Implement as controller instead of filter

src/main/scala/ScalatraBootstrap.scala

@@ -25,10 +25,9 @@ class ScalatraBootstrap extends LifeCycle with SystemSettingsService {
     context.getFilterRegistration("gitAuthenticationFilter").addMappingForUrlPatterns(EnumSet.allOf(classOf[DispatcherType]), true, "/git/*")
     context.addFilter("apiAuthenticationFilter", new ApiAuthenticationFilter)
     context.getFilterRegistration("apiAuthenticationFilter").addMappingForUrlPatterns(EnumSet.allOf(classOf[DispatcherType]), true, "/api/v3/*")
-    context.addFilter("ghCompatRepositoryAccessFilter", new GHCompatRepositoryAccessFilter)
-    context.getFilterRegistration("ghCompatRepositoryAccessFilter").addMappingForUrlPatterns(EnumSet.allOf(classOf[DispatcherType]), true, "/*")
 
     // Register controllers
+    context.mount(new GitHubCompatibleAccessController, "/*")
     context.mount(new AnonymousAccessController, "/*")
 
     context.addFilter("pluginControllerFilter", new PluginControllerFilter)

src/main/scala/gitbucket/core/controller/GitHubCompatibleAccessController.scala

@@ -0,0 +1,29 @@
+package gitbucket.core.controller
+
+import org.scalatra.MovedPermanently
+
+class GitHubCompatibleAccessController extends GitHubCompatibleAccessControllerBase
+
+/**
+  * Provides GitHub compatible URLs for Git client.
+  *
+  * <ul>
+  *   <li>git clone http://localhost:8080/owner/repo</li>
+  *   <li>git clone http://localhost:8080/owner/repo.git</li>
+  * </ul>
+  */
+trait GitHubCompatibleAccessControllerBase extends ControllerBase {
+  /**
+    * Git client initiates a connection with /info/refs
+    *
+    * @see https://git-scm.com/book/en/v2/Git-Internals-Transfer-Protocols
+    */
+  get("/*/*/info/refs") {
+    redirectToGitServlet()
+  }
+
+  private def redirectToGitServlet(): Unit = {
+    val query = Option(request.getQueryString).map("?" + _).getOrElse("")
+    halt(MovedPermanently(baseUrl + "/git" + request.getRequestURI + query))
+  }
+}

src/main/scala/gitbucket/core/servlet/GHCompatRepositoryAccessFilter.scala

@@ -1,36 +0,0 @@
-package gitbucket.core.servlet
-
-import javax.servlet._
-import javax.servlet.http.{HttpServletRequest, HttpServletResponse}
-
-import gitbucket.core.service.SystemSettingsService
-import gitbucket.core.util.Implicits._
-
-/**
-  * A controller to provide GitHub compatible URL for Git clients.
-  */
-class GHCompatRepositoryAccessFilter extends Filter with SystemSettingsService {
-
-  override def init(filterConfig: FilterConfig): Unit = {}
-
-  override def doFilter(req: ServletRequest, res: ServletResponse, chain: FilterChain): Unit = {
-    val request = req.asInstanceOf[HttpServletRequest]
-    request.paths match {
-      // baseUrl/repositoryOwner/repositoryName/info/refs
-      // baseUrl/repositoryOwner/repositoryName.git/info/refs
-      case Array(repositoryOwner, repositoryName, "info", "refs", _*) => redirectToGitServlet(req, res)
-
-      case _ => chain.doFilter(req, res)
-    }
-  }
-
-  private def redirectToGitServlet(req: ServletRequest, res: ServletResponse): Unit = {
-    val request = req.asInstanceOf[HttpServletRequest]
-    val response = res.asInstanceOf[HttpServletResponse]
-    val query = Option(request.getQueryString).map("?" + _).getOrElse("")
-    response.sendRedirect(baseUrl(request) + "/git" + request.getRequestURI + query)
-  }
-
-  override def destroy(): Unit = {}
-
-}