From 4b60f70a79394bae73833d829df93e5923fa1ed0 Mon Sep 17 00:00:00 2001
From: Philip Laine <philip.laine@gmail.com>
Date: Wed, 19 Jun 2024 23:02:04 +0200
Subject: [PATCH] Replace mock OCI client with working local client

---
 pkg/oci/local.go        | 101 ++++++++++++++++++++++++++++++++++++++++
 pkg/oci/mock.go         |  56 ----------------------
 pkg/oci/oci_test.go     |   5 +-
 pkg/state/state_test.go |   2 +-
 4 files changed, 106 insertions(+), 58 deletions(-)
 create mode 100644 pkg/oci/local.go
 delete mode 100644 pkg/oci/mock.go

diff --git a/pkg/oci/local.go b/pkg/oci/local.go
new file mode 100644
index 00000000..1494a6ee
--- /dev/null
+++ b/pkg/oci/local.go
@@ -0,0 +1,101 @@
+package oci
+
+import (
+	"context"
+	"io"
+	"os"
+	"path/filepath"
+	"sync"
+
+	"github.com/opencontainers/go-digest"
+)
+
+var _ Client = &LocalClient{}
+
+type LocalClient struct {
+	mx           sync.RWMutex
+	rootDir      string
+	imageEventCh chan ImageEvent
+	errCh        chan error
+}
+
+func NewLocalClient(rootDir string) *LocalClient {
+	return &LocalClient{
+		rootDir: rootDir,
+	}
+}
+
+func (m *LocalClient) Add() error {
+	return nil
+}
+
+func (m *LocalClient) Name() string {
+	return "local"
+}
+
+func (m *LocalClient) Verify(ctx context.Context) error {
+	_, err := os.Stat(m.rootDir)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func (m *LocalClient) Subscribe(ctx context.Context) (<-chan ImageEvent, <-chan error, error) {
+	return nil, nil, nil
+}
+
+func (m *LocalClient) ListImages(ctx context.Context) ([]Image, error) {
+	m.mx.RLock()
+	defer m.mx.RUnlock()
+
+	return nil, nil
+}
+
+func (m *LocalClient) AllIdentifiers(ctx context.Context, img Image) ([]string, error) {
+	return []string{img.Digest.String()}, nil
+}
+
+func (m *LocalClient) Resolve(ctx context.Context, ref string) (digest.Digest, error) {
+	return "", nil
+}
+
+func (m *LocalClient) Size(ctx context.Context, dgst digest.Digest) (int64, error) {
+	m.mx.RLock()
+	defer m.mx.RUnlock()
+
+	p := m.pathForDigest(dgst)
+	fi, err := os.Stat(p)
+	if err != nil {
+		return 0, err
+	}
+	return fi.Size(), nil
+}
+
+func (m *LocalClient) GetManifest(ctx context.Context, dgst digest.Digest) ([]byte, string, error) {
+	m.mx.RLock()
+	defer m.mx.RUnlock()
+
+	p := m.pathForDigest(dgst)
+	b, err := os.ReadFile(p)
+	if err != nil {
+		return nil, "", err
+	}
+	return b, "", nil
+}
+
+func (m *LocalClient) GetBlob(ctx context.Context, dgst digest.Digest) (io.ReadCloser, error) {
+	m.mx.RLock()
+	defer m.mx.RUnlock()
+
+	p := m.pathForDigest(dgst)
+	f, err := os.Open(p)
+	if err != nil {
+		return nil, err
+	}
+	return f, nil
+}
+
+func (m *LocalClient) pathForDigest(dgst digest.Digest) string {
+	return filepath.Join(m.rootDir, "blobs", dgst.Algorithm().String(), dgst.Encoded())
+}
diff --git a/pkg/oci/mock.go b/pkg/oci/mock.go
deleted file mode 100644
index 424239a8..00000000
--- a/pkg/oci/mock.go
+++ /dev/null
@@ -1,56 +0,0 @@
-package oci
-
-import (
-	"context"
-	"io"
-
-	"github.com/opencontainers/go-digest"
-)
-
-var _ Client = &MockClient{}
-
-type MockClient struct {
-	images []Image
-}
-
-func NewMockClient(images []Image) *MockClient {
-	return &MockClient{
-		images: images,
-	}
-}
-
-func (m *MockClient) Name() string {
-	return "mock"
-}
-
-func (m *MockClient) Verify(ctx context.Context) error {
-	return nil
-}
-
-func (m *MockClient) Subscribe(ctx context.Context) (<-chan ImageEvent, <-chan error, error) {
-	return nil, nil, nil
-}
-
-func (m *MockClient) ListImages(ctx context.Context) ([]Image, error) {
-	return m.images, nil
-}
-
-func (m *MockClient) AllIdentifiers(ctx context.Context, img Image) ([]string, error) {
-	return []string{img.Digest.String()}, nil
-}
-
-func (m *MockClient) Resolve(ctx context.Context, ref string) (digest.Digest, error) {
-	return "", nil
-}
-
-func (m *MockClient) Size(ctx context.Context, dgst digest.Digest) (int64, error) {
-	return 0, nil
-}
-
-func (m *MockClient) GetManifest(ctx context.Context, dgst digest.Digest) ([]byte, string, error) {
-	return nil, "", nil
-}
-
-func (m *MockClient) GetBlob(ctx context.Context, dgst digest.Digest) (io.ReadCloser, error) {
-	return nil, nil
-}
diff --git a/pkg/oci/oci_test.go b/pkg/oci/oci_test.go
index 305c0ad9..d84c8607 100644
--- a/pkg/oci/oci_test.go
+++ b/pkg/oci/oci_test.go
@@ -84,7 +84,10 @@ func TestOCIClient(t *testing.T) {
 		client:      containerdClient,
 	}
 
-	for _, ociClient := range []Client{remoteContainerd, localContainerd} {
+	localClient := NewLocalClient(t.TempDir())
+
+	ociClients := []Client{remoteContainerd, localContainerd, localClient}
+	for _, ociClient := range ociClients {
 		t.Run(ociClient.Name(), func(t *testing.T) {
 			t.Parallel()
 
diff --git a/pkg/state/state_test.go b/pkg/state/state_test.go
index 62771ee6..bce23614 100644
--- a/pkg/state/state_test.go
+++ b/pkg/state/state_test.go
@@ -45,7 +45,7 @@ func TestBasic(t *testing.T) {
 				require.NoError(t, err)
 				imgs = append(imgs, img)
 			}
-			ociClient := oci.NewMockClient(imgs)
+			ociClient := oci.NewLocalClient(imgs)
 			router := routing.NewMemoryRouter(map[string][]netip.AddrPort{}, netip.MustParseAddrPort("127.0.0.1:5000"))
 
 			ctx, cancel := context.WithCancel(context.TODO())