Add a couple of new methods in NewBaseRepositoryImpl, update Gitlab connector accordingly

plugins/tasks/tasks-core/src/com/intellij/tasks/gitlab/GitlabRepository.java

@@ -134,7 +134,7 @@ public class GitlabRepository extends NewBaseRepositoryImpl {
 
   @NotNull
   List<GitlabProject> fetchProjects() throws Exception {
-    HttpGet request = new HttpGet(getRestApiBaseUrl() + "projects");
+    HttpGet request = new HttpGet(getRestApiUrl("projects"));
     ResponseHandler<List<GitlabProject>> handler = new GsonMultipleObjectsDeserializer<GitlabProject>(GSON, LIST_OF_PROJECTS_TYPE);
     return getHttpClient().execute(request, handler);
   }
@@ -142,7 +142,7 @@ public class GitlabRepository extends NewBaseRepositoryImpl {
   @SuppressWarnings("UnusedDeclaration")
   @NotNull
   GitlabProject fetchProject(int id) throws Exception {
-    HttpGet request = new HttpGet(getRestApiBaseUrl() + "project/" + id);
+    HttpGet request = new HttpGet(getRestApiUrl("project", id));
     return getHttpClient().execute(request, new GsonSingleObjectDeserializer<GitlabProject>(GSON, GitlabProject.class));
   }
 
@@ -154,14 +154,14 @@ public class GitlabRepository extends NewBaseRepositoryImpl {
 
   private String getIssuesUrl() {
     if (myCurrentProject != null && myCurrentProject != UNSPECIFIED_PROJECT) {
-      return getRestApiBaseUrl() + "projects/" + myCurrentProject.getId() + "/issues";
+      return getRestApiUrl("projects", myCurrentProject.getId(), "issues");
     }
-    return getRestApiBaseUrl() + "issues";
+    return getRestApiUrl("issues");
   }
 
   @NotNull
   GitlabIssue fetchIssue(int id) throws Exception {
-    HttpGet request = new HttpGet(getRestApiBaseUrl() + "issues/" + id);
+    HttpGet request = new HttpGet(getRestApiUrl("issues", id));
     ResponseHandler<GitlabIssue> handler = new GsonSingleObjectDeserializer<GitlabIssue>(GSON, GitlabIssue.class);
     return getHttpClient().execute(request, handler);
   }
@@ -171,8 +171,10 @@ public class GitlabRepository extends NewBaseRepositoryImpl {
     return super.isConfigured() && !myPassword.isEmpty();
   }
 
-  private String getRestApiBaseUrl() {
-    return getUrl() + REST_API_PATH_PREFIX;
+  @NotNull
+  @Override
+  public String getRestApiPathPrefix() {
+    return REST_API_PATH_PREFIX;
   }
 
   @Nullable

plugins/tasks/tasks-core/src/com/intellij/tasks/httpclient/NewBaseRepositoryImpl.java

@@ -4,6 +4,7 @@ import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.tasks.TaskRepositoryType;
 import com.intellij.tasks.config.TaskSettings;
 import com.intellij.tasks.impl.BaseRepository;
+import com.intellij.tasks.impl.TaskUtil;
 import com.intellij.util.net.CertificatesManager;
 import com.intellij.util.net.HttpConfigurable;
 import org.apache.http.HttpHost;
@@ -49,7 +50,7 @@ public abstract class NewBaseRepositoryImpl extends BaseRepository {
     HttpClientBuilder builder = HttpClients.custom()
       .setDefaultRequestConfig(createRequestConfig())
       .setSslcontext(CertificatesManager.getInstance().getSslContext())
-      // TODO: use custom one for additional certificate check
+        // TODO: use custom one for additional certificate check
       .setHostnameVerifier(SSLConnectionSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER)
       .setDefaultCredentialsProvider(createCredentialsProvider());
     HttpRequestInterceptor interceptor = createRequestInterceptor();
@@ -98,4 +99,40 @@ public abstract class NewBaseRepositoryImpl extends BaseRepository {
     }
     return builder.build();
   }
+
+  /**
+   * Return server's REST API path prefix, e.g. {@code /rest/api/latest} for JIRA or {@code /api/v3/} for Gitlab.
+   * This value will be used in {@link #getRestApiUrl(Object...)}
+   *
+   * @return server's REST API path prefix
+   */
+  @NotNull
+  public String getRestApiPathPrefix() {
+    return "";
+  }
+
+  /**
+   * Build URL using {@link #getUrl()}, {@link #getRestApiPathPrefix()}} and specified path components.
+   * <p/>
+   * Individual path components will should not contain leading or trailing slashes. Empty or null components
+   * will be omitted. Each components is converted to string using its {@link Object#toString()} method and url encoded, so
+   * numeric IDs can be used as well. Returned URL doesn't contain trailing '/', because it's not compatible with some services.
+   *
+   * @return described URL
+   */
+  @NotNull
+  public String getRestApiUrl(@NotNull Object... parts) {
+    StringBuilder builder = new StringBuilder(getUrl());
+    builder.append(getRestApiPathPrefix());
+    if (builder.charAt(builder.length() - 1) == '/') {
+      builder.deleteCharAt(builder.length() - 1);
+    }
+    for (Object part : parts) {
+      if (part == null || part.equals("")) {
+        continue;
+      }
+      builder.append('/').append(TaskUtil.encodeUrl(String.valueOf(part)));
+    }
+    return builder.toString();
+  }
 }

plugins/tasks/tasks-core/src/com/intellij/tasks/impl/TaskUtil.java

@@ -21,6 +21,7 @@ import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.util.Comparing;
 import com.intellij.openapi.util.JDOMUtil;
 import com.intellij.openapi.util.text.StringUtil;
+import com.intellij.openapi.vfs.CharsetToolkit;
 import com.intellij.tasks.Task;
 import com.intellij.tasks.TaskRepository;
 import org.jdom.Element;
@@ -28,7 +29,9 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.io.InputStream;
+import java.io.UnsupportedEncodingException;
 import java.lang.reflect.Type;
+import java.net.URLEncoder;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.Arrays;
@@ -220,4 +223,19 @@ public class TaskUtil {
   public static GsonBuilder installDateDeserializer(GsonBuilder builder) {
     return builder.registerTypeAdapter(Date.class, DATE_DESERIALIZER);
   }
+
+  /**
+   * Perform standard {@code application/x-www-urlencoded} translation for string {@code s}.
+   *
+   * @return urlencoded string
+   */
+  @NotNull
+  public static String encodeUrl(@NotNull String s) {
+    try {
+      return URLEncoder.encode(s, CharsetToolkit.UTF8);
+    }
+    catch (UnsupportedEncodingException e) {
+      throw new AssertionError("UTF-8 is not supported");
+    }
+  }
 }