[Issue 3759] Support direct buildkit builds without requiring a docke…

…r daemon on the build host

internal/pipe/dockerbuildkit/api.go

@@ -0,0 +1,145 @@
+package buildkit
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"regexp"
+	"strings"
+
+	"github.com/caarlos0/log"
+	"github.com/goreleaser/goreleaser/internal/gio"
+	"github.com/goreleaser/goreleaser/internal/logext"
+	"github.com/goreleaser/goreleaser/pkg/config"
+	"github.com/goreleaser/goreleaser/pkg/context"
+)
+
+// nolint: unparam
+func runCommand(ctx *context.Context, dir, binary string, args ...string) error {
+	/* #nosec */
+	cmd := exec.CommandContext(ctx, binary, args...)
+	cmd.Dir = dir
+	cmd.Env = append(ctx.Env.Strings(), cmd.Environ()...)
+
+	var b bytes.Buffer
+	w := gio.Safe(&b)
+	cmd.Stderr = io.MultiWriter(logext.NewWriter(), w)
+	cmd.Stdout = io.MultiWriter(logext.NewWriter(), w)
+
+	log.
+		WithField("cmd", append([]string{binary}, args[0])).
+		WithField("cwd", dir).
+		WithField("args", args[1:]).Debug("running")
+	if err := cmd.Run(); err != nil {
+		return fmt.Errorf("%w: %s", err, b.String())
+	}
+	return nil
+}
+
+func runCommandWithOutput(ctx *context.Context, dir, binary string, args ...string) ([]byte, error) {
+	/* #nosec */
+	cmd := exec.CommandContext(ctx, binary, args...)
+	cmd.Dir = dir
+	cmd.Env = append(ctx.Env.Strings(), cmd.Environ()...)
+
+	var b bytes.Buffer
+	w := gio.Safe(&b)
+
+	log.
+		WithField("cmd", append([]string{binary}, args[0])).
+		WithField("cwd", dir).
+		WithField("args", args[1:]).
+		Debug("running")
+	out, err := cmd.CombinedOutput()
+	if out != nil {
+		// regardless of command success, always print stdout for backward-compatibility with runCommand()
+		_, _ = io.MultiWriter(logext.NewWriter(), w).Write(out)
+	}
+	if err != nil {
+		return nil, fmt.Errorf("%w: %s", err, b.String())
+	}
+
+	return out, nil
+}
+
+var dockerBuildDigestPattern = regexp.MustCompile("writing image (sha256:[a-z0-9]{64})")
+
+func build(ctx *context.Context, root string, images, buildFlags []string, builder string, platforms []config.DockerPlatform, loadImages bool) (string, error) {
+	command := buildCommand(root, images, buildFlags, builder, platforms, loadImages)
+	out, err := runCommandWithOutput(ctx, root, "docker", command...)
+	if err != nil {
+		return "", fmt.Errorf("failed to build %s: %w", images[0], err)
+	}
+	if !loadImages {
+		return "", nil
+	}
+	digest := dockerBuildDigestPattern.FindStringSubmatch(string(out))
+	if len(digest) < 2 {
+		return "", fmt.Errorf("failed to find docker digest in docker build output: %s", string(out))
+	}
+	return digest[1], nil
+}
+
+type metadataFile struct {
+	ImageName            string `json:"image.name"` // DEPRECATED: inconsistent support in BuildKit.
+	ContainerImageDigest string `json:"containerimage.digest"`
+}
+
+func push(ctx *context.Context, root string, images, flags []string, builder string, platforms []config.DockerPlatform) (string, error) {
+	command := pushCommand(root, images, flags, builder, platforms)
+	err := runCommand(ctx, root, "docker", command...)
+	if err != nil {
+		return "", fmt.Errorf("failed to build %s: %w", images[0], err)
+	}
+	// Retrieve the manifest digest from the metadata file produced during the build
+	content, err := os.OpenFile(root+"/metadata.json", os.O_RDONLY, os.ModePerm)
+	if err != nil {
+		return "", fmt.Errorf("failed to find docker digest in docker build output: %w", err)
+	}
+	defer content.Close()
+	output, err := io.ReadAll(content)
+	if err != nil {
+		return "", fmt.Errorf("failed to find docker digest in docker build output: %w", err)
+	}
+	metadata := metadataFile{}
+	if err := json.Unmarshal(output, &metadata); err != nil {
+		return "", fmt.Errorf("failed to find docker digest in docker build output: %w", err)
+	}
+	return metadata.ContainerImageDigest, nil
+}
+
+func baseCommand(root string, images, flags []string, platforms []config.DockerPlatform, builderName string) []string {
+	cmd := []string{"buildx"}
+	if builderName != "" {
+		cmd = append(cmd, "--builder", builderName)
+	}
+	cmd = append(cmd, "build", ".")
+	platformNames := []string{}
+	for _, platform := range platforms {
+		platformNames = append(platformNames, fmt.Sprintf("%s/%s", platform.Os, platform.Arch))
+	}
+	cmd = append(cmd, "--platform", strings.Join(platformNames, ","))
+	for _, image := range images {
+		cmd = append(cmd, "-t", image)
+	}
+	cmd = append(cmd, flags...)
+	return cmd
+}
+
+func buildCommand(root string, images, buildFlags []string, builder string, platforms []config.DockerPlatform, loadImages bool) []string {
+	cmd := baseCommand(root, images, buildFlags, platforms, builder)
+	if loadImages {
+		cmd = append(cmd, "--load")
+	}
+	return cmd
+}
+
+func pushCommand(root string, images, buildAndPushFlags []string, builder string, platforms []config.DockerPlatform) []string {
+	cmd := baseCommand(root, images, buildAndPushFlags, platforms, builder)
+	cmd = append(cmd, "--push")
+	cmd = append(cmd, "--metadata-file", root+"/metadata.json")
+	return cmd
+}