✨ [filesystem] Support for ZipFS (#292)

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Copyright (C) 2020-2022 Arm Limited or its affiliates and Contributors.
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### Description

- Added support for  `ZipFS`



### Test Coverage

<!--
Please put an `x` in the correct box e.g. `[x]` to indicate the testing
coverage of this change.
-->

- [x]  This change is covered by existing or additional automated tests.
- [ ] Manual testing has been performed (and evidence provided) as
automated testing was not feasible.
- [ ] Additional tests are not required for this change (e.g.
documentation update).

changes/20230724173139.feature

@@ -0,0 +1 @@
+:sparkles: `[errortest]` Added utilities to check the error description

changes/20230724173259.bugfix

@@ -0,0 +1 @@
+:recycle: `[filesystem]` Use `afero.ReadOnlyFS` rather than our own implementation when exposing `embed.FS`

changes/20230728174153.feature

@@ -0,0 +1 @@
+:sparkles: `[filesystem]` Added zipFS to enable filesystem utilities on zip files

changes/20230731170709.feature

@@ -0,0 +1 @@
+:sparkles: Added module `[resource]` to define generic utilities regarding resource management

utils/commonerrors/errortest/testing.go

@@ -18,6 +18,15 @@ func AssertError(t *testing.T, err error, expectedErrors ...error) bool {
 	return assert.Fail(t, fmt.Sprintf("Failed error assertion:\n actual: %v\n expected: %+v", err, expectedErrors))
 }
 
+// AssertErrorDescription asserts that the error description corresponds to one of the `expectedErrorDescriptions`
+// This is a wrapper for commonerrors.CorrespondTo.
+func AssertErrorDescription(t *testing.T, err error, expectedErrorDescriptions ...string) bool {
+	if commonerrors.CorrespondTo(err, expectedErrorDescriptions...) {
+		return true
+	}
+	return assert.Fail(t, fmt.Sprintf("Failed error description assertion:\n actual: %v\n expected: %+v", err, expectedErrorDescriptions))
+}
+
 // RequireError requires that the error is matching one of the `expectedErrors`
 // This is a wrapper for commonerrors.Any.
 func RequireError(t *testing.T, err error, expectedErrors ...error) {
@@ -27,3 +36,13 @@ func RequireError(t *testing.T, err error, expectedErrors ...error) {
 	}
 	t.FailNow()
 }
+
+// RequireErrorDescription requires that the error description corresponds to one of the `expectedErrorDescriptions`
+// This is a wrapper for commonerrors.CorrespondTo.
+func RequireErrorDescription(t *testing.T, err error, expectedErrorDescriptions ...string) {
+	t.Helper()
+	if commonerrors.CorrespondTo(err, expectedErrorDescriptions...) {
+		return
+	}
+	t.FailNow()
+}

utils/commonerrors/errortest/testing_test.go

@@ -10,6 +10,14 @@ func TestAssertError(t *testing.T) {
 	AssertError(t, commonerrors.ErrUndefined, commonerrors.ErrNotFound, commonerrors.ErrMarshalling, commonerrors.ErrUndefined)
 }
 
+func TestAssertErrorDescription(t *testing.T) {
+	AssertErrorDescription(t, commonerrors.ErrUndefined, "undefined", "not found")
+}
+
 func TestRequireError(t *testing.T) {
 	RequireError(t, commonerrors.ErrUndefined, commonerrors.ErrNotFound, commonerrors.ErrMarshalling, commonerrors.ErrUndefined)
 }
+
+func TestRequireErrorContent(t *testing.T) {
+	RequireErrorDescription(t, commonerrors.ErrUndefined, "undefined", "not found")
+}

utils/filesystem/embedfs.go

@@ -3,31 +3,17 @@ package filesystem
 import (
 	"embed"
 	"fmt"
-	"os"
 
 	"github.com/spf13/afero"
 
 	"github.com/ARM-software/golang-utils/utils/commonerrors"
 )
 
-type embedFsAdapter struct {
-	afero.Fs
-}
-
-func (e *embedFsAdapter) OpenFile(name string, flag int, _ os.FileMode) (afero.File, error) {
-	if flag != os.O_RDONLY {
-		return nil, fmt.Errorf("%w: embed.FS is readonly", commonerrors.ErrUnsupported)
-	}
-	return e.Open(name)
-}
-
 func newEmbedFSAdapter(fs *embed.FS) (afero.Fs, error) {
 	if fs == nil {
 		return nil, fmt.Errorf("%w: missing filesystem", commonerrors.ErrUndefined)
 	}
-	return &embedFsAdapter{
-		Fs: afero.FromIOFS{
-			FS: *fs,
-		},
-	}, nil
+	return afero.NewReadOnlyFs(afero.FromIOFS{
+		FS: *fs,
+	}), nil
 }

utils/filesystem/embedfs_test.go

@@ -137,7 +137,7 @@ func Test_embed_not_supported(t *testing.T) {
 	require.NoError(t, err)
 
 	_, err = efs.TempDir("testdata", "aaaa")
-	assert.True(t, commonerrors.CorrespondTo(err, "permission denied"))
+	errortest.AssertErrorDescription(t, err, "operation not permitted")
 
 	f, err := efs.OpenFile("testdata/embed/test.txt", os.O_RDWR, os.FileMode(0600))
 	defer func() {
@@ -146,10 +146,10 @@ func Test_embed_not_supported(t *testing.T) {
 		}
 	}()
 	require.Error(t, err)
-	errortest.AssertError(t, err, commonerrors.ErrUnsupported)
+	errortest.AssertErrorDescription(t, err, "operation not permitted")
 
 	err = efs.Chmod("testdata/embed/test.txt", os.FileMode(0600))
 	require.Error(t, err)
-	assert.True(t, commonerrors.CorrespondTo(err, "permission denied"))
+	errortest.AssertErrorDescription(t, err, "operation not permitted")
 
 }