Add nohosts option to /build and /libpod/build

Signed-off-by: Gavin Lam <gavin.oss@tutamail.com>

pkg/api/handlers/compat/images_build.go

@@ -142,6 +142,7 @@ func BuildImage(w http.ResponseWriter, r *http.Request) {
 		Memory                  int64    `schema:"memory"`
 		NamespaceOptions        string   `schema:"nsoptions"`
 		NoCache                 bool     `schema:"nocache"`
+		NoHosts                 bool     `schema:"nohosts"`
 		OmitHistory             bool     `schema:"omithistory"`
 		OSFeatures              []string `schema:"osfeature"`
 		OSVersion               string   `schema:"osversion"`
@@ -720,6 +721,7 @@ func BuildImage(w http.ResponseWriter, r *http.Request) {
 			LabelOpts:          labelOpts,
 			Memory:             query.Memory,
 			MemorySwap:         query.MemSwap,
+			NoHosts:            query.NoHosts,
 			OmitHistory:        query.OmitHistory,
 			SeccompProfilePath: seccomp,
 			ShmSize:            strconv.Itoa(query.ShmSize),

pkg/api/server/register_images.go

@@ -523,6 +523,12 @@ func (s *APIServer) registerImagesHandlers(r *mux.Router) error {
 	//      TBD Extra hosts to add to /etc/hosts
 	//      (As of version 1.xx)
 	//  - in: query
+	//    name: nohosts
+	//    type: boolean
+	//    default:
+	//    description: |
+	//      Not to create /etc/hosts when building the image
+	//  - in: query
 	//    name: remote
 	//    type: string
 	//    default:
@@ -1502,6 +1508,12 @@ func (s *APIServer) registerImagesHandlers(r *mux.Router) error {
 	//      TBD Extra hosts to add to /etc/hosts
 	//      (As of version 1.xx)
 	//  - in: query
+	//    name: nohosts
+	//    type: boolean
+	//    default:
+	//    description: |
+	//      Not to create /etc/hosts when building the image
+	//  - in: query
 	//    name: remote
 	//    type: string
 	//    default:

pkg/bindings/images/build.go

@@ -335,6 +335,9 @@ func Build(ctx context.Context, containerFiles []string, options types.BuildOpti
 	if options.NoCache {
 		params.Set("nocache", "1")
 	}
+	if options.CommonBuildOpts.NoHosts {
+		params.Set("nohosts", "1")
+	}
 	if t := options.Output; len(t) > 0 {
 		params.Set("output", t)
 	}

test/e2e/build_test.go

@@ -737,6 +737,31 @@ RUN [[ -L /test/dummy-symlink ]] && echo SYMLNKOK || echo SYMLNKERR`, CITEST_IMA
 		Expect(session.OutputToString()).To(ContainSubstring("SYMLNKOK"))
 	})
 
+	It("podman build --no-hosts", func() {
+		targetPath := podmanTest.TempDir
+
+		containerFile := filepath.Join(targetPath, "Containerfile")
+		content := `FROM scratch
+RUN echo '56.78.12.34 image.example.com' > /etc/hosts`
+
+		Expect(os.WriteFile(containerFile, []byte(content), 0755)).To(Succeed())
+
+		defer func() {
+			Expect(os.RemoveAll(containerFile)).To(Succeed())
+		}()
+
+		session := podmanTest.Podman([]string{
+			"build", "--pull-never", "-t", "hosts_test", "--no-hosts", "--from", CITEST_IMAGE, targetPath,
+		})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(ExitCleanly())
+
+		session = podmanTest.Podman([]string{"run", "--no-hosts", "--rm", "hosts_test", "cat", "/etc/hosts"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(ExitCleanly())
+		Expect(session.OutputToString()).To(Equal("56.78.12.34 image.example.com"))
+	})
+
 	It("podman build --from, --add-host, --cap-drop, --cap-add", func() {
 		targetPath := podmanTest.TempDir