Merge pull request #13952 from krzyzacy/actually-patch-plank

Try to update prowjobs in plank use patch (third time the charm!)

Author: k8s-ci-robot

prow/plank/BUILD.bazel

@@ -43,10 +43,12 @@ go_library(
         "//prow/kube:go_default_library",
         "//prow/pjutil:go_default_library",
         "//prow/pod-utils/decorate:go_default_library",
+        "@com_github_evanphx_json_patch//:go_default_library",
         "@com_github_sirupsen_logrus//:go_default_library",
         "@io_k8s_api//core/v1:go_default_library",
         "@io_k8s_apimachinery//pkg/api/errors:go_default_library",
         "@io_k8s_apimachinery//pkg/apis/meta/v1:go_default_library",
+        "@io_k8s_apimachinery//pkg/types:go_default_library",
         "@io_k8s_client_go//kubernetes/typed/core/v1:go_default_library",
     ],
 )

prow/plank/controller.go

@@ -17,16 +17,19 @@ limitations under the License.
 package plank
 
 import (
+	"encoding/json"
 	"fmt"
 	"sort"
 	"strings"
 	"sync"
 	"time"
 
+	jsonpatch "github.com/evanphx/json-patch"
 	"github.com/sirupsen/logrus"
 	coreapi "k8s.io/api/core/v1"
 	v1 "k8s.io/api/core/v1"
 	kerrors "k8s.io/apimachinery/pkg/api/errors"
+	ktypes "k8s.io/apimachinery/pkg/types"
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	corev1 "k8s.io/client-go/kubernetes/typed/core/v1"
@@ -51,6 +54,7 @@ type prowJobClient interface {
 	Update(*prowapi.ProwJob) (*prowapi.ProwJob, error)
 	Get(name string, options metav1.GetOptions) (*prowapi.ProwJob, error)
 	List(opts metav1.ListOptions) (*prowapi.ProwJobList, error)
+	Patch(name string, pt ktypes.PatchType, data []byte, subresources ...string) (result *prowapi.ProwJob, err error)
 }
 
 // GitHubClient contains the methods used by plank on k8s.io/test-infra/prow/github.Client
@@ -349,6 +353,7 @@ func syncProwJobs(
 func (c *Controller) syncPendingJob(pj prowapi.ProwJob, pm map[string]coreapi.Pod, reports chan<- prowapi.ProwJob) error {
 	// Record last known state so we can log state transitions.
 	prevState := pj.Status.State
+	prevPJ := pj
 
 	pod, podExists := pm[pj.ObjectMeta.Name]
 	if !podExists {
@@ -474,14 +479,14 @@ func (c *Controller) syncPendingJob(pj prowapi.ProwJob, pm map[string]coreapi.Po
 			WithField("from", prevState).
 			WithField("to", pj.Status.State).Info("Transitioning states.")
 	}
-	_, err := c.prowJobClient.Update(&pj)
-	c.log.WithFields(pjutil.ProwJobFields(&pj)).Debug("Update ProwJob.")
-	return err
+
+	return c.patchProwjob(prevPJ, pj)
 }
 
 func (c *Controller) syncTriggeredJob(pj prowapi.ProwJob, pm map[string]coreapi.Pod, reports chan<- prowapi.ProwJob) error {
 	// Record last known state so we can log state transitions.
 	prevState := pj.Status.State
+	prevPJ := pj
 
 	var id, pn string
 	pod, podExists := pm[pj.ObjectMeta.Name]
@@ -525,9 +530,7 @@ func (c *Controller) syncTriggeredJob(pj prowapi.ProwJob, pm map[string]coreapi.
 			WithField("from", prevState).
 			WithField("to", pj.Status.State).Info("Transitioning states.")
 	}
-	_, err := c.prowJobClient.Update(&pj)
-	c.log.WithFields(pjutil.ProwJobFields(&pj)).Debug("Update ProwJob.")
-	return err
+	return c.patchProwjob(prevPJ, pj)
 }
 
 // TODO: No need to return the pod name since we already have the
@@ -568,3 +571,24 @@ func getPodBuildID(pod *coreapi.Pod) string {
 	logrus.Warningf("BUILD_ID was not found in pod %q: streaming logs from deck will not work", pod.ObjectMeta.Name)
 	return ""
 }
+
+func (c *Controller) patchProwjob(srcPJ prowapi.ProwJob, destPJ prowapi.ProwJob) error {
+	srcPJData, err := json.Marshal(srcPJ)
+	if err != nil {
+		return fmt.Errorf("marshal source prow job: %v", err)
+	}
+
+	destPJData, err := json.Marshal(destPJ)
+	if err != nil {
+		return fmt.Errorf("marshal dest prow job: %v", err)
+	}
+
+	patch, err := jsonpatch.CreateMergePatch(srcPJData, destPJData)
+	if err != nil {
+		return fmt.Errorf("cannot create JSON patch: %v", err)
+	}
+
+	_, err = c.prowJobClient.Patch(srcPJ.Name, ktypes.MergePatchType, patch)
+	c.log.WithFields(pjutil.ProwJobFields(&destPJ)).Debug("Patched ProwJob.")
+	return err
+}