build: relay exitcode from imagebuildah to registry

Podman does not relay exit code from buildah instead returns a generic
error code `125`. Following PR allows `podman` to relay exit code from
`imagebuildah` to `registry` as it is.

Signed-off-by: Aditya Rajan <arajan@redhat.com>

cmd/podman/images/build.go

@@ -1,9 +1,11 @@
 package images
 
 import (
+	"fmt"
 	"io"
 	"io/ioutil"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"strings"
 	"time"
@@ -289,7 +291,23 @@ func build(cmd *cobra.Command, args []string) error {
 	}
 
 	report, err := registry.ImageEngine().Build(registry.GetContext(), containerFiles, *apiBuildOpts)
+
 	if err != nil {
+		exitCode := buildahCLI.ExecErrorCodeGeneric
+		if registry.IsRemote() {
+			// errors from server does not contain ExitCode
+			// so parse exit code from error message
+			remoteExitCode, parseErr := utils.ExitCodeFromBuildError(fmt.Sprint(errors.Cause(err)))
+			if parseErr == nil {
+				exitCode = remoteExitCode
+			}
+		}
+
+		if ee, ok := (errors.Cause(err)).(*exec.ExitError); ok {
+			exitCode = ee.ExitCode()
+		}
+
+		registry.SetExitCode(exitCode)
 		return err
 	}
 

cmd/podman/utils/error.go

@@ -1,8 +1,13 @@
 package utils
 
 import (
+	"errors"
 	"fmt"
 	"os"
+	"strconv"
+	"strings"
+
+	buildahCLI "github.com/containers/buildah/pkg/cli"
 )
 
 type OutputErrors []error
@@ -17,3 +22,24 @@ func (o OutputErrors) PrintErrors() (lastError error) {
 	}
 	return
 }
+
+/* For remote client, server does not returns error with exit code
+   instead returns a message and we cast it to a new error.
+
+   Following function performs parsing on build error and returns
+   exit status which was exepected for this current build
+*/
+func ExitCodeFromBuildError(errorMsg string) (int, error) {
+	if strings.Contains(errorMsg, "exit status") {
+		errorSplit := strings.Split(errorMsg, " ")
+		if errorSplit[len(errorSplit)-2] == "status" {
+			tmpSplit := strings.Split(errorSplit[len(errorSplit)-1], "\n")
+			exitCodeRemote, err := strconv.Atoi(tmpSplit[0])
+			if err == nil {
+				return exitCodeRemote, nil
+			}
+			return buildahCLI.ExecErrorCodeGeneric, err
+		}
+	}
+	return buildahCLI.ExecErrorCodeGeneric, errors.New("error message does not contains a valid exit code")
+}

test/e2e/build_test.go

@@ -273,6 +273,23 @@ RUN printenv http_proxy`, ALPINE)
 		os.Unsetenv("http_proxy")
 	})
 
+	It("podman build relay exit code to process", func() {
+		if IsRemote() {
+			// following states true for all the remote commands
+			Skip("Remote server does not emits error with exit status")
+		}
+		podmanTest.AddImageToRWStore(ALPINE)
+		dockerfile := fmt.Sprintf(`FROM %s
+RUN exit 5`, ALPINE)
+
+		dockerfilePath := filepath.Join(podmanTest.TempDir, "Dockerfile")
+		err := ioutil.WriteFile(dockerfilePath, []byte(dockerfile), 0755)
+		Expect(err).To(BeNil())
+		session := podmanTest.Podman([]string{"build", "-t", "error-test", "--file", dockerfilePath, podmanTest.TempDir})
+		session.Wait(120)
+		Expect(session).Should(Exit(5))
+	})
+
 	It("podman build and check identity", func() {
 		session := podmanTest.Podman([]string{"build", "--pull-never", "-f", "build/basicalpine/Containerfile.path", "--no-cache", "-t", "test", "build/basicalpine"})
 		session.WaitWithDefaultTimeout()