history: add export command

Allow builds to be exported into .dockerbuild bundles
that can be shared and imported into Docker Desktop.

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

util/desktop/bundle/trace.go

@@ -0,0 +1,76 @@
+package bundle
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"io"
+	"regexp"
+	"strings"
+
+	"github.com/containerd/containerd/v2/core/content"
+	"github.com/docker/buildx/util/otelutil"
+	"github.com/moby/buildkit/util/contentutil"
+	"github.com/opencontainers/go-digest"
+	ocispecs "github.com/opencontainers/image-spec/specs-go/v1"
+	"go.opentelemetry.io/otel/attribute"
+)
+
+var (
+	sensitiveKeys = []string{"ghtoken", "token", "access_key_id", "secret_access_key", "session_token"}
+	reAttrs       = regexp.MustCompile(`(?i)(` + strings.Join(sensitiveKeys, "|") + `)=[^ ,]+`)
+	reGhs         = regexp.MustCompile(`ghs_[A-Za-z0-9]{36}`)
+)
+
+func sanitizeCommand(value string) string {
+	value = reAttrs.ReplaceAllString(value, "${1}=xxxxx")
+	// reGhs is just double proofing. Not really needed.
+	value = reGhs.ReplaceAllString(value, "xxxxx")
+	return value
+}
+
+func sanitizeTrace(ctx context.Context, mp *contentutil.MultiProvider, desc ocispecs.Descriptor) (*ocispecs.Descriptor, error) {
+	ra, err := mp.ReaderAt(ctx, desc)
+	if err != nil {
+		return nil, err
+	}
+	defer ra.Close()
+
+	buf := &bytes.Buffer{}
+	dec := json.NewDecoder(io.NewSectionReader(ra, 0, ra.Size()))
+	enc := json.NewEncoder(buf)
+	enc.SetIndent("", "  ")
+	for {
+		var obj otelutil.Span
+		if err := dec.Decode(&obj); err == io.EOF {
+			break
+		} else if err != nil {
+			return nil, err
+		}
+
+		for i, att := range obj.Attributes {
+			v := att.Value
+			if v.Type() == attribute.STRING {
+				obj.Attributes[i].Value = attribute.StringValue(sanitizeCommand(v.AsString()))
+			}
+		}
+
+		if err := enc.Encode(obj); err != nil {
+			return nil, err
+		}
+	}
+
+	buffer := contentutil.NewBuffer()
+	newDesc := ocispecs.Descriptor{
+		MediaType: desc.MediaType,
+		Size:      int64(buf.Len()),
+		Digest:    digest.FromBytes(buf.Bytes()),
+	}
+	if err := content.WriteBlob(ctx, buffer, "trace-sanitized", bytes.NewReader(buf.Bytes()), newDesc); err != nil {
+		return nil, err
+	}
+
+	mp.Add(newDesc.Digest, buffer)
+
+	return &newDesc, nil
+}