Handle errors better in table views

cmd/printers/table/collector.go

@@ -48,6 +48,8 @@ type ResourceStateCollector struct {
 	// resource identifier to a ResourceInfo object that captures
 	// the latest state for the given resource.
 	resourceInfos map[object.ObjMetadata]*ResourceInfo
+
+	err error
 }
 
 // ResourceInfo captures the latest seen state of a single resource.
@@ -185,8 +187,7 @@ func (r *ResourceStateCollector) processApplyEvent(e event.ApplyEvent) {
 
 // processErrorEvent handles events for errors.
 func (r *ResourceStateCollector) processErrorEvent(err error) {
-	// TODO: Handle errors more gracefully than this.
-	panic(err)
+	r.err = err
 }
 
 // toIdentifier extracts the identifying information from an
@@ -202,19 +203,25 @@ func toIdentifier(o runtime.Object) object.ObjMetadata {
 
 // ResourceState contains the latest state for all the resources.
 type ResourceState struct {
-	ResourceInfos ResourceInfos
+	resourceInfos ResourceInfos
+
+	err error
 }
 
 // Resources returns a slice containing the latest state
 // for each individual resource.
 func (r *ResourceState) Resources() []table.Resource {
 	var resources []table.Resource
-	for _, res := range r.ResourceInfos {
+	for _, res := range r.resourceInfos {
 		resources = append(resources, res)
 	}
 	return resources
 }
 
+func (r *ResourceState) Error() error {
+	return r.err
+}
+
 // LatestState returns a ResourceState object that contains
 // a copy of the latest state for all resources.
 func (r *ResourceStateCollector) LatestState() *ResourceState {
@@ -233,7 +240,8 @@ func (r *ResourceStateCollector) LatestState() *ResourceState {
 	sort.Sort(resourceInfos)
 
 	return &ResourceState{
-		ResourceInfos: resourceInfos,
+		resourceInfos: resourceInfos,
+		err:           r.err,
 	}
 }
 

cmd/printers/table/printer.go

@@ -30,7 +30,8 @@ func (t *Printer) Print(ch <-chan event.Event, _ bool) {
 		// Eventually we need a more graceful shutdown if
 		// this happens.
 		if e.Type == event.ErrorType {
-			panic(e.ErrorEvent.Err)
+			_, _ = fmt.Fprintf(t.IOStreams.Out, "Fatal error: %v\n", e.ErrorEvent.Err)
+			return
 		}
 	}
 	// Create a new collector and initialize it with the resources

cmd/status/printers/adapter.go

@@ -41,12 +41,17 @@ func (r *ResourceInfo) SubResources() []table.Resource {
 
 type ResourceState struct {
 	resources []table.Resource
+	err       error
 }
 
 func (rss *ResourceState) Resources() []table.Resource {
 	return rss.resources
 }
 
+func (rss *ResourceState) Error() error {
+	return rss.err
+}
+
 func (ca *CollectorAdapter) LatestStatus() *ResourceState {
 	observation := ca.collector.LatestObservation()
 	var resources []table.Resource
@@ -57,5 +62,6 @@ func (ca *CollectorAdapter) LatestStatus() *ResourceState {
 	}
 	return &ResourceState{
 		resources: resources,
+		err:       observation.Error,
 	}
 }

pkg/print/table/base.go

@@ -28,6 +28,7 @@ type ColumnDefinition interface {
 // that should be printed.
 type ResourceStates interface {
 	Resources() []Resource
+	Error() error
 }
 
 // Resource defines the interface that each of the Resource
@@ -58,8 +59,12 @@ func (t *BaseTablePrinter) PrintTable(rs ResourceStates,
 		t.moveUp()
 		t.eraseCurrentLine()
 	}
-	linePrintCount := 0
 
+	if rs.Error() != nil {
+		return t.printError(rs.Error())
+	}
+
+	linePrintCount := 0
 	for i, column := range t.Columns {
 		format := fmt.Sprintf("%%-%ds", column.Width())
 		t.printOrDie(format, column.Header())
@@ -136,6 +141,11 @@ func (t *BaseTablePrinter) printSubTable(resources []Resource,
 	return linePrintCount
 }
 
+func (t *BaseTablePrinter) printError(err error) int {
+	t.printOrDie("Fatal error: %v\n", err)
+	return 1 // This is the number of lines printed.
+}
+
 func (t *BaseTablePrinter) printOrDie(format string, a ...interface{}) {
 	_, err := fmt.Fprintf(t.IOStreams.Out, format, a...)
 	if err != nil {

pkg/print/table/base_test.go

@@ -161,6 +161,10 @@ func (r *fakeResourceStates) Resources() []Resource {
 	return r.resources
 }
 
+func (r *fakeResourceStates) Error() error {
+	return nil
+}
+
 type fakeResource struct {
 	resourceStatus *pe.ResourceStatus
 }