fix: piping input in gator (#2589)

Co-authored-by: Sertaç Özercan <852750+sozercan@users.noreply.github.com>

pkg/gator/reader/filereader.go

@@ -148,7 +148,8 @@ func readStdin() ([]*unstructured.Unstructured, error) {
 		return nil, fmt.Errorf("getting stdin info: %w", err)
 	}
 
-	if stdinfo.Size() == 0 {
+	// check if data is being piped or redirected to stdin
+	if (stdinfo.Mode() & os.ModeCharDevice) != 0 {
 		return nil, nil
 	}
 

test/gator/test/test.bats

@@ -46,6 +46,11 @@ match_yaml_msg () {
 # END OF HELPER FUNCTIONS
 ####################################################################################################
 
+@test "gator test doesn't wait on stdin input" {
+  # this should fail with "no input data identified"
+  ! bin/gator test
+}
+
 @test "manifest with no violations piped to stdin returns 0 exit status" {
   bin/gator test < "$BATS_TEST_DIRNAME/fixtures/manifests/with-policies/no-violations.yaml"
   if [ "$?" -ne 0 ]; then
@@ -54,10 +59,20 @@ match_yaml_msg () {
   fi
 }
 
-@test "manifest with violations piped to stdin returns 1 exit status" {
+@test "manifest with violations redirected to stdin returns 1 exit status" {
   ! bin/gator test < "$BATS_TEST_DIRNAME/fixtures/manifests/with-policies/with-violations.yaml"
 }
 
+@test "manifest with violations piped to stdin returns 1 exit status" {
+  # first test that we fail the command
+  ! cat "$BATS_TEST_DIRNAME/fixtures/manifests/with-policies/with-violations.yaml" | bin/gator test
+
+  output=$(! cat "$BATS_TEST_DIRNAME/fixtures/manifests/with-policies/with-violations.yaml" | bin/gator test)
+
+  # now test that the failure reason is a violation
+  match_substring "${output[*]}" "Container <tomcat> in your <Pod> <test-pod1> has no <readinessProbe>"
+}
+
 @test "manifest with no violations included as flag returns 0 exit status" {
   bin/gator test --filename="$BATS_TEST_DIRNAME/fixtures/manifests/with-policies/no-violations.yaml"
   if [ "$?" -ne 0 ]; then