Fix podman build --logfile

Currently this command blows up because it closes the file descriptor before
doing the build.

Add tests to make sure we don't regress.

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1877188

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

cmd/podman/images/build.go

@@ -211,7 +211,16 @@ func build(cmd *cobra.Command, args []string) error {
 		return err
 	}
 
-	apiBuildOpts, err := buildFlagsWrapperToOptions(cmd, contextDir, &buildOpts)
+	var logfile *os.File
+	if cmd.Flag("logfile").Changed {
+		logfile, err = os.OpenFile(buildOpts.Logfile, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, 0600)
+		if err != nil {
+			return errors.Errorf("error opening logfile %q: %v", buildOpts.Logfile, err)
+		}
+		defer logfile.Close()
+	}
+
+	apiBuildOpts, err := buildFlagsWrapperToOptions(cmd, contextDir, &buildOpts, logfile)
 	if err != nil {
 		return err
 	}
@@ -225,7 +234,7 @@ func build(cmd *cobra.Command, args []string) error {
 // conversion here prevents the API from doing that (redundantly).
 //
 // TODO: this code should really be in Buildah.
-func buildFlagsWrapperToOptions(c *cobra.Command, contextDir string, flags *buildFlagsWrapper) (*entities.BuildOptions, error) {
+func buildFlagsWrapperToOptions(c *cobra.Command, contextDir string, flags *buildFlagsWrapper, logfile *os.File) (*entities.BuildOptions, error) {
 	output := ""
 	tags := []string{}
 	if c.Flag("tag").Changed {
@@ -284,16 +293,11 @@ func buildFlagsWrapperToOptions(c *cobra.Command, contextDir string, flags *buil
 	stderr = os.Stderr
 	reporter = os.Stderr
 
-	if c.Flag("logfile").Changed {
+	if logfile != nil {
-		f, err := os.OpenFile(flags.Logfile, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, 0600)
+		logrus.SetOutput(logfile)
-		if err != nil {
+		stdout = logfile
-			return nil, errors.Errorf("error opening logfile %q: %v", flags.Logfile, err)
+		stderr = logfile
-		}
+		reporter = logfile
-		defer f.Close()
-		logrus.SetOutput(f)
-		stdout = f
-		stderr = f
-		reporter = f
 	}
 
 	var memoryLimit, memorySwap int64

test/e2e/build_test.go

@@ -57,6 +57,29 @@ var _ = Describe("Podman build", func() {
 		Expect(session.ExitCode()).To(Equal(0))
 	})
 
+	It("podman build with logfile", func() {
+		SkipIfRemote()
+		logfile := filepath.Join(podmanTest.TempDir, "logfile")
+		session := podmanTest.PodmanNoCache([]string{"build", "--tag", "test", "--logfile", logfile, "build/basicalpine"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+
+		// Verify that OS and Arch are being set
+		inspect := podmanTest.PodmanNoCache([]string{"inspect", "test"})
+		inspect.WaitWithDefaultTimeout()
+		data := inspect.InspectImageJSON()
+		Expect(data[0].Os).To(Equal(runtime.GOOS))
+		Expect(data[0].Architecture).To(Equal(runtime.GOARCH))
+
+		st, err := os.Stat(logfile)
+		Expect(err).To(BeNil())
+		Expect(st.Size()).To(Not(Equal(0)))
+
+		session = podmanTest.PodmanNoCache([]string{"rmi", "alpine"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+	})
+
 	// If the context directory is pointing at a file and not a directory,
 	// that's a no no, fail out.
 	It("podman build context directory a file", func() {