name, String id) {
+      return diffLinkBuilder.method("getRepositoryResource").parameters(namespace, name).method("diff").parameters().method("get").parameters(id).href();
+    }
+
+    String all(String namespace, String name) {
+      return diffLinkBuilder.method("getRepositoryResource").parameters(namespace, name).method("diff").parameters().method("getAll").parameters().href();
     }
   }
 
@@ -270,7 +294,11 @@ class ResourceLinks {
       changesetLinkBuilder = new LinkBuilder(uriInfo, RepositoryRootResource.class, RepositoryResource.class, ChangesetRootResource.class);
     }
 
-    String self(String namespace, String name) {
+    String self(String namespace, String name, String changesetId) {
+      return changesetLinkBuilder.method("getRepositoryResource").parameters(namespace, name).method("changesets").parameters().method("get").parameters(changesetId).href();
+    }
+
+    String all(String namespace, String name) {
       return changesetLinkBuilder.method("getRepositoryResource").parameters(namespace, name).method("changesets").parameters().method("getAll").parameters().href();
     }
 

scm-webapp/src/main/java/sonia/scm/api/v2/resources/TagCollectionResource.java

@@ -1,18 +0,0 @@
-package sonia.scm.api.v2.resources;
-
-import javax.ws.rs.DefaultValue;
-import javax.ws.rs.GET;
-import javax.ws.rs.Path;
-import javax.ws.rs.QueryParam;
-import javax.ws.rs.core.Response;
-
-public class TagCollectionResource {
-  @GET
-  @Path("")
-  public Response getAll(@DefaultValue("0") @QueryParam("page") int page,
-    @DefaultValue("10") @QueryParam("pageSize") int pageSize,
-    @QueryParam("sortBy") String sortBy,
-    @DefaultValue("false") @QueryParam("desc") boolean desc) {
-    throw new UnsupportedOperationException();
-  }
-}

scm-webapp/src/main/java/sonia/scm/api/v2/resources/TagCollectionToDtoMapper.java

@@ -0,0 +1,49 @@
+package sonia.scm.api.v2.resources;
+
+import com.google.inject.Inject;
+import de.otto.edison.hal.Embedded;
+import de.otto.edison.hal.HalRepresentation;
+import de.otto.edison.hal.Links;
+import sonia.scm.repository.NamespaceAndName;
+import sonia.scm.repository.Tag;
+
+import java.util.Collection;
+import java.util.List;
+
+import static de.otto.edison.hal.Embedded.embeddedBuilder;
+import static de.otto.edison.hal.Links.linkingTo;
+import static java.util.stream.Collectors.toList;
+
+public class TagCollectionToDtoMapper {
+
+
+  private final ResourceLinks resourceLinks;
+  private final TagToTagDtoMapper tagToTagDtoMapper;
+
+  @Inject
+  public TagCollectionToDtoMapper(ResourceLinks resourceLinks, TagToTagDtoMapper tagToTagDtoMapper) {
+    this.resourceLinks = resourceLinks;
+    this.tagToTagDtoMapper = tagToTagDtoMapper;
+  }
+
+  public HalRepresentation map(String namespace, String name, Collection<Tag> tags) {
+    return new HalRepresentation(createLinks(namespace, name), embedDtos(getTagDtoList(namespace, name, tags)));
+  }
+
+  public List<TagDto> getTagDtoList(String namespace, String name, Collection<Tag> tags) {
+    return tags.stream().map(tag -> tagToTagDtoMapper.map(tag, new NamespaceAndName(namespace, name))).collect(toList());
+  }
+
+  private Links createLinks(String namespace, String name) {
+    return
+      linkingTo()
+        .self(resourceLinks.tag().all(namespace, name))
+        .build();
+  }
+
+  private Embedded embedDtos(List<TagDto> dtos) {
+    return embeddedBuilder()
+      .with("tags", dtos)
+      .build();
+  }
+}

scm-webapp/src/main/java/sonia/scm/api/v2/resources/TagDto.java

@@ -0,0 +1,24 @@
+package sonia.scm.api.v2.resources;
+
+import de.otto.edison.hal.HalRepresentation;
+import de.otto.edison.hal.Links;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@Getter
+@Setter
+@NoArgsConstructor
+public class TagDto extends HalRepresentation {
+
+  private String name;
+
+  private String revision;
+
+  @Override
+  @SuppressWarnings("squid:S1185") // We want to have this method available in this package
+  protected HalRepresentation add(Links links) {
+    return super.add(links);
+  }
+
+}

scm-webapp/src/main/java/sonia/scm/api/v2/resources/TagRootResource.java

@@ -1,20 +1,27 @@
 package sonia.scm.api.v2.resources;
 
-import javax.inject.Inject;
-import javax.inject.Provider;
+import javax.ws.rs.DefaultValue;
+import javax.ws.rs.GET;
 import javax.ws.rs.Path;
+import javax.ws.rs.QueryParam;
+import javax.ws.rs.core.Response;
 
 public class TagRootResource {
 
-  private final Provider<TagCollectionResource> tagCollectionResource;
-
-  @Inject
-  public TagRootResource(Provider<TagCollectionResource> tagCollectionResource) {
-    this.tagCollectionResource = tagCollectionResource;
-  }
 
+  @GET
   @Path("")
-  public TagCollectionResource getTagCollectionResource() {
-    return tagCollectionResource.get();
+  public Response getAll(@DefaultValue("0") @QueryParam("page") int page,
+                         @DefaultValue("10") @QueryParam("pageSize") int pageSize,
+                         @QueryParam("sortBy") String sortBy,
+                         @DefaultValue("false") @QueryParam("desc") boolean desc) {
+    throw new UnsupportedOperationException();
   }
+
+  @GET
+  @Path("{id}")
+  public Response get(String id) {
+    throw new UnsupportedOperationException();
+  }
+
 }

scm-webapp/src/main/java/sonia/scm/api/v2/resources/TagToTagDtoMapper.java

@@ -0,0 +1,31 @@
+package sonia.scm.api.v2.resources;
+
+import de.otto.edison.hal.Links;
+import org.mapstruct.AfterMapping;
+import org.mapstruct.Context;
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+import org.mapstruct.MappingTarget;
+import sonia.scm.repository.NamespaceAndName;
+import sonia.scm.repository.Tag;
+
+import javax.inject.Inject;
+
+import static de.otto.edison.hal.Links.linkingTo;
+
+@Mapper
+public abstract class TagToTagDtoMapper {
+
+  @Inject
+  private ResourceLinks resourceLinks;
+
+  @Mapping(target = "attributes", ignore = true) // We do not map HAL attributes
+  public abstract TagDto map(Tag tag, @Context NamespaceAndName namespaceAndName);
+
+  @AfterMapping
+  void appendLinks(@MappingTarget TagDto target, @Context NamespaceAndName namespaceAndName) {
+    Links.Builder linksBuilder = linkingTo()
+      .self(resourceLinks.tag().self(namespaceAndName.getNamespace(), namespaceAndName.getName(), target.getName()));
+    target.add(linksBuilder.build());
+  }
+}

scm-webapp/src/main/java/sonia/scm/api/v2/resources/UserCollectionToDtoMapper.java

@@ -7,7 +7,7 @@ import javax.inject.Inject;
 
 // Mapstruct does not support parameterized (i.e. non-default) constructors. Thus, we need to use field injection.
 @SuppressWarnings("squid:S3306")
-public class UserCollectionToDtoMapper extends BasicCollectionToDtoMapper<User, UserDto> {
+public class UserCollectionToDtoMapper extends BasicCollectionToDtoMapper<User, UserDto, UserToUserDtoMapper> {
 
   private final ResourceLinks resourceLinks;