1 files changed, 150 insertions, 0 deletions
diff --git a/misc/dashboard/app/build/notify.go b/misc/dashboard/app/build/notify.go
new file mode 100644
index 000000000..826132be2
--- /dev/null
+++ b/misc/dashboard/app/build/notify.go
@@ -0,0 +1,150 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package build
+
+import (
+	"appengine"
+	"appengine/datastore"
+	"appengine/delay"
+	"appengine/mail"
+	"bytes"
+	"fmt"
+	"gob"
+	"os"
+	"template"
+)
+
+const (
+	mailFrom   = "builder@golang.org" // use this for sending any mail
+	failMailTo = "golang-dev@googlegroups.com"
+	domain     = "build.golang.org"
+)
+
+// notifyOnFailure checks whether the supplied Commit or the subsequent
+// Commit (if present) breaks the build for this builder.
+// If either of those commits break the build an email notification is sent
+// from a delayed task. (We use a task because this way the mail won't be
+// sent if the enclosing datastore transaction fails.)
+//
+// This must be run in a datastore transaction, and the provided *Commit must
+// have been retrieved from the datastore within that transaction.
+func notifyOnFailure(c appengine.Context, com *Commit, builder string) os.Error {
+	// TODO(adg): implement notifications for packages
+	if com.PackagePath != "" {
+		return nil
+	}
+
+	p := &Package{Path: com.PackagePath}
+	var broken *Commit
+	ok, present := com.OK(builder, "")
+	if !present {
+		return fmt.Errorf("no result for %s/%s", com.Hash, builder)
+	}
+	q := datastore.NewQuery("Commit").Ancestor(p.Key(c))
+	if ok {
+		// This commit is OK. Notify if next Commit is broken.
+		next := new(Commit)
+		q.Filter("ParentHash=", com.Hash)
+		if err := firstMatch(c, q, next); err != nil {
+			if err == datastore.ErrNoSuchEntity {
+				// OK at tip, no notification necessary.
+				return nil
+			}
+			return err
+		}
+		if ok, present := next.OK(builder, ""); present && !ok {
+			broken = next
+		}
+	} else {
+		// This commit is broken. Notify if the previous Commit is OK.
+		prev := new(Commit)
+		q.Filter("Hash=", com.ParentHash)
+		if err := firstMatch(c, q, prev); err != nil {
+			if err == datastore.ErrNoSuchEntity {
+				// No previous result, let the backfill of
+				// this result trigger the notification.
+				return nil
+			}
+			return err
+		}
+		if ok, present := prev.OK(builder, ""); present && ok {
+			broken = com
+		}
+	}
+	var err os.Error
+	if broken != nil && !broken.FailNotificationSent {
+		c.Infof("%s is broken commit; notifying", broken.Hash)
+		sendFailMailLater.Call(c, broken, builder) // add task to queue
+		broken.FailNotificationSent = true
+		_, err = datastore.Put(c, broken.Key(c), broken)
+	}
+	return err
+}
+
+// firstMatch executes the query q and loads the first entity into v.
+func firstMatch(c appengine.Context, q *datastore.Query, v interface{}) os.Error {
+	t := q.Limit(1).Run(c)
+	_, err := t.Next(v)
+	if err == datastore.Done {
+		err = datastore.ErrNoSuchEntity
+	}
+	return err
+}
+
+var (
+	sendFailMailLater = delay.Func("sendFailMail", sendFailMail)
+	sendFailMailTmpl  = template.Must(
+		template.New("notify").Funcs(tmplFuncs).ParseFile("build/notify.txt"),
+	)
+)
+
+func init() {
+	gob.Register(&Commit{}) // for delay
+}
+
+// sendFailMail sends a mail notification that the build failed on the
+// provided commit and builder.
+func sendFailMail(c appengine.Context, com *Commit, builder string) {
+	// TODO(adg): handle packages
+
+	// get Result
+	r := com.Result(builder, "")
+	if r == nil {
+		c.Errorf("finding result for %q: %+v", builder, com)
+		return
+	}
+
+	// get Log
+	k := datastore.NewKey(c, "Log", r.LogHash, 0, nil)
+	l := new(Log)
+	if err := datastore.Get(c, k, l); err != nil {
+		c.Errorf("finding Log record %v: %v", r.LogHash, err)
+		return
+	}
+
+	// prepare mail message
+	var body bytes.Buffer
+	err := sendFailMailTmpl.Execute(&body, map[string]interface{}{
+		"Builder": builder, "Commit": com, "Result": r, "Log": l,
+		"Hostname": domain,
+	})
+	if err != nil {
+		c.Errorf("rendering mail template: %v", err)
+		return
+	}
+	subject := fmt.Sprintf("%s broken by %s", builder, shortDesc(com.Desc))
+	msg := &mail.Message{
+		Sender:  mailFrom,
+		To:      []string{failMailTo},
+		ReplyTo: failMailTo,
+		Subject: subject,
+		Body:    body.String(),
+	}
+
+	// send mail
+	if err := mail.Send(c, msg); err != nil {
+		c.Errorf("sending mail: %v", err)
+	}
+}