Merge pull request #793 from alicerum/check-taskruns

Check for Tekton installed before running the manager

cmd/shipwright-build-controller/main.go

@@ -8,13 +8,17 @@ import (
 	"context"
 	"flag"
 	"fmt"
+	"io/ioutil"
 	"os"
 	"runtime"
 
 	// Import all Kubernetes client auth plugins (e.g. Azure, GCP, OIDC, etc.)
 
 	"github.com/spf13/pflag"
+	"github.com/tektoncd/pipeline/pkg/apis/pipeline"
+	pipelinev1beta1 "github.com/tektoncd/pipeline/pkg/apis/pipeline/v1beta1"
 
+	"k8s.io/apimachinery/pkg/api/meta"
 	_ "k8s.io/client-go/plugin/pkg/client/auth"
 	"sigs.k8s.io/controller-runtime/pkg/client/config"
 	"sigs.k8s.io/controller-runtime/pkg/manager"
@@ -95,6 +99,25 @@ func main() {
 		os.Exit(1)
 	}
 
+	// check for pipelines to exist and be available
+	installed, err := checkForPipelinesInstalled(mgr)
+	if err != nil {
+		ctxlog.Error(ctx, err, "Error while checking for TaskRuns")
+		os.Exit(1)
+	}
+	if !installed {
+		msg := "Cannot start manager: Tekton Pipelines are not installed on the cluster"
+
+		// we also want to put this into the termination log
+		// so that user can see this message as the reason pod failed
+		if err := ioutil.WriteFile(buildCfg.TerminationLogPath, []byte(msg), 0644); err != nil {
+			ctxlog.Error(ctx, err, "Error while trying to write to termination log")
+		}
+
+		ctxlog.Error(ctx, nil, msg)
+		os.Exit(1)
+	}
+
 	buildMetrics.InitPrometheus(buildCfg)
 
 	// Add optionally configured extra handlers to metrics endpoint
@@ -113,3 +136,21 @@ func main() {
 		os.Exit(1)
 	}
 }
+
+// checkForPipelinesInstalled tries to find the "TaskRun" resource on the api
+// returns (true, nil) if resource is found, (false, nil) otherwise
+// and error as second return parameter in case of failed request
+func checkForPipelinesInstalled(mgr manager.Manager) (bool, error) {
+	rm := mgr.GetRESTMapper()
+
+	_, err := rm.KindFor(pipeline.TaskRunResource.WithVersion(pipelinev1beta1.SchemeGroupVersion.Version))
+	if err != nil {
+		if meta.IsNoMatchError(err) {
+			return false, nil
+		}
+
+		return false, err
+	}
+
+	return true, nil
+}

docs/configuration.md

@@ -27,3 +27,4 @@ The following environment variables are available:
 | `CLUSTERBUILDSTRATEGY_MAX_CONCURRENT_RECONCILES` | The number of concurrent reconciles by the clusterbuildstrategy controller. A value of 0 or lower will use the default from the [controller-runtime controller Options](https://pkg.go.dev/sigs.k8s.io/controller-runtime/pkg/controller#Options). Default is 0. |
 | `KUBE_API_BURST` | Burst to use for the Kubernetes API client. See [Config.Burst](https://pkg.go.dev/k8s.io/client-go/rest#Config.Burst). A value of 0 or lower will use the default from client-go, which currently is 10. Default is 0. |
 | `KUBE_API_QPS` | QPS to use for the Kubernetes API client. See [Config.QPS](https://pkg.go.dev/k8s.io/client-go/rest#Config.QPS). A value of 0 or lower will use the default from client-go, which currently is 5. Default is 0. |
+| `TERMINATION_LOG_PATH` | Path of the termination log. This is where controller application will write the reason of its termination. Default value is `/dev/termination-log`. |

pkg/config/config.go

@@ -59,6 +59,9 @@ const (
 	// environment variables for the kube API
 	kubeAPIBurst = "KUBE_API_BURST"
 	kubeAPIQPS   = "KUBE_API_QPS"
+
+	terminationLogPathDefault = "/dev/termination-log"
+	terminationLogPathEnvVar  = "TERMINATION_LOG_PATH"
 )
 
 var (
@@ -77,6 +80,7 @@ type Config struct {
 	GitContainerTemplate          corev1.Container
 	KanikoContainerImage          string
 	RemoteArtifactsContainerImage string
+	TerminationLogPath            string
 	Prometheus                    PrometheusConfig
 	ManagerOptions                ManagerOptions
 	Controllers                   Controllers
@@ -160,6 +164,7 @@ func NewDefaultConfig() *Config {
 			QPS:   0,
 			Burst: 0,
 		},
+		TerminationLogPath: terminationLogPathDefault,
 	}
 }
 
@@ -248,6 +253,10 @@ func (c *Config) SetConfigFromEnv() error {
 		return err
 	}
 
+	if terminationLogPath := os.Getenv(terminationLogPathEnvVar); terminationLogPath != "" {
+		c.TerminationLogPath = terminationLogPath
+	}
+
 	return nil
 }