Added support for searching for tags (#417).

src/main/java/org/gitlab4j/api/Constants.java

@@ -221,6 +221,28 @@ public interface Constants {
         }
     }
 
+    /** Enum to use for ordering the results of getTags(). */
+    public enum TagOrderBy {
+
+        NAME, UPDATED;
+        private static JacksonJsonEnumHelper<TagOrderBy> enumHelper = new JacksonJsonEnumHelper<>(TagOrderBy.class);
+
+        @JsonCreator
+        public static TagOrderBy forValue(String value) {
+            return enumHelper.forValue(value);
+        }
+
+        @JsonValue
+        public String toValue() {
+            return (enumHelper.toString(this));
+        }
+
+        @Override
+        public String toString() {
+            return (enumHelper.toString(this));
+        }
+    }
+
     /** Enum to use for specifying the scope when calling getPipelines(). */
     public enum PipelineScope {
 

src/main/java/org/gitlab4j/api/TagsApi.java

@@ -85,6 +85,89 @@ public class TagsApi extends AbstractApi {
         return (getTags(projectIdOrPath, getDefaultPerPage()).stream());
     }
 
+    /**
+     * Get a list of repository tags from a project, sorted by name in reverse alphabetical order.
+     *
+     * <pre><code>GitLab Endpoint: GET /projects/:id/repository/tags</code></pre>
+     *
+     * @param projectIdOrPath id, path of the project, or a Project instance holding the project ID or path
+     * @param orderBy return tags ordered by name or updated fields. Default is updated
+     * @param sortOrder return tags sorted in asc or desc order. Default is desc
+     * @param search return list of tags matching the search criteria
+     * @return the list of tags for the specified project ID
+     * @throws GitLabApiException if any exception occurs
+     * @since GitLab 11.8
+     */
+    public List<Tag> getTags(Object projectIdOrPath, TagOrderBy orderBy, SortOrder sortOrder, String search) throws GitLabApiException {
+        return (getTags(projectIdOrPath, orderBy, sortOrder, search, getDefaultPerPage()).all());
+    }
+
+    /**
+     * Get a list of repository tags from a project, sorted by name in reverse alphabetical order and in the specified page range.
+     *
+     * <pre><code>GitLab Endpoint: GET /projects/:id/repository/tags</code></pre>
+     *
+     * @param projectIdOrPath id, path of the project, or a Project instance holding the project ID or path
+     * @param orderBy return tags ordered by name or updated fields. Default is updated
+     * @param sortOrder return tags sorted in asc or desc order. Default is desc
+     * @param search return list of tags matching the search criteria
+     * @param page the page to get
+     * @param perPage the number of Tag instances per page
+     * @return the list of tags for the specified project ID
+     * @throws GitLabApiException if any exception occurs
+     * @since GitLab 11.8
+     */
+    public List<Tag> getTags(Object projectIdOrPath, TagOrderBy orderBy, SortOrder sortOrder, String search, int page, int perPage) throws GitLabApiException {
+        Form formData = new GitLabApiForm()
+                .withParam("order_by", orderBy)
+                .withParam("sort", sortOrder)
+                .withParam("search", search)
+                .withParam(PAGE_PARAM,  page)
+                .withParam(PER_PAGE_PARAM, perPage);
+        Response response = get(Response.Status.OK, formData.asMap(),
+                "projects", getProjectIdOrPath(projectIdOrPath), "repository", "tags");
+        return (response.readEntity(new GenericType<List<Tag>>() { }));
+    }
+
+    /**
+     * Get a list of repository tags from a project, sorted by name in reverse alphabetical order.
+     *
+     * <pre><code>GitLab Endpoint: GET /projects/:id/repository/tags</code></pre>
+     *
+     * @param projectIdOrPath id, path of the project, or a Project instance holding the project ID or path
+     * @param orderBy return tags ordered by name or updated fields. Default is updated
+     * @param sortOrder return tags sorted in asc or desc order. Default is desc
+     * @param search return list of tags matching the search criteria
+     * @param itemsPerPage the number of Project instances that will be fetched per page
+     * @return the Pager of tags for the specified project ID
+     * @throws GitLabApiException if any exception occurs
+     * @since GitLab 11.8
+     */
+    public Pager<Tag> getTags(Object projectIdOrPath, TagOrderBy orderBy, SortOrder sortOrder, String search, int itemsPerPage) throws GitLabApiException {
+        Form formData = new GitLabApiForm()
+                .withParam("order_by", orderBy)
+                .withParam("sort", sortOrder)
+                .withParam("search", search);
+        return (new Pager<Tag>(this, Tag.class, itemsPerPage, formData.asMap(), "projects", getProjectIdOrPath(projectIdOrPath), "repository", "tags"));
+    }
+
+    /**
+     * Get a Stream of repository tags from a project, sorted by name in reverse alphabetical order.
+     *
+     * <pre><code>GitLab Endpoint: GET /projects/:id/repository/tags</code></pre>
+     *
+     * @param projectIdOrPath id, path of the project, or a Project instance holding the project ID or path
+     * @param orderBy return tags ordered by name or updated fields. Default is updated
+     * @param sortOrder return tags sorted in asc or desc order. Default is desc
+     * @param search return list of tags matching the search criteria
+     * @return a Stream of tags for the specified project ID
+     * @throws GitLabApiException if any exception occurs
+     * @since GitLab 11.8
+     */
+    public Stream<Tag> getTagsStream(Object projectIdOrPath, TagOrderBy orderBy, SortOrder sortOrder, String search) throws GitLabApiException {
+        return (getTags(projectIdOrPath, orderBy, sortOrder, search, getDefaultPerPage()).stream());
+    }
+
     /**
      * Get a specific repository tag determined by its name.
      *

src/test/java/org/gitlab4j/api/TestTagsApi.java

 package org.gitlab4j.api;
 
+import static org.hamcrest.CoreMatchers.nullValue;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
@@ -9,6 +10,7 @@ import static org.junit.Assume.assumeTrue;
 import java.util.List;
 import java.util.Optional;
 
+import org.gitlab4j.api.Constants.SortOrder;
 import org.gitlab4j.api.models.AccessLevel;
 import org.gitlab4j.api.models.Project;
 import org.gitlab4j.api.models.ProtectedTag;
@@ -158,6 +160,35 @@ public class TestTagsApi extends AbstractIntegrationTest {
         assertEquals(TEST_TAG_WITH_SLASH, testTag.getName());
     }
 
+    @Test
+    public void testGetTagsInAscOrder() throws GitLabApiException {
+        List<Tag> tags = gitLabApi.getTagsApi().getTags(testProject, null, SortOrder.ASC, null);
+        assertNotNull(tags);
+        assertTrue(tags.size() > 1);
+        assertTrue(tags.get(0).getName().compareTo(tags.get(1).getName()) < 0);
+    }
+
+    @Test
+    public void testGetTagsInDescOrder() throws GitLabApiException {
+        List<Tag> tags = gitLabApi.getTagsApi().getTags(testProject, null, SortOrder.DESC, null);
+        assertNotNull(tags);
+        assertTrue(tags.size() > 1);
+        assertTrue(tags.get(0).getName().compareTo(tags.get(1).getName()) > 0);
+    }
+
+    @Test
+    public void testGetTagsSearch() throws GitLabApiException {
+        List<Tag> tags = gitLabApi.getTagsApi().getTags(testProject);
+        assertNotNull(tags);
+        assertTrue(tags.size() > 0);
+
+        String tagName = tags.get(0).getName();
+        tags = gitLabApi.getTagsApi().getTags(testProject, null, null, tagName);
+        assertNotNull(tags);
+        assertTrue(tags.size() > 0);
+        assertEquals(tagName, tags.get(0).getName());
+    }
+
     @Test
     public void  testProtectedTags() throws GitLabApiException {