Implement file action remove for wildcards

Signed-off-by: Edgar Lee <edgarl@netflix.com>

client/client_test.go

@@ -64,6 +64,7 @@ func TestIntegration(t *testing.T) {
 		testRelativeWorkDir,
 		testFileOpMkdirMkfile,
 		testFileOpCopyRm,
+		testFileOpRmWildcard,
 		testCallDiskUsage,
 		testBuildMultiMount,
 		testBuildHTTPSource,
@@ -1046,6 +1047,63 @@ func testFileOpCopyRm(t *testing.T, sb integration.Sandbox) {
 
 }
 
+func testFileOpRmWildcard(t *testing.T, sb integration.Sandbox) {
+	requiresLinux(t)
+	c, err := New(context.TODO(), sb.Address())
+	require.NoError(t, err)
+	defer c.Close()
+
+	dir, err := tmpdir(
+		fstest.CreateDir("foo", 0700),
+		fstest.CreateDir("bar", 0700),
+		fstest.CreateFile("foo/target", []byte("foo0"), 0600),
+		fstest.CreateFile("bar/target", []byte("bar0"), 0600),
+		fstest.CreateFile("bar/remaining", []byte("bar1"), 0600),
+	)
+	require.NoError(t, err)
+	defer os.RemoveAll(dir)
+
+	st := llb.Scratch().File(
+		llb.Copy(llb.Local("mylocal"), "foo", "foo").
+			Copy(llb.Local("mylocal"), "bar", "bar"),
+	).File(
+		llb.Rm("*/target", llb.WithAllowWildcard(true)),
+	)
+	def, err := st.Marshal()
+	require.NoError(t, err)
+
+	destDir, err := ioutil.TempDir("", "buildkit")
+	require.NoError(t, err)
+	defer os.RemoveAll(destDir)
+
+	_, err = c.Solve(context.TODO(), def, SolveOpt{
+		Exports: []ExportEntry{
+			{
+				Type:      ExporterLocal,
+				OutputDir: destDir,
+			},
+		},
+		LocalDirs: map[string]string{
+			"mylocal": dir,
+		},
+	}, nil)
+	require.NoError(t, err)
+
+	dt, err := ioutil.ReadFile(filepath.Join(destDir, "bar/remaining"))
+	require.NoError(t, err)
+	require.Equal(t, []byte("bar1"), dt)
+
+	fi, err := os.Stat(filepath.Join(destDir, "foo"))
+	require.NoError(t, err)
+	require.Equal(t, true, fi.IsDir())
+
+	_, err = os.Stat(filepath.Join(destDir, "foo/target"))
+	require.Equal(t, true, os.IsNotExist(err))
+
+	_, err = os.Stat(filepath.Join(destDir, "bar/target"))
+	require.Equal(t, true, os.IsNotExist(err))
+}
+
 func testCallDiskUsage(t *testing.T, sb integration.Sandbox) {
 	c, err := New(context.TODO(), sb.Address())
 	require.NoError(t, err)

solver/llbsolver/file/backend.go

@@ -100,13 +100,33 @@ func mkfile(ctx context.Context, d string, action pb.FileActionMkFile, user *cop
 }
 
 func rm(ctx context.Context, d string, action pb.FileActionRm) error {
-	p, err := fs.RootPath(d, filepath.Join(filepath.Join("/", action.Path)))
+	if action.AllowWildcard {
+		src := cleanPath(action.Path)
+		m, err := copy.ResolveWildcards(d, src, false)
+		if err != nil {
+			return err
+		}
+
+		for _, s := range m {
+			if err := rmPath(d, s, action.AllowNotFound); err != nil {
+				return err
+			}
+		}
+
+		return nil
+	}
+
+	return rmPath(d, action.Path, action.AllowNotFound)
+}
+
+func rmPath(root, src string, allowNotFound bool) error {
+	p, err := fs.RootPath(root, filepath.Join(filepath.Join("/", src)))
 	if err != nil {
 		return err
 	}
 
 	if err := os.RemoveAll(p); err != nil {
-		if os.IsNotExist(errors.Cause(err)) && action.AllowNotFound {
+		if os.IsNotExist(errors.Cause(err)) && allowNotFound {
 			return nil
 		}
 		return err

solver/pb/caps.go

@@ -46,6 +46,7 @@ const (
 	CapExecCgroupsMounted            apicaps.CapID = "exec.cgroup"
 
 	CapFileBase       apicaps.CapID = "file.base"
+	CapFileRmWildcard apicaps.CapID = "file.rm.wildcard"
 
 	CapConstraints apicaps.CapID = "constraints"
 	CapPlatform    apicaps.CapID = "platform"
@@ -252,6 +253,12 @@ func init() {
 		},
 	})
 
+	Caps.Init(apicaps.Cap{
+		ID:      CapFileRmWildcard,
+		Enabled: true,
+		Status:  apicaps.CapStatusExperimental,
+	})
+
 	Caps.Init(apicaps.Cap{
 		ID:      CapConstraints,
 		Enabled: true,