roll.go: add a flag to send the CL to the gardener

Bug: dawn:1940
Change-Id: I720d8f6507a18bfd50dcaa1ae8db34b566c7c469
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/147542
Auto-Submit: Austin Eng <[email protected]>
Reviewed-by: Ben Clayton <[email protected]>
Kokoro: Kokoro <[email protected]>
Commit-Queue: Austin Eng <[email protected]>

tools/src/cmd/cts/roll/roll.go

@@ -17,9 +17,12 @@ package roll
 import (
  "bytes"
  "context"
+ "encoding/json"
  "flag"
  "fmt"
+ "io/ioutil"
  "log"
+ "net/http"
  "os"
  "os/exec"
  "path/filepath"
@@ -65,14 +68,15 @@ const (
 )
 
 type rollerFlags struct {
- gitPath string
- npmPath string
- nodePath string
- auth authcli.Flags
- cacheDir string
- force bool // Create a new roll, even if CTS is up to date
- rebuild bool // Rebuild the expectations file from scratch
- preserve bool // If false, abandon past roll changes
+ gitPath string
+ npmPath string
+ nodePath string
+ auth authcli.Flags
+ cacheDir string
+ force bool // Create a new roll, even if CTS is up to date
+ rebuild bool // Rebuild the expectations file from scratch
+ preserve bool // If false, abandon past roll changes
+ sendToGardener bool // If true, automatically send to the gardener for review
 }
 
 type cmd struct {
@@ -99,6 +103,7 @@ func (c *cmd) RegisterFlags(ctx context.Context, cfg common.Config) ([]string, e
  flag.BoolVar(&c.flags.force, "force", false, "create a new roll, even if CTS is up to date")
  flag.BoolVar(&c.flags.rebuild, "rebuild", false, "rebuild the expectation file from scratch")
  flag.BoolVar(&c.flags.preserve, "preserve", false, "do not abandon existing rolls")
+ flag.BoolVar(&c.flags.sendToGardener, "send-to-gardener", false, "send the CL to the WebGPU gardener for review")
 
  return nil, nil
 }
@@ -396,7 +401,33 @@ func (r *roller) roll(ctx context.Context) error {
  }
  }
 
- if err := r.gerrit.SetReadyForReview(changeID, "CTS roll succeeded"); err != nil {
+ reviewer := ""
+ if r.flags.sendToGardener {
+ resp, err := http.Get("https://chrome-ops-rotation-proxy.appspot.com/current/grotation:webgpu-gardener")
+ if err != nil {
+ return err
+ }
+ defer resp.Body.Close()
+
+ jsonResponse, err := ioutil.ReadAll(resp.Body)
+ if err != nil {
+ return err
+ }
+
+ type StructuredJsonResponse struct {
+ Emails []string
+ }
+ var jsonRes StructuredJsonResponse
+ if err := json.Unmarshal(jsonResponse, &jsonRes); err != nil {
+ return err
+ }
+ if len(jsonRes.Emails) < 1 {
+ return fmt.Errorf("Expected at least one email in JSON response %s", jsonRes)
+ }
+ reviewer = jsonRes.Emails[0]
+ }
+
+ if err := r.gerrit.SetReadyForReview(changeID, "CTS roll succeeded", reviewer); err != nil {
  return fmt.Errorf("failed to mark change as ready for review: %v", err)
  }
 

tools/src/gerrit/gerrit.go

@@ -19,6 +19,7 @@ import (
  "context"
  "flag"
  "fmt"
+ "log"
  "net/url"
  "strconv"
  "strings"
@@ -311,12 +312,24 @@ func (g *Gerrit) Comment(ps Patchset, msg string, comments []FileComment) error
 }
 
 // SetReadyForReview marks the change as ready for review.
-func (g *Gerrit) SetReadyForReview(changeID, message string) error {
+func (g *Gerrit) SetReadyForReview(changeID, message, reviewer string) error {
  resp, err := g.client.Changes.SetReadyForReview(changeID, &gerrit.ReadyForReviewInput{
  Message: message,
  })
  if err != nil && resp.StatusCode != 409 { // 409: already ready
  return err
  }
+ if reviewer != "" {
+ // Log the reviewer and then replace with enga@.
+ // TODO(crbug.com/dawn/1940): Use the actual reviewer when the bot is stable.
+ log.Printf("Got reviewer %s", reviewer)
+ reviewer = "[email protected]"
+ _, resp, err = g.client.Changes.AddReviewer(changeID, &gerrit.ReviewerInput{
+ Reviewer: reviewer,
+ })
+ if err != nil && resp.StatusCode != 409 { // 409: already ready
+ return err
+ }
+ }
  return nil
 }