Add nerdctl support

README.md

@@ -90,6 +90,7 @@ With valid `source` options as such:
 - `docker`: Docker engine (the default option)
 - `docker-archive`: A Docker Tar Archive from disk
 - `podman`: Podman engine (linux only)
+- `nerdctl`: Nerdctl engine
 
 ## Installation
 
@@ -246,7 +247,7 @@ Key Binding                                | Description
 
 No configuration is necessary, however, you can create a config file and override values:
 ```yaml
-# supported options are "docker" and "podman"
+# supported options are "docker", "podman" and "nerdctl"
 container-engine: docker
 # continue with analysis even if there are errors parsing the image archive
 ignore-errors: false

dive/get_image_resolver.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/wagoodman/dive/dive/image"
 	"github.com/wagoodman/dive/dive/image/docker"
+	"github.com/wagoodman/dive/dive/image/nerdctl"
 	"github.com/wagoodman/dive/dive/image/podman"
 )
 
@@ -15,14 +16,15 @@ const (
 	SourceDockerEngine
 	SourcePodmanEngine
 	SourceDockerArchive
+	SourceNerdctlEngine
 )
 
 type ImageSource int
 
-var ImageSources = []string{SourceDockerEngine.String(), SourcePodmanEngine.String(), SourceDockerArchive.String()}
+var ImageSources = []string{SourceDockerEngine.String(), SourcePodmanEngine.String(), SourceDockerArchive.String(), SourceNerdctlEngine.String()}
 
 func (r ImageSource) String() string {
-	return [...]string{"unknown", "docker", "podman", "docker-archive"}[r]
+	return [...]string{"unknown", "docker", "podman", "docker-archive", "nerdctl"}[r]
 }
 
 func ParseImageSource(r string) ImageSource {
@@ -33,6 +35,8 @@ func ParseImageSource(r string) ImageSource {
 		return SourcePodmanEngine
 	case SourceDockerArchive.String():
 		return SourceDockerArchive
+	case SourceNerdctlEngine.String():
+		return SourceNerdctlEngine
 	case "docker-tar":
 		return SourceDockerArchive
 	default:
@@ -53,6 +57,8 @@ func DeriveImageSource(image string) (ImageSource, string) {
 		return SourceDockerEngine, imageSource
 	case SourcePodmanEngine.String():
 		return SourcePodmanEngine, imageSource
+	case SourceNerdctlEngine.String():
+		return SourceNerdctlEngine, imageSource
 	case SourceDockerArchive.String():
 		return SourceDockerArchive, imageSource
 	case "docker-tar":
@@ -67,6 +73,8 @@ func GetImageResolver(r ImageSource) (image.Resolver, error) {
 		return docker.NewResolverFromEngine(), nil
 	case SourcePodmanEngine:
 		return podman.NewResolverFromEngine(), nil
+	case SourceNerdctlEngine:
+		return nerdctl.NewResolverFromEngine(), nil
 	case SourceDockerArchive:
 		return docker.NewResolverFromArchive(), nil
 	}

dive/image/nerdctl/build.go

@@ -0,0 +1,26 @@
+package nerdctl
+
+import (
+	"os"
+)
+
+func buildImageFromCli(buildArgs []string) (string, error) {
+	iidfile, err := os.CreateTemp("/tmp", "dive.*.iid")
+	if err != nil {
+		return "", err
+	}
+	defer os.Remove(iidfile.Name())
+
+	allArgs := append([]string{"--iidfile", iidfile.Name()}, buildArgs...)
+	err = runNerdctlCmd("build", allArgs...)
+	if err != nil {
+		return "", err
+	}
+
+	imageId, err := os.ReadFile(iidfile.Name())
+	if err != nil {
+		return "", err
+	}
+
+	return string(imageId), nil
+}

dive/image/nerdctl/cli.go

@@ -0,0 +1,54 @@
+package nerdctl
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+
+	"github.com/wagoodman/dive/utils"
+)
+
+// runNerdctlCmd runs a given nerdctl command in the current tty
+func runNerdctlCmd(cmdStr string, args ...string) error {
+	if !isNerdctlBinaryAvailable() {
+		return fmt.Errorf("cannot find nerdctl executable")
+	}
+
+	allArgs := utils.CleanArgs(append([]string{cmdStr}, args...))
+
+	cmd := exec.Command("nerdctl", allArgs...)
+	cmd.Env = os.Environ()
+
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	cmd.Stdin = os.Stdin
+
+	return cmd.Run()
+}
+
+func streamNerdctlCmd(args ...string) (io.Reader, error) {
+	if !isNerdctlBinaryAvailable() {
+		return nil, fmt.Errorf("cannot find nerdctl executable")
+	}
+
+	cmd := exec.Command("nerdctl", utils.CleanArgs(args)...)
+	cmd.Env = os.Environ()
+
+	reader, writer, err := os.Pipe()
+	if err != nil {
+		return nil, err
+	}
+
+	defer writer.Close()
+
+	cmd.Stdout = writer
+	cmd.Stderr = os.Stderr
+
+	return reader, cmd.Start()
+}
+
+func isNerdctlBinaryAvailable() bool {
+	_, err := exec.LookPath("nerdctl")
+	return err == nil
+}

dive/image/nerdctl/resolver.go

@@ -0,0 +1,68 @@
+package nerdctl
+
+import (
+	"fmt"
+	"io"
+
+	"github.com/wagoodman/dive/dive/image"
+	"github.com/wagoodman/dive/dive/image/docker"
+)
+
+type resolver struct{}
+
+func NewResolverFromEngine() *resolver {
+	return &resolver{}
+}
+
+func (r *resolver) Build(args []string) (*image.Image, error) {
+	id, err := buildImageFromCli(args)
+
+	if err != nil {
+		return nil, err
+	}
+
+	return r.Fetch(id)
+}
+
+func (r *resolver) Fetch(id string) (*image.Image, error) {
+	img, err := r.resolveFromDockerArchive(id)
+
+	if err == nil {
+		return img, err
+	}
+
+	return nil, fmt.Errorf("unable to resolve image '%s': %+v", id, err)
+}
+
+func (r *resolver) resolveFromDockerArchive(id string) (*image.Image, error) {
+	reader, err := streamNerdctlCmd("image", "save", id)
+
+	if err != nil {
+		return nil, err
+	}
+
+	img, err := docker.NewImageArchive(io.NopCloser(reader))
+
+	if err != nil {
+		fmt.Println("Handler not available locally. Trying to pull '" + id + "'...")
+		err = runNerdctlCmd("pull", id)
+
+		if err != nil {
+			return nil, err
+		}
+
+		reader, err = streamNerdctlCmd("image", "save", id)
+
+		if err != nil {
+			return nil, err
+		}
+
+		img, err = docker.NewImageArchive(io.NopCloser(reader))
+
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return img.ToImage()
+}