From fa30e9d338af56f2d92bb45a46df48203ffd01f7 Mon Sep 17 00:00:00 2001 From: Michael Vogt Date: Mon, 26 Feb 2024 12:25:32 +0100 Subject: [PATCH] main: return different exit code when an input is not found This is a proof of concept that shows how we could do a different exit code in skopeo when an input is not found. The use case is `osbuild` which uses skopeo to inspect images and it would be nice to differenciate between an image that is not found and general skopeo errors (or errors like network issues etc). I picked exit code (2) for not found because it is also the value of ENOENT but that is arbitrary and I'm happy to switch to any other value (we could do `44` as `404` :-) - happy about ideas). Man page and a test are added. P.S. I also found that for local images that are not found `ErrNotAnImage` is returned so the docstring of `storage.ErrNotAnImage` may need updating (I'm happy to do this separtely if desired). To reproduce: ``` $ skopeo inspect containers-storage:010101010101 FATA[0000] Error parsing image name "containers-storage:010101010101": reference "[overlay@/media/space/home/egon/.local/share/containers/storage+/run/user/1000/containers]docker.io/library/010101010101:latest" does not resolve to an image ID: identifier is not an image ``` For references (from storage/errors.go): ``` ErrNotAnImage = errors.New("identifier is not an image") ``` Signed-off-by: Michael Vogt --- cmd/skopeo/main.go | 4 ++++ cmd/skopeo/proxy.go | 10 ---------- cmd/skopeo/utils.go | 12 ++++++++++++ docs/skopeo.1.md | 7 +++++++ systemtest/010-inspect.bats | 7 +++++++ systemtest/060-delete.bats | 2 +- 6 files changed, 31 insertions(+), 11 deletions(-) diff --git a/cmd/skopeo/main.go b/cmd/skopeo/main.go index 3617eeb2df..68b5b36b48 100644 --- a/cmd/skopeo/main.go +++ b/cmd/skopeo/main.go @@ -129,6 +129,10 @@ func main() { } rootCmd, _ := createApp() if err := rootCmd.Execute(); err != nil { + if isNotFoundImageError(err) { + logrus.Error(err) + logrus.Exit(2) + } logrus.Fatal(err) } } diff --git a/cmd/skopeo/proxy.go b/cmd/skopeo/proxy.go index aab85365b1..7f7266b6f7 100644 --- a/cmd/skopeo/proxy.go +++ b/cmd/skopeo/proxy.go @@ -73,7 +73,6 @@ import ( "github.com/containers/image/v5/image" "github.com/containers/image/v5/manifest" - ocilayout "github.com/containers/image/v5/oci/layout" "github.com/containers/image/v5/pkg/blobinfocache" "github.com/containers/image/v5/transports" "github.com/containers/image/v5/transports/alltransports" @@ -229,15 +228,6 @@ func isDockerManifestUnknownError(err error) bool { return ec.ErrorCode() == dockerdistributionapi.ErrorCodeManifestUnknown } -// isNotFoundImageError heuristically attempts to determine whether an error -// is saying the remote source couldn't find the image (as opposed to an -// authentication error, an I/O error etc.) -// TODO drive this into containers/image properly -func isNotFoundImageError(err error) bool { - return isDockerManifestUnknownError(err) || - errors.Is(err, ocilayout.ImageNotFoundError{}) -} - func (h *proxyHandler) openImageImpl(args []any, allowNotFound bool) (retReplyBuf replyBuf, retErr error) { h.lock.Lock() defer h.lock.Unlock() diff --git a/cmd/skopeo/utils.go b/cmd/skopeo/utils.go index 3fb0fab9e9..c462821463 100644 --- a/cmd/skopeo/utils.go +++ b/cmd/skopeo/utils.go @@ -12,9 +12,11 @@ import ( "github.com/containers/common/pkg/retry" "github.com/containers/image/v5/directory" "github.com/containers/image/v5/manifest" + ocilayout "github.com/containers/image/v5/oci/layout" "github.com/containers/image/v5/pkg/compression" "github.com/containers/image/v5/transports/alltransports" "github.com/containers/image/v5/types" + "github.com/containers/storage" imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1" "github.com/sirupsen/logrus" "github.com/spf13/cobra" @@ -406,3 +408,13 @@ func promptForPassphrase(privateKeyFile string, stdin, stdout *os.File) (string, fmt.Fprintf(stdout, "\n") return string(passphrase), nil } + +// isNotFoundImageError heuristically attempts to determine whether an error +// is saying the remote source couldn't find the image (as opposed to an +// authentication error, an I/O error etc.) +// TODO drive this into containers/image properly +func isNotFoundImageError(err error) bool { + return isDockerManifestUnknownError(err) || + errors.Is(err, storage.ErrNotAnImage) || + errors.Is(err, ocilayout.ImageNotFoundError{}) +} diff --git a/docs/skopeo.1.md b/docs/skopeo.1.md index 26583f1160..98209d497b 100644 --- a/docs/skopeo.1.md +++ b/docs/skopeo.1.md @@ -123,6 +123,13 @@ Print the version number Default directory containing registry configuration, if **--registries.d** is not specified. The contents of this directory are documented in [containers-registries.d(5)](https://github.com/containers/image/blob/main/docs/containers-registries.d.5.md). +## EXIT STATUS +`skopeo` exists with status 0 if the operation was successfully. Error result +in a non-zero exit code. If the input image cannot be found an exit status of +2 is returned. Note that this is best effort and for remote registries the +status often cannot be reliably reported. + + ## SEE ALSO skopeo-login(1), docker-login(1), containers-auth.json(5), containers-storage.conf(5), containers-policy.json(5), containers-transports(5) diff --git a/systemtest/010-inspect.bats b/systemtest/010-inspect.bats index 548174da48..6a8ad80989 100644 --- a/systemtest/010-inspect.bats +++ b/systemtest/010-inspect.bats @@ -129,4 +129,11 @@ END_EXPECT expect_output --from="$repo_tags" "" "inspect --no-tags was expected to return empty RepoTags[]" } +@test "inspect: image unknown" { + # non existing image + run_skopeo 2 inspect containers-storage:non-existing-tag + expect_output --substring "identifier is not an image" \ + "skopeo inspect containers-storage:010101010101" +} + # vim: filetype=sh diff --git a/systemtest/060-delete.bats b/systemtest/060-delete.bats index 09e6688a66..70b3a191b1 100644 --- a/systemtest/060-delete.bats +++ b/systemtest/060-delete.bats @@ -24,7 +24,7 @@ function setup() { run_skopeo delete --tls-verify=false $localimg # make sure image is removed from registry - expected_rc=1 + expected_rc=2 run_skopeo $expected_rc inspect --tls-verify=false $localimg }