top: fallback to execing ps(1)

Fallback to executing ps(1) in case we hit an unknown psgo descriptor.
This ensures backwards compatibility with docker-top, which was purely
ps(1) driven.

Also support comma-separated descriptors as input.

Signed-off-by: Valentin Rothberg <rothberg@redhat.com>

2 files changed, 32 insertions, 2 deletions

diff --git a/test/e2e/pod_top_test.go b/test/e2e/pod_top_test.go
index 964ee075f..420e4aca9 100644
--- a/test/e2e/pod_top_test.go
+++ b/test/e2e/pod_top_test.go
@@ -93,7 +93,11 @@ var _ = Describe("Podman top", func() {
 		session.WaitWithDefaultTimeout()
 		Expect(session.ExitCode()).To(Equal(0))
 
-		result := podmanTest.Podman([]string{"pod", "top", podid, "invalid"})
+		// We need to pass -eo to force executing ps in the Alpine container.
+		// Alpines stripped down ps(1) is accepting any kind of weird input in
+		// contrast to others, such that a `ps invalid` will silently ignore
+		// the wrong input and still print the -ef output instead.
+		result := podmanTest.Podman([]string{"pod", "top", podid, "-eo", "invalid"})
 		result.WaitWithDefaultTimeout()
 		Expect(result.ExitCode()).To(Equal(125))
 	})
diff --git a/test/e2e/top_test.go b/test/e2e/top_test.go
index 2d3a5629c..4c2cdb7b5 100644
--- a/test/e2e/top_test.go
+++ b/test/e2e/top_test.go
@@ -87,13 +87,39 @@ var _ = Describe("Podman top", func() {
 		Expect(len(result.OutputToStringArray())).To(BeNumerically(">", 1))
 	})
 
+	It("podman top with ps(1) options", func() {
+		session := podmanTest.Podman([]string{"run", "-d", ALPINE, "top", "-d", "2"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+
+		result := podmanTest.Podman([]string{"top", session.OutputToString(), "aux"})
+		result.WaitWithDefaultTimeout()
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(len(result.OutputToStringArray())).To(BeNumerically(">", 1))
+	})
+
+	It("podman top with comma-separated options", func() {
+		session := podmanTest.Podman([]string{"run", "-d", ALPINE, "top", "-d", "2"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+
+		result := podmanTest.Podman([]string{"top", session.OutputToString(), "user,pid,comm"})
+		result.WaitWithDefaultTimeout()
+		Expect(result.ExitCode()).To(Equal(0))
+		Expect(len(result.OutputToStringArray())).To(BeNumerically(">", 1))
+	})
+
 	It("podman top on container invalid options", func() {
 		top := podmanTest.RunTopContainer("")
 		top.WaitWithDefaultTimeout()
 		Expect(top.ExitCode()).To(Equal(0))
 		cid := top.OutputToString()
 
-		result := podmanTest.Podman([]string{"top", cid, "invalid"})
+		// We need to pass -eo to force executing ps in the Alpine container.
+		// Alpines stripped down ps(1) is accepting any kind of weird input in
+		// contrast to others, such that a `ps invalid` will silently ignore
+		// the wrong input and still print the -ef output instead.
+		result := podmanTest.Podman([]string{"top", cid, "-eo", "invalid"})
 		result.WaitWithDefaultTimeout()
 		Expect(result.ExitCode()).To(Equal(125))
 	})