Merge pull request #509 from yuumasato/handle-no-objects-to-iterate-o…

…n-filter

OCPBUGS-33067: Don't fatal error when filter cannot iterate

cmd/manager/scap.go

@@ -52,6 +52,7 @@ const (
 
 var (
  MoreThanOneObjErr = errors.New("more than one object returned from the filter")
+ NullValErr = errors.New("no value was returned from the filter")
 )
 
 // resourceFetcherClients just gathers several needed structs together so we can
@@ -520,6 +521,8 @@ func fetch(ctx context.Context, streamDispatcher streamerDispatcherFn, rfClients
  filteredBody, filterErr := filter(ctx, body, rpath.Filter)
  if errors.Is(filterErr, MoreThanOneObjErr) {
  warnings = append(warnings, filterErr.Error())
+ } else if errors.Is(filterErr, NullValErr) {
+ warnings = append(warnings, fmt.Sprintf("couldn't filter '%s': %s", body, filterErr.Error()))
  } else if filterErr != nil {
  return fmt.Errorf("couldn't filter '%s': %w", body, filterErr)
  }
@@ -554,6 +557,11 @@ func filter(ctx context.Context, rawobj []byte, filter string) ([]byte, error) {
  }
  if err, ok := v.(error); ok {
  DBG("Error while filtering: %s", err)
+ // gojq may return a diverse set of internal errors caused by null values.
+ // These errors are happen when a piped filter ends up acting on a null value.
+ if strings.HasSuffix(err.Error(), ": null") {
+ return nil, fmt.Errorf("Skipping empty filter result from '%s': %w", filter, NullValErr)
+ }
  return nil, err
  }
 

cmd/manager/scap_test.go

@@ -316,6 +316,20 @@ var _ = Describe("Testing filtering", func() {
  Expect(filterErr).Should(MatchError(MoreThanOneObjErr))
  })
  })
+ Context("Piped Filtering", func() {
+ var rawmc []byte
+ BeforeEach(func() {
+ nsFile, err := os.Open("../../tests/data/empty_machineconfig.json")
+ Expect(err).To(BeNil())
+ var readErr error
+ rawmc, readErr = io.ReadAll(nsFile)
+ Expect(readErr).To(BeNil())
+ })
+ It("skips filter piping errors", func() {
+ _, filterErr := filter(context.TODO(), rawmc, `[.items[] | select(.metadata.name | test("^rendered-worker-[0-9a-z]+$|^rendered-master-[0-9a-z]+$"))] | map(.spec.fips == true)`)
+ Expect(filterErr).Should(MatchError(NullValErr))
+ })
+ })
  })
 })
 

tests/data/empty_machineconfig.json

@@ -0,0 +1,4 @@
+{
+ "metadata": {},
+ "items": null
+}