Add retests/pr transform plugin.

velodrome/transform/BUILD

@@ -43,6 +43,7 @@ go_library(
         "plugins.go",
         "prstats.go",
         "rebase.go",
+        "retest.go",
         "transform.go",
     ],
     tags = ["automanaged"],

velodrome/transform/plugins.go

@@ -51,6 +51,7 @@ func NewPlugins(idb InfluxDatabase) Plugins {
 		NewLGTMToMergedPlugin(idb),
 		NewFirstCommentPlugin(idb),
 		NewRebasePlugin(idb),
+		NewRetestPlugin(idb),
 	}
 
 	return plugins

velodrome/transform/retest.go

@@ -0,0 +1,88 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"regexp"
+	"time"
+
+	"github.com/golang/glog"
+
+	"k8s.io/test-infra/velodrome/sql"
+)
+
+var (
+	// Matches "@k8s-bot foo bar test this" with the capture group "foo bar".
+	testThisRe = regexp.MustCompile(`@k8s-bot (\w*(?: \w+)*) ?test this`)
+
+	robotNames = map[string]bool{
+		"k8s-merge-robot": true,
+		"k8s-ci-robot":    true,
+	}
+)
+
+type Retest struct {
+	DB   InfluxDatabase
+	last time.Time
+	// Number of requests for retest per PR.
+	retests map[int]int
+}
+
+// NewRetestPlugin initializes the plugin.
+func NewRetestPlugin(DB InfluxDatabase) *Retest {
+	last, err := DB.GetLastMeasurement("retest")
+	if err != nil {
+		glog.Fatal("Failed to create Retest plugin: ", err)
+	}
+	return &Retest{
+		DB:      DB,
+		last:    last,
+		retests: make(map[int]int),
+	}
+}
+
+// ReceiveIssue is not used for this metric.
+func (*Retest) ReceiveIssue(sql.Issue) error {
+	return nil
+}
+
+// ReceiveComment counts occurences of "@k8s-bot test this"-style comments.
+func (r *Retest) ReceiveComment(comment sql.Comment) error {
+	if robotNames[comment.User] {
+		return nil
+	}
+	if matches := testThisRe.MatchString(comment.Body); !matches {
+		return nil
+	}
+	r.retests[comment.IssueID]++
+	return nil
+}
+
+// ReceiveIssueEvent adds to the DB when a PR is merged.
+func (r *Retest) ReceiveIssueEvent(event sql.IssueEvent) error {
+	if !event.EventCreatedAt.After(r.last) {
+		return nil
+	}
+	if event.Event != "merged" {
+		return nil
+	}
+	return r.DB.Push(
+		"retest",
+		nil,
+		map[string]interface{}{"value": r.retests[event.IssueId]},
+		event.EventCreatedAt)
+}