Merge pull request #53 from robnester-rh/EC-486

EC-486 Add initial oci/oras support

common.go

@@ -32,14 +32,15 @@ const (
 	GitURI URIType = iota
 	HTTPURI
 	FileURI
+	OCIURI
 	Unknown
 )
 
 var getHomeDir = os.UserHomeDir
 
 // String returns the string representation of the URLType
 func (t URIType) String() string {
-	return [...]string{"GitURI", "HTTPURI", "FileURI", "Unknown"}[t]
+	return [...]string{"GitURI", "HTTPURI", "FileURI", "OCIURL", "Unknown"}[t]
 }
 
 // ExpandTilde expands a leading tilde in the file path to the user's home directory
@@ -67,6 +68,10 @@ func ClassifyURI(input string) (URIType, error) {
 		return HTTPURI, nil
 	}
 
+	if strings.HasPrefix(input, "oci::") {
+		return OCIURI, nil
+	}
+
 	if strings.HasPrefix(input, "github.com") || strings.HasPrefix(input, "gitlab.com") {
 		return GitURI, nil
 	}
@@ -77,6 +82,9 @@ func ClassifyURI(input string) (URIType, error) {
 	httpURIPattern := regexp.MustCompile(`^((http://|https://)[\w\-]+(\.[\w\-]+)+.*)$`)
 	// Regular expression for file paths
 	filePathPattern := regexp.MustCompile(`^(\./|\../|/|[a-zA-Z]:\\|~\/|file://).*`)
+	// Regular expression for OCI URIs
+	ociURIPattern := regexp.MustCompile(`^((oci://)[\w\-]+(\.[\w\-]+)+.*)$`)
+	// Regular expressions for known OCI registries
 
 	// Check if the input matches the file path pattern first
 	if filePathPattern.MatchString(input) {
@@ -103,6 +111,17 @@ func ClassifyURI(input string) (URIType, error) {
 		}
 	}
 
+	// Check if the input matches the OCI URI pattern
+	if ociURIPattern.MatchString(input) {
+		return OCIURI, nil
+	}
+
+	// Check if the input matches any known OCI registry
+	isOCI := containsOCIRegistry(input)
+	if isOCI {
+		return OCIURI, nil
+	}
+
 	// Check for unsupported schemes
 	parsedURI, err := url.Parse(input)
 	if err == nil && parsedURI.Scheme != "" && parsedURI.Scheme != "http" && parsedURI.Scheme != "https" {
@@ -131,3 +150,23 @@ func ValidateFileDestination(destination string) error {
 	}
 	return nil
 }
+
+// containsOCIRegistry checks if the input string contains a known OCI registry
+func containsOCIRegistry(src string) bool {
+	matchRegistries := []*regexp.Regexp{
+		regexp.MustCompile("azurecr.io"),
+		regexp.MustCompile("gcr.io"),
+		regexp.MustCompile("registry.gitlab.com"),
+		regexp.MustCompile("pkg.dev"),
+		regexp.MustCompile("[0-9]{12}.dkr.ecr.[a-z0-9-]*.amazonaws.com"),
+		regexp.MustCompile("^quay.io"),
+		regexp.MustCompile(`(?:::1|127\.0\.0\.1|(?i:localhost)):\d{1,5}`), // localhost OCI registry
+	}
+
+	for _, matchRegistry := range matchRegistries {
+		if matchRegistry.MatchString(src) {
+			return true
+		}
+	}
+	return false
+}

common_test.go

@@ -97,6 +97,17 @@ func TestClassifyURI(t *testing.T) {
 		{input: "ftpexamplecom", expected: Unknown},
 		{input: "github.com/user/repo.git", expected: GitURI},
 		{input: "gitlab.com/user/repo.git", expected: GitURI},
+		{input: "oci::registry.gitlab.com/user/repo:latest", expected: OCIURI},
+		{input: "oci::registry.gitlab.com/user/repo", expected: OCIURI},
+		{input: "oci::registry.gitlab.com/user/repo:1.0.0", expected: OCIURI},
+		{input: "oci://example.org/user/repo:latest", expected: OCIURI},
+		{input: "quay.io/user/repo:latest", expected: OCIURI},
+		{input: "127.0.0.1:5000", expected: OCIURI},
+		{input: "registry.gitlab.com/user/repo:latest", expected: OCIURI},
+		{input: "pkg.dev/user/repo:latest", expected: OCIURI},
+		{input: "123456789012.dkr.ecr.us-west-2.amazonaws.com/user/repo:latest", expected: OCIURI},
+		{input: "gcr.io/user/repo:latest", expected: OCIURI},
+		{input: "azurecr.io/user/repo:latest", expected: OCIURI},
 	}
 
 	for _, tc := range testCases {
@@ -184,3 +195,30 @@ func TestValidateFileDestination_errors(t *testing.T) {
 		os.RemoveAll(dir)
 	})
 }
+
+func TestContainsOCIRegistry(t *testing.T) {
+	testCases := []struct {
+		input    string
+		expected bool
+	}{
+		{input: "azurecr.io", expected: true},
+		{input: "gcr.io", expected: true},
+		{input: "registry.gitlab.com", expected: true},
+		{input: "pkg.dev", expected: true},
+		{input: "123456789012.dkr.ecr.us-west-2.amazonaws.com", expected: true},
+		{input: "quay.io", expected: true},
+		{input: "::1", expected: false},
+		{input: "127.0.0.1", expected: false},
+		{input: "123.123.123.123", expected: false},
+		{input: "127.0.0.1:8080", expected: true},
+		{input: "localhost:8080", expected: true},
+		{input: "example.com", expected: false},
+	}
+
+	for _, tc := range testCases {
+		actual := containsOCIRegistry(tc.input)
+		if actual != tc.expected {
+			t.Errorf("Expected containsOCIRegistry(%s) to return %t, but got %t", tc.input, tc.expected, actual)
+		}
+	}
+}

gather/gather.go

@@ -28,6 +28,7 @@ import (
 	"github.com/enterprise-contract/go-gather/gather/file"
 	"github.com/enterprise-contract/go-gather/gather/git"
 	"github.com/enterprise-contract/go-gather/gather/http"
+	"github.com/enterprise-contract/go-gather/gather/oci"
 	"github.com/enterprise-contract/go-gather/metadata"
 )
 
@@ -41,6 +42,7 @@ var protocolHandlers = map[string]Gatherer{
 	"FileURI": &file.FileGatherer{},
 	"GitURI":  &git.GitGatherer{},
 	"HTTPURI": &http.HTTPGatherer{},
+	"OCIURI": &oci.OCIGatherer{},
 }
 
 // Gather determines the protocol from the source URI and uses the appropriate Gatherer to perform the operation.

gather/gather_test.go

@@ -32,7 +32,7 @@ func TestGather(t *testing.T) {
 	ctx := context.Background()
 	t.Run("SourceParseError", func(t *testing.T) {
 		source := ":"
-		destination := "/path/to/destination"
+		destination := "/tmp/foo"
 
 		_, err := Gather(ctx, source, destination)
 		if err == nil {
@@ -43,11 +43,14 @@ func TestGather(t *testing.T) {
 		if err.Error() != expectedErrorMessage {
 			t.Errorf("expected error message: %s, but got: %s", expectedErrorMessage, err.Error())
 		}
+		t.Cleanup(func() {
+			os.RemoveAll(destination)
+		})
 	})
 
 	t.Run("UnsupportedProtocol", func(t *testing.T) {
 		source := "ftp://example.com/file.txt"
-		destination := "/path/to/destination"
+		destination := "/tmp/foo"
 		defer os.RemoveAll(destination)
 
 		_, err := Gather(ctx, source, destination)
@@ -66,7 +69,7 @@ func TestGather(t *testing.T) {
 
 	t.Run("SupportedProtocol_git", func(t *testing.T) {
 		source := "git::https://github.com/git-fixtures/basic.git"
-		destination := "/tmp/path/to/destination"
+		destination := "/tmp/foo"
 		defer os.RemoveAll(destination)
 
 		_, err := Gather(ctx, source, destination)
@@ -91,6 +94,9 @@ func TestGather(t *testing.T) {
 		if err != nil {
 			t.Errorf("expected no error, but got: %s", err.Error())
 		}
+		t.Cleanup(func() {
+			os.RemoveAll(destination)
+		})
 	})
 
 	t.Run("CustomGatherer", func(t *testing.T) {
@@ -102,6 +108,9 @@ func TestGather(t *testing.T) {
 		if err != nil {
 			t.Errorf("expected no error, but got: %s", err.Error())
 		}
+		t.Cleanup(func() {
+			os.RemoveAll(destination)
+		})
 	})
 }
 

gather/go.mod

@@ -7,6 +7,7 @@ require (
 	github.com/enterprise-contract/go-gather/gather/file v0.0.1
 	github.com/enterprise-contract/go-gather/gather/git v0.0.1
 	github.com/enterprise-contract/go-gather/gather/http v0.0.1
+	github.com/enterprise-contract/go-gather/gather/oci v0.0.1
 	github.com/enterprise-contract/go-gather/metadata v0.0.1
 	github.com/enterprise-contract/go-gather/metadata/git v0.0.1
 )

gather/oci/go.mod

@@ -0,0 +1,39 @@
+module github.com/enterprise-contract/go-gather/gather/oci
+
+go 1.21.9
+
+require (
+	github.com/open-policy-agent/conftest v0.53.0
+	oras.land/oras-go/v2 v2.5.0
+
+	github.com/enterprise-contract/go-gather/metadata/oci v0.0.1
+)
+
+require (
+	github.com/fsnotify/fsnotify v1.7.0 // indirect
+	github.com/google/go-containerregistry v0.19.2
+	github.com/hashicorp/hcl v1.0.0 // indirect
+	github.com/magiconair/properties v1.8.7 // indirect
+	github.com/mitchellh/mapstructure v1.5.0 // indirect
+	github.com/opencontainers/go-digest v1.0.0 // indirect
+	github.com/opencontainers/image-spec v1.1.0 // indirect
+	github.com/pelletier/go-toml/v2 v2.2.2 // indirect
+	github.com/rogpeppe/go-internal v1.12.0 // indirect
+	github.com/sagikazarmark/locafero v0.4.0 // indirect
+	github.com/sagikazarmark/slog-shim v0.1.0 // indirect
+	github.com/sourcegraph/conc v0.3.0 // indirect
+	github.com/spf13/afero v1.11.0 // indirect
+	github.com/spf13/cast v1.6.0 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
+	github.com/spf13/viper v1.18.2 // indirect
+	github.com/subosito/gotenv v1.6.0 // indirect
+	go.uber.org/atomic v1.9.0 // indirect
+	go.uber.org/multierr v1.9.0 // indirect
+	golang.org/x/exp v0.0.0-20231006140011-7918f672742d // indirect
+	golang.org/x/sync v0.7.0 // indirect
+	golang.org/x/sys v0.21.0 // indirect
+	golang.org/x/text v0.16.0 // indirect
+	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect
+	gopkg.in/ini.v1 v1.67.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

gather/oci/go.sum

@@ -0,0 +1,80 @@
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+github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
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+gopkg.in/ini.v1 v1.67.0/go.mod h1:pNLf8WUiyNEtQjuu5G5vTm06TEv9tsIgeAvK8hOrP4k=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+oras.land/oras-go/v2 v2.5.0 h1:o8Me9kLY74Vp5uw07QXPiitjsw7qNXi8Twd+19Zf02c=
+oras.land/oras-go/v2 v2.5.0/go.mod h1:z4eisnLP530vwIOUOJeBIj0aGI0L1C3d53atvCBqZHg=

gather/oci/internal/network/network.go

@@ -0,0 +1,45 @@
+package network
+
+import (
+	"net"
+	"strings"
+)
+
+/* This code is sourced from the open-policy-agent/conftest project. */
+func Hostname(ref string) string {
+	ref = strings.TrimPrefix(ref, "oci://")
+
+	colon := strings.Index(ref, ":")
+	slash := strings.Index(ref, "/")
+
+	cut := colon
+	if colon == -1 || (colon > slash && slash != -1) {
+		cut = slash
+	}
+
+	if cut < 0 {
+		return ref
+	}
+
+	return ref[0:cut]
+}
+
+func IsLoopback(host string) bool {
+	if host == "localhost" || host == "127.0.0.1" || host == "::1" || host == "0:0:0:0:0:0:0:1" {
+		// fast path
+		return true
+	}
+
+	ips, err := net.LookupIP(host)
+	if err != nil {
+		return false
+	}
+
+	for _, ip := range ips {
+		if ip.IsLoopback() {
+			return true
+		}
+	}
+
+	return false
+}