Add serial pipeline manager

This is designed to handle the case where we want:

* The pipeline to be triggered by changes so results report back to
  the change.
* Triggered on change merged.
* Jobs with file matchers so that if a subsystem is changed, only the
  deployment job for that subsystem is run.
* Every change is processed in strict sequence.

This is designed to accomodate a deployment pipeline with the above
constraints.

The pipeline manager hierarchy is getting complicated; mark the base
class as abstract, and also move the shared-queue methods into an
intermediate abstract class.  These are shared by both serial and
dependent managers.

Change-Id: I3c5f3b2f6298292c5c25665923e3a10b07be5419

1 files changed, 48 insertions, 0 deletions

diff --git a/tests/fixtures/layouts/serial.yaml b/tests/fixtures/layouts/serial.yaml
new file mode 100644
index 000000000..5a744ce82
--- /dev/null
+++ b/tests/fixtures/layouts/serial.yaml
@@ -0,0 +1,48 @@
+- pipeline:
+    name: deploy
+    manager: serial
+    trigger:
+      gerrit:
+        - event: change-merged
+    post-review: True
+    success:
+      gerrit: {}
+    failure:
+      gerrit: {}
+
+- job:
+    name: base
+    parent: null
+    nodeset:
+      nodes:
+        - label: ubuntu-xenial
+          name: controller
+
+- job:
+    name: job1
+    run: playbooks/job1.yaml
+
+- job:
+    name: job2
+    run: playbooks/job2.yaml
+
+- project:
+    name: org/project
+    deploy:
+      jobs:
+        - job1
+        - job2
+
+- project:
+    name: org/project1
+    deploy:
+      queue: shared
+      jobs:
+        - job1
+
+- project:
+    name: org/project2
+    deploy:
+      queue: shared
+      jobs:
+        - job1