Git driver

This patch improves the existing git driver by adding
a refs watcher thread. This refs watcher looks at
refs added, deleted, updated and trigger a ref-updated
event.

When a refs is updated and that the related commits
from oldrev to newrev include a change on .zuul.yaml/zuul.yaml
or zuul.d/*.yaml then tenants including that ref is reconfigured.

Furthermore the patch includes a triggering model. Events are
sent to the scheduler so jobs can be attached to a pipeline for
running jobs.

Change-Id: I529660cb20d011f36814abe64f837945dd3f1f33

3 files changed, 39 insertions, 0 deletions

diff --git a/zuul/merger/client.py b/zuul/merger/client.py
index 2614e5887..c89a6fba8 100644
--- a/zuul/merger/client.py
+++ b/zuul/merger/client.py
@@ -131,6 +131,15 @@ class MergeClient(object):
         job = self.submitJob('merger:cat', data, None, precedence)
         return job
 
+    def getFilesChanges(self, connection_name, project_name, branch,
+                        tosha=None, precedence=zuul.model.PRECEDENCE_HIGH):
+        data = dict(connection=connection_name,
+                    project=project_name,
+                    branch=branch,
+                    tosha=tosha)
+        job = self.submitJob('merger:fileschanges', data, None, precedence)
+        return job
+
     def onBuildCompleted(self, job):
         data = getJobData(job)
         merged = data.get('merged', False)
diff --git a/zuul/merger/merger.py b/zuul/merger/merger.py
index 06ec4b2b9..bd4ca58ee 100644
--- a/zuul/merger/merger.py
+++ b/zuul/merger/merger.py
@@ -314,6 +314,18 @@ class Repo(object):
                             'utf-8')
         return ret
 
+    def getFilesChanges(self, branch, tosha=None):
+        repo = self.createRepoObject()
+        files = set()
+        head = repo.heads[branch].commit
+        files.update(set(head.stats.files.keys()))
+        if tosha:
+            for cmt in head.iter_parents():
+                if cmt.hexsha == tosha:
+                    break
+                files.update(set(cmt.stats.files.keys()))
+        return list(files)
+
     def deleteRemote(self, remote):
         repo = self.createRepoObject()
         repo.delete_remote(repo.remotes[remote])
@@ -581,3 +593,8 @@ class Merger(object):
     def getFiles(self, connection_name, project_name, branch, files, dirs=[]):
         repo = self.getRepo(connection_name, project_name)
         return repo.getFiles(files, dirs, branch=branch)
+
+    def getFilesChanges(self, connection_name, project_name, branch,
+                        tosha=None):
+        repo = self.getRepo(connection_name, project_name)
+        return repo.getFilesChanges(branch, tosha)
diff --git a/zuul/merger/server.py b/zuul/merger/server.py
index 576d41ed5..aa04fc206 100644
--- a/zuul/merger/server.py
+++ b/zuul/merger/server.py
@@ -81,6 +81,7 @@ class MergeServer(object):
         self.worker.registerFunction("merger:merge")
         self.worker.registerFunction("merger:cat")
         self.worker.registerFunction("merger:refstate")
+        self.worker.registerFunction("merger:fileschanges")
 
     def stop(self):
         self.log.debug("Stopping")
@@ -117,6 +118,9 @@ class MergeServer(object):
                     elif job.name == 'merger:refstate':
                         self.log.debug("Got refstate job: %s" % job.unique)
                         self.refstate(job)
+                    elif job.name == 'merger:fileschanges':
+                        self.log.debug("Got fileschanges job: %s" % job.unique)
+                        self.fileschanges(job)
                     else:
                         self.log.error("Unable to handle job %s" % job.name)
                         job.sendWorkFail()
@@ -158,3 +162,12 @@ class MergeServer(object):
         result = dict(updated=True,
                       files=files)
         job.sendWorkComplete(json.dumps(result))
+
+    def fileschanges(self, job):
+        args = json.loads(job.arguments)
+        self.merger.updateRepo(args['connection'], args['project'])
+        files = self.merger.getFilesChanges(
+            args['connection'], args['project'], args['branch'], args['tosha'])
+        result = dict(updated=True,
+                      files=files)
+        job.sendWorkComplete(json.dumps(result))