support running tests as non-root

also, just go down to latest released buildkit instead of building from
master, since building it is too complicated to do in a task (requires
docker) and the reason for needing it is kind of questionable in the
first place

Signed-off-by: Alex Suraci <suraci.alex@gmail.com>

.gitignore

@@ -3,3 +3,6 @@ scripts/.tests
 bin/buildctl
 bin/buildkitd
 bin/buildkit-runc
+bin/rootlessctl
+bin/rootlesskit
+bin/rootlesskit-docker-proxy

.gitmodules

@@ -1,3 +1,3 @@
-[submodule "buildkit"]
-	path = buildkit
-	url = https://github.com/moby/buildkit
+[submodule "rootlesskit"]
+	path = rootlesskit
+	url = https://github.com/rootless-containers/rootlesskit

scripts/test

@@ -1,24 +1,29 @@
 #!/bin/bash
 
-set -e -u -x
+set -e -u
 
 cd $(dirname $0)/..
 
 if ! [ -e bin/buildctl ] || ! [ -e bin/buildkitd ]; then
-  dest=$(pwd)
-  pushd buildkit
-    make
-    make DESTDIR=$dest install
-  popd
-
-  # once a new version of buildkit is out, remove the submodule and do the
-  # following instead
-  #
-  # BUILDKIT_VERSION=0.6.1
-  # BUILDKIT_URL=https://github.com/moby/buildkit/releases/download/v$BUILDKIT_VERSION/buildkit-v$BUILDKIT_VERSION.linux-amd64.tar.gz
-
-  # curl -fsSL "$BUILDKIT_URL" | tar zxf -
+  BUILDKIT_VERSION=0.6.1
+  BUILDKIT_URL=https://github.com/moby/buildkit/releases/download/v$BUILDKIT_VERSION/buildkit-v$BUILDKIT_VERSION.linux-amd64.tar.gz
+
+  curl -fL "$BUILDKIT_URL" | tar zxf -
+fi
+
+if [ "$(id -u)" != "0" ]; then
+  if ! which newuidmap >/dev/null || ! which newgidmap >/dev/null; then
+    echo "newuidmap and newgidmap must be installed"
+    exit 1
+  fi
+
+  if ! [ -e bin/rootlesskit ]; then
+    pushd rootlesskit
+      make
+    popd
+
+    cp rootlesskit/bin/* bin/
+  fi
 fi
 
-go test -c -o scripts/.tests
-sudo scripts/.tests "$@"
+go test "$@"

task.go

@@ -18,7 +18,6 @@ import (
 	"github.com/concourse/go-archive/tarfs"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/layout"
-	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
@@ -78,7 +77,7 @@ func Build(rootPath string, req Request) (Response, error) {
 	if _, err := os.Stat(imageDir); err == nil {
 		ociImagePath = filepath.Join(imageDir, "image.tar")
 		buildctlArgs = append(buildctlArgs,
-			"--output", "type=oci,name="+cfg.ImageName()+",dest="+ociImagePath,
+			"--output", "type=oci,dest="+ociImagePath,
 		)
 	}
 
@@ -153,9 +152,12 @@ func unpackRootfs(dest string, ociImagePath string, cfg Config) error {
 			}
 		}
 
-		if m.Annotations != nil && m.Annotations[ocispec.AnnotationRefName] != cfg.Tag {
-			continue
-		}
+		// TODO: is this even a sensible approach?
+		//
+		// note: depends on newer buildkit with support for named oci output
+		// if m.Annotations != nil && m.Annotations[ocispec.AnnotationRefName] != cfg.Tag {
+		// 	continue
+		// }
 
 		if unpacked != "" {
 			logrus.WithFields(logrus.Fields{