Serve Git reads over SSH

Summary: Like D7423, but for SSH.

Test Plan: Ran `git clone ssh://...`, got a clone.

Reviewers: btrahan

Reviewed By: btrahan

CC: hach-que, aran

Maniphest Tasks: T2230

Differential Revision: https://secure.phabricator.com/D7424

src/applications/diffusion/ssh/DiffusionSSHGitUploadPackWorkflow.php

@@ -23,4 +23,12 @@ final class DiffusionSSHGitUploadPackWorkflow
     return head($args->getArg('dir'));
   }
 
+  protected function executeRepositoryOperations(
+    PhabricatorRepository $repository) {
+
+    $future = new ExecFuture('git-upload-pack %s', $repository->getLocalPath());
+
+    return $this->passthruIO($future);
+  }
+
 }

src/applications/diffusion/ssh/DiffusionSSHWorkflow.php

@@ -10,6 +10,9 @@ abstract class DiffusionSSHWorkflow extends PhabricatorSSHWorkflow {
 
   abstract protected function isReadOnly();
   abstract protected function getRequestPath();
+  abstract protected function executeRepositoryOperations(
+    PhabricatorRepository $repository);
+
   protected function writeError($message) {
     $this->getErrorChannel()->write($message);
     return $this;
@@ -20,15 +23,11 @@ abstract class DiffusionSSHWorkflow extends PhabricatorSSHWorkflow {
 
     try {
       $repository = $this->loadRepository();
-
-      throw new Exception("TODO: Implement serve over SSH.");
-
+      return $this->executeRepositoryOperations($repository);
     } catch (Exception $ex) {
       $this->writeError(get_class($ex).': '.$ex->getMessage());
       return 1;
     }
-
-    return 0;
   }
 
   private function loadRepository() {