Create git_http_low_speed_limit / git_http_low_speed_time

Expose 2 new settings to zuul.conf allowing an operator better
control over them.  By default we set the speed limit to 1000 bytes
and speed time to 30 seconds.

Change-Id: I9da80fcfc312cbc12ea11ee7284eaec23adb97c9
Signed-off-by: Paul Belanger <pabelanger@redhat.com>

doc/source/admin/components.rst

@@ -265,6 +265,22 @@ The following section of ``zuul.conf`` is used by the merger:
 
       Directory in which Zuul should clone git repositories.
 
+   .. attr:: git_http_low_speed_limit
+      :default: 1000
+
+      If the HTTP transfer speed is less then git_http_low_speed_limit for
+      longer then git_http_low_speed_time, the transfer is aborted.
+
+      Value in bytes, setting to 0 will disable.
+
+   .. attr:: git_http_low_speed_time
+      :default: 30
+
+      If the HTTP transfer speed is less then git_http_low_speed_limit for
+      longer then git_http_low_speed_time, the transfer is aborted.
+
+      Value in seconds, setting to 0 will disable.
+
    .. attr:: git_user_email
 
       Value to pass to `git config user.email

tests/unit/test_merger_repo.py

@@ -49,7 +49,7 @@ class TestMergerRepo(ZuulTestCase):
             msg='.git file in submodule should be a file')
 
         work_repo = Repo(parent_path, self.workspace_root,
-                         'none@example.org', 'User Name')
+                         'none@example.org', 'User Name', '0', '0')
         self.assertTrue(
             os.path.isdir(os.path.join(self.workspace_root, 'subdir')),
             msg='Cloned repository has a submodule placeholder directory')
@@ -60,7 +60,7 @@ class TestMergerRepo(ZuulTestCase):
         sub_repo = Repo(
             os.path.join(self.upstream_root, 'org/project2'),
             os.path.join(self.workspace_root, 'subdir'),
-            'none@example.org', 'User Name')
+            'none@example.org', 'User Name', '0', '0')
         self.assertTrue(os.path.exists(
             os.path.join(self.workspace_root, 'subdir', '.git')),
             msg='Cloned over the submodule placeholder')

zuul/executor/server.py

@@ -562,6 +562,10 @@ class ExecutorServer(object):
                                                   'disk_limit_per_job', 250))
         self.merge_email = get_default(self.config, 'merger', 'git_user_email')
         self.merge_name = get_default(self.config, 'merger', 'git_user_name')
+        self.merge_speed_limit = get_default(
+            config, 'merger', 'git_http_low_speed_limit', '1000')
+        self.merge_speed_time = get_default(
+            config, 'merger', 'git_http_low_speed_time', '30')
         execution_wrapper_name = get_default(self.config, 'executor',
                                              'execution_wrapper', 'bubblewrap')
         load_multiplier = float(get_default(self.config, 'executor',
@@ -618,9 +622,9 @@ class ExecutorServer(object):
             cache_root = self.merge_root
         else:
             cache_root = None
-        return zuul.merger.merger.Merger(root, self.connections,
+        return zuul.merger.merger.Merger(
-                                         self.merge_email, self.merge_name,
+            root, self.connections, self.merge_email, self.merge_name,
-                                         cache_root, logger)
+            self.merge_speed_limit, self.merge_speed_time, cache_root, logger)
 
     def start(self):
         self._running = True

zuul/merger/merger.py

@@ -44,16 +44,15 @@ class ZuulReference(git.Reference):
 
 
 class Repo(object):
-    def __init__(self, remote, local, email, username, sshkey=None,
+    def __init__(self, remote, local, email, username, speed_limit, speed_time,
-                 cache_path=None, logger=None):
+                 sshkey=None, cache_path=None, logger=None):
         if logger is None:
             self.log = logging.getLogger("zuul.Repo")
         else:
             self.log = logger
-        # TODO(pabelanger): Expose to user via zuul.conf.
         self.env = {
-            'GIT_HTTP_LOW_SPEED_LIMIT': '1000',
+            'GIT_HTTP_LOW_SPEED_LIMIT': speed_limit,
-            'GIT_HTTP_LOW_SPEED_TIME': '30',
+            'GIT_HTTP_LOW_SPEED_TIME': speed_time,
         }
         if sshkey:
             self.env['GIT_SSH_COMMAND'] = 'ssh -i %s' % (sshkey,)
@@ -297,7 +296,7 @@ class Repo(object):
 
 class Merger(object):
     def __init__(self, working_root, connections, email, username,
-                 cache_root=None, logger=None):
+                 speed_limit, speed_time, cache_root=None, logger=None):
         self.logger = logger
         if logger is None:
             self.log = logging.getLogger("zuul.Merger")
@@ -310,6 +309,8 @@ class Merger(object):
         self.connections = connections
         self.email = email
         self.username = username
+        self.speed_limit = speed_limit
+        self.speed_time = speed_time
         self.cache_root = cache_root
 
     def _addProject(self, hostname, project_name, url, sshkey):
@@ -322,8 +323,9 @@ class Merger(object):
                                           project_name)
             else:
                 cache_path = None
-            repo = Repo(url, path, self.email, self.username,
+            repo = Repo(
-                        sshkey, cache_path, self.logger)
+                url, path, self.email, self.username, self.speed_limit,
+                self.speed_time, sshkey, cache_path, self.logger)
 
             self.repos[key] = repo
         except Exception:

zuul/merger/server.py

@@ -33,9 +33,13 @@ class MergeServer(object):
                                  '/var/lib/zuul/merger-git')
         merge_email = get_default(self.config, 'merger', 'git_user_email')
         merge_name = get_default(self.config, 'merger', 'git_user_name')
-
+        speed_limit = get_default(
-        self.merger = merger.Merger(merge_root, connections, merge_email,
+            config, 'merger', 'git_http_low_speed_limit', '1000')
-                                    merge_name)
+        speed_time = get_default(
+            config, 'merger', 'git_http_low_speed_time', '30')
+        self.merger = merger.Merger(
+            merge_root, connections, merge_email, merge_name, speed_limit,
+            speed_time)
 
     def start(self):
         self._running = True