[Findit] Add a sub-pipeline to detect first-known failure.

appengine/findit/model/build_analysis.py

Index: appengine/findit/model/build_analysis.py
diff --git a/appengine/findit/model/build_analysis.py b/appengine/findit/model/build_analysis.py
new file mode 100644
index 0000000000000000000000000000000000000000..aaba744bda12b2f1e88485921c1006d161d3a69e
--- /dev/null
+++ b/appengine/findit/model/build_analysis.py
@@ -0,0 +1,50 @@
+# Copyright (c) 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+from google.appengine.ext import ndb
+
+from model.build_analysis_status import BuildAnalysisStatus
+
+
+class BuildAnalysis(ndb.Model):
+  """Represent an analysis of a build cycle of a builder in a waterfall."""

[qyearsley, 2014/12/29 19:44:53]

As for functions, I think that verbs in docstrings for classes should also be in
third-person singular form -- "Represent" -> "Represents".

You can change this in build.py as well.

[stgao, 2015/01/03 01:31:47]

Done.

+
+  @staticmethod
+  def CreateKey(master_name, builder_name, build_number):  # pragma: no cover
+    return ndb.Key('Master', master_name, 'Builder', builder_name,
+                   'BuildAnalysis', build_number)
+
+  @staticmethod
+  def CreateBuildAnalysis(
+      master_name, builder_name, build_number):  # pragma: no cover
+    """Create a BuildAnalysis instance, but not save it to datastore."""

[qyearsley, 2014/12/29 19:44:53]

You can change this to:
"""Creates a BuildAnalysis instance, but does not save it to the datastore."""
Or, just remove it.

[stgao, 2015/01/03 01:31:47]

Done.

+    return BuildAnalysis(
+        key=BuildAnalysis.CreateKey(master_name, builder_name, build_number),
+        master_name=master_name,
+        builder_name=builder_name,
+        build_number=build_number)
+
+  @staticmethod
+  def GetBuildAnalysis(
+      master_name, builder_name, build_number):  # pragma: no cover
+    return BuildAnalysis.CreateKey(
+        master_name, builder_name, build_number).get()
+
+  def Reset(self):
+    """Reset to the state as if no analysis is run."""
+    self.status = BuildAnalysisStatus.PENDING
+    self.start_time = None
+    self.updated_time = None
+
+  # Information of the analyzed build.
+  master_name = ndb.StringProperty(indexed=False)
+  builder_name = ndb.StringProperty(indexed=False)
+  build_number = ndb.IntegerProperty(indexed=False)

[qyearsley, 2014/12/29 19:44:53]

Since master_name, builder_name and build_number are all already in the key,
it's unnecessary to store them separately -- you can use ndb.ComputedProperty,
and they'll be treated the same as any other property:

  @ndb.ComputedProperty
  def master_name(self):
    return self.key.parent().parent().id()

  @ndb.ComputedProperty
  def builder_name(self):
    return self.key.parent().id()

  @ndb.ComputedProperty
  def build_number(self):
    return self.key.id()

[stgao, 2015/01/03 01:31:47]

Good idea! I created a base class for this, because Build and BuildAnalysis
could share the code. Later, another two models Step/Test could share the code
too.

By "store them separately", I assume you meant setting them as separate fields
in the model, rather than storing them in the datastore. Computed properties
will be stored in datastore too.

+  build_start_time = ndb.DateTimeProperty(indexed=True)
+
+  # Information of analysis processing.
+  status = ndb.IntegerProperty(
+      default=BuildAnalysisStatus.PENDING, indexed=False)
+  start_time = ndb.DateTimeProperty(indexed=False)
+  updated_time = ndb.DateTimeProperty(indexed=False)