Store branch cache minimum ltimes in layout state

In order to check whether the project branch cache of a connection is
up-to-date we need store the cache ltimes as part of the layout state.

Change-Id: I3450dfd584d5b2c21f1c7171337054c137eed12d

tests/unit/test_github_driver.py

@@ -37,7 +37,7 @@ from tests.base import (AnsibleZuulTestCase, BaseTestCase,
                         simple_layout, random_sha1)
 from tests.base import ZuulWebFixture
 
-EMPTY_LAYOUT_STATE = LayoutState("", "", 0, None)
+EMPTY_LAYOUT_STATE = LayoutState("", "", 0, None, {})
 
 
 class TestGithubDriver(ZuulTestCase):

tests/unit/test_gitlab_driver.py

@@ -27,7 +27,7 @@ from tests.base import ZuulTestCase, ZuulWebFixture
 
 from testtools.matchers import MatchesRegex
 
-EMPTY_LAYOUT_STATE = LayoutState("", "", 0, None)
+EMPTY_LAYOUT_STATE = LayoutState("", "", 0, None, {})
 
 
 class TestGitlabWebhook(ZuulTestCase):

tests/unit/test_pagure_driver.py

@@ -27,7 +27,7 @@ from zuul.zk.layout import LayoutState
 from tests.base import ZuulTestCase, simple_layout
 from tests.base import ZuulWebFixture
 
-EMPTY_LAYOUT_STATE = LayoutState("", "", 0, None)
+EMPTY_LAYOUT_STATE = LayoutState("", "", 0, None, {})
 
 
 class TestPagureDriver(ZuulTestCase):

tests/unit/test_scheduler.py

@@ -51,7 +51,7 @@ from tests.base import (
 from zuul.zk.change_cache import ChangeKey
 from zuul.zk.layout import LayoutState
 
-EMPTY_LAYOUT_STATE = LayoutState("", "", 0, None)
+EMPTY_LAYOUT_STATE = LayoutState("", "", 0, None, {})
 
 
 class TestSchedulerSSL(SSLZuulTestCase):

tests/unit/test_zk.py

@@ -1164,16 +1164,25 @@ class TestLayoutStore(ZooKeeperBaseTestCase):
     def test_layout_state(self):
         store = LayoutStateStore(self.zk_client, lambda: None)
         layout_uuid = uuid.uuid4().hex
-        state = LayoutState("tenant", "hostname", 0, layout_uuid)
+        branch_cache_min_ltimes = {
+            "gerrit": 123,
+            "github": 456,
+        }
+        state = LayoutState("tenant", "hostname", 0, layout_uuid,
+                            branch_cache_min_ltimes)
         store["tenant"] = state
         self.assertEqual(state, store["tenant"])
         self.assertNotEqual(state.ltime, -1)
         self.assertNotEqual(store["tenant"].ltime, -1)
+        self.assertEqual(store["tenant"].branch_cache_min_ltimes,
+                         branch_cache_min_ltimes)
 
     def test_ordering(self):
         layout_uuid = uuid.uuid4().hex
-        state_one = LayoutState("tenant", "hostname", 1, layout_uuid, ltime=1)
-        state_two = LayoutState("tenant", "hostname", 2, layout_uuid, ltime=2)
+        state_one = LayoutState("tenant", "hostname", 1, layout_uuid,
+                                {}, ltime=1)
+        state_two = LayoutState("tenant", "hostname", 2, layout_uuid,
+                                {}, ltime=2)
 
         self.assertGreater(state_two, state_one)
 

zuul/scheduler.py

@@ -1329,11 +1329,19 @@ class Scheduler(threading.Thread):
             for reporter in pipeline.actions:
                 reporter.postConfig()
 
+        # Assemble a new list of min. ltimes of the project branch caches.
+        branch_cache_min_ltimes = {
+            s.connection.connection_name:
+                s.getProjectBranchCacheLtime()
+            for s in self.connections.getSources()
+        }
+
         layout_state = LayoutState(
             tenant_name=tenant.name,
             hostname=self.hostname,
             last_reconfigured=int(time.time()),
             uuid=tenant.layout.uuid,
+            branch_cache_min_ltimes=branch_cache_min_ltimes,
         )
         # We need to update the local layout state before the remote state,
         # to avoid race conditions in the layout changed callback.

zuul/zk/layout.py

@@ -44,12 +44,13 @@ class LayoutState:
     """
 
     def __init__(self, tenant_name, hostname, last_reconfigured, uuid,
-                 ltime=-1):
+                 branch_cache_min_ltimes, ltime=-1):
         self.uuid = uuid
         self.ltime = ltime
         self.tenant_name = tenant_name
         self.hostname = hostname
         self.last_reconfigured = last_reconfigured
+        self.branch_cache_min_ltimes = branch_cache_min_ltimes
 
     def toDict(self):
         return {
@@ -57,6 +58,7 @@ class LayoutState:
             "hostname": self.hostname,
             "last_reconfigured": self.last_reconfigured,
             "uuid": self.uuid,
+            "branch_cache_min_ltimes": self.branch_cache_min_ltimes,
         }
 
     @classmethod
@@ -66,6 +68,7 @@ class LayoutState:
             data["hostname"],
             data["last_reconfigured"],
             data.get("uuid"),
+            data.get("branch_cache_min_ltimes"),
             data.get("ltime", -1),
         )