initial testing infrastructure

* tests run as root, directly on the host
  * can't really find a good way around this
  * at one point i had the tests build + run the task with the docker
    CLI, with some ugly volume mount shenanigans, but assertions need to
    be made against the outputs, and they're owned by root in this case
    anyway
  * changed setup-cgroups to just no-op if /sys/fs/cgroup already exists
    so it doesn't mess around with the host
* main entrypoint is scripts/test
  * builds tests using go test -c and runs them with sudo
  * builds latest buildkit from master via the submodule
    * this submodule can be removed in favor of using a released archive
      once a new version is out which supports named oci outputs
* fixed a few bugs that the tests found along the way!
  * manifest.json -> metadata.json (d'oh)
  * XDG_RUNTIME_PATH -> XDG_RUNTIME_DIR (d'oh)
  * build args flag was completely wrong (d'oh)
  * build args file choked on trailing linebreak

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

.gitignore

@@ -0,0 +1,5 @@
+# created by scripts/test
+scripts/.tests
+bin/buildctl
+bin/buildkitd
+bin/buildkit-runc

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "buildkit"]
+	path = buildkit
+	url = https://github.com/moby/buildkit

bin/setup-cgroups

@@ -2,11 +2,13 @@
 
 set -e -u
 
-mkdir -p /sys/fs/cgroup
-mountpoint -q /sys/fs/cgroup || \
-  mount -t tmpfs -o uid=0,gid=0,mode=0755 cgroup /sys/fs/cgroup
+if mountpoint -q /sys/fs/cgroup; then
+  # already mounted; skip
+  exit 0
+fi
 
-mount -o remount,rw none /sys/fs/cgroup
+mkdir -p /sys/fs/cgroup
+mount -t tmpfs -o uid=0,gid=0,mode=0755 cgroup /sys/fs/cgroup
 
 sed -e 1d /proc/cgroups | while read sys hierarchy num enabled; do
   if [ "$enabled" != "1" ]; then

cmd/builder-task/main.go

@@ -30,7 +30,7 @@ func main() {
 	}
 
 	res, err := task.Build(wd, req)
-	failIf("failed to build", err)
+	failIf("build", err)
 
 	responseFile, err := os.Create(req.ResponsePath)
 	failIf("open response path", err)

go.mod

@@ -16,6 +16,7 @@ require (
 	github.com/opencontainers/image-spec v1.0.1
 	github.com/pkg/errors v0.8.1
 	github.com/sirupsen/logrus v1.4.2
+	github.com/stretchr/testify v1.4.0
 	github.com/u-root/u-root v6.0.0+incompatible
 	github.com/vbauerster/mpb v3.4.0+incompatible
 	github.com/vrischmann/envconfig v1.2.0

go.sum

@@ -2,6 +2,7 @@ github.com/VividCortex/ewma v1.1.1 h1:MnEK4VOv6n0RSY4vtRe3h11qjxL3+t0B8yOL8iMXdc
 github.com/VividCortex/ewma v1.1.1/go.mod h1:2Tkkvm3sRDVXaiyucHiACn4cqf7DpdyLvmxzcbUokwA=
 github.com/concourse/go-archive v1.0.1 h1:6jQk0VDiE4G6lNJQ0mLZ7XmxbqI3spO4x0wgVwk4pfo=
 github.com/concourse/go-archive v1.0.1/go.mod h1:Xfo080IPQBmVz3I5ehjCddW3phA2mwv0NFwlpjf5CO8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/fatih/color v1.7.0 h1:DkWD4oS2D8LGGgTQ6IvwJJXSL5Vp2ffcQg58nFV38Ys=
@@ -38,9 +39,13 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/sirupsen/logrus v1.4.2 h1:SPIRibHv4MatM3XXNO2BJeFLZwZ2LvZgfQ5+UNI2im4=
 github.com/sirupsen/logrus v1.4.2/go.mod h1:tLMulIdttU9McNUspp0xgXVQah82FyeX6MwdIuYE2rE=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.1.1 h1:2vfRuCMp5sSVIDSqO8oNnWJq7mPa6KVP3iPIwFBuy8A=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
+github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/u-root/u-root v6.0.0+incompatible h1:YqPGmRoRyYmeg17KIWFRSyVq6LX5T6GSzawyA6wG6EE=
 github.com/u-root/u-root v6.0.0+incompatible/go.mod h1:RYkpo8pTHrNjW08opNd/U6p/RJE7K0D8fXO0d47+3YY=
 github.com/vbauerster/mpb v3.4.0+incompatible h1:mfiiYw87ARaeRW6x5gWwYRUawxaW1tLAD8IceomUCNw=
@@ -72,3 +77,5 @@ gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7 h1:uRGJdciOHaEIrze2W8Q3AKkep
 gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7/go.mod h1:dt/ZhP58zS4L8KSrWDmTeBkI65Dw0HsyUHuEVlX15mw=
 gopkg.in/yaml.v2 v2.2.1 h1:mUhvW9EsL+naU5Q3cakzfE91YhliOondGd6ZrsDBHQE=
 gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

integration_test.go

@@ -0,0 +1,138 @@
+package task_test
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+
+	task "github.com/concourse/builder-task"
+	"github.com/stretchr/testify/suite"
+)
+
+type TaskSuite struct {
+	suite.Suite
+
+	rootDir string
+	req     task.Request
+}
+
+func (s *TaskSuite) SetupSuite() {
+	binDir, err := filepath.Abs("bin")
+	s.NoError(err)
+
+	// inject setup-cgroups and other utilities into the $PATH
+	//
+	// this is also a good place to install buildkitd/buildctl
+	err = os.Setenv("PATH", binDir+":"+os.Getenv("PATH"))
+	s.NoError(err)
+}
+
+func (s *TaskSuite) SetupTest() {
+	var err error
+	s.rootDir, err = ioutil.TempDir("", "builder-task-test")
+	s.NoError(err)
+
+	s.req = task.Request{
+		ResponsePath: filepath.Join(s.rootDir, "response.json"),
+		Config: task.Config{
+			Repository: "builder-task-test",
+		},
+	}
+}
+
+func (s *TaskSuite) TearDownTest() {
+	err := os.RemoveAll(s.rootDir)
+	s.NoError(err)
+}
+
+func (s *TaskSuite) TestMissingRepositoryValidation() {
+	s.req.Config.Repository = ""
+
+	_, err := task.Build(s.rootDir, s.req)
+	s.EqualError(err, "config: repository must be specified")
+}
+
+func (s *TaskSuite) TestBasicBuild() {
+	s.req.Config.ContextPath = "testdata/basic"
+
+	_, err := task.Build(s.rootDir, s.req)
+	s.NoError(err)
+}
+
+func (s *TaskSuite) TestBuildArgs() {
+	s.req.Config.ContextPath = "testdata/build-args"
+	s.req.Config.BuildArgs = []string{
+		"some_arg=some_value",
+		"some_other_arg=some_other_value",
+	}
+
+	// the Dockerfile itself asserts that the arg has been received
+	_, err := task.Build(s.rootDir, s.req)
+	s.NoError(err)
+}
+
+func (s *TaskSuite) TestBuildArgsFile() {
+	s.req.Config.ContextPath = "testdata/build-args"
+	s.req.Config.BuildArgsFile = "testdata/build-args/build_args_file"
+
+	// the Dockerfile itself asserts that the arg has been received
+	_, err := task.Build(s.rootDir, s.req)
+	s.NoError(err)
+}
+
+func (s *TaskSuite) TestBuildArgsStaticAndFile() {
+	s.req.Config.ContextPath = "testdata/build-args"
+	s.req.Config.BuildArgs = []string{"some_arg=some_value"}
+	s.req.Config.BuildArgsFile = "testdata/build-args/build_arg_file"
+
+	// the Dockerfile itself asserts that the arg has been received
+	_, err := task.Build(s.rootDir, s.req)
+	s.NoError(err)
+}
+
+func (s *TaskSuite) TestUnpackRootfs() {
+	s.req.Config.ContextPath = "testdata/unpack-rootfs"
+	s.req.Config.UnpackRootfs = true
+
+	_, err := task.Build(s.rootDir, s.req)
+	s.NoError(err)
+
+	meta, err := s.imageMetadata()
+	s.NoError(err)
+
+	rootfsContent, err := ioutil.ReadFile(s.imagePath("rootfs", "Dockerfile"))
+	s.NoError(err)
+
+	expectedContent, err := ioutil.ReadFile("testdata/unpack-rootfs/Dockerfile")
+	s.NoError(err)
+
+	s.Equal(rootfsContent, expectedContent)
+
+	s.Equal(meta.User, "banana")
+	s.Equal(meta.Env, []string{"PATH=/darkness", "BA=nana"})
+}
+
+func (s *TaskSuite) imagePath(path ...string) string {
+	return filepath.Join(append([]string{s.rootDir, "image"}, path...)...)
+}
+
+func (s *TaskSuite) imageMetadata() (task.ImageMetadata, error) {
+	metadataPayload, err := ioutil.ReadFile(s.imagePath("metadata.json"))
+	if err != nil {
+		return task.ImageMetadata{}, err
+	}
+
+	var meta task.ImageMetadata
+	err = json.Unmarshal(metadataPayload, &meta)
+	if err != nil {
+		return task.ImageMetadata{}, err
+	}
+
+	return meta, nil
+}
+
+func TestSuite(t *testing.T) {
+	suite.Run(t, &TaskSuite{})
+}

scripts/test

@@ -0,0 +1,24 @@
+#!/bin/bash
+
+set -e -u -x
+
+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 -
+fi
+
+go test -c -o scripts/.tests
+sudo scripts/.tests "$@"

task.go

@@ -35,23 +35,23 @@ func Build(rootPath string, req Request) (Response, error) {
 		Outputs: []string{"image", "cache"},
 	}
 
-	err := os.MkdirAll(cacheDir, 0755)
+	err := os.MkdirAll(imageDir, 0755)
 	if err != nil {
 		return Response{}, errors.Wrap(err, "create image output folder")
 	}
 
-	cfg := req.Config
-	err = sanitize(&cfg)
+	err = os.MkdirAll(cacheDir, 0755)
 	if err != nil {
-		return Response{}, errors.Wrap(err, "config")
+		return Response{}, errors.Wrap(err, "create cache output folder")
 	}
 
-	err = run(os.Stdout, "setup-cgroups")
+	cfg := req.Config
+	err = sanitize(&cfg)
 	if err != nil {
-		return Response{}, errors.Wrap(err, "setup cgroups")
+		return Response{}, errors.Wrap(err, "config")
 	}
 
-	addr, err := spawnBuildkitd("/var/log/buildkitd.log")
+	addr, err := spawnBuildkitd()
 	if err != nil {
 		return Response{}, errors.Wrap(err, "spawn buildkitd")
 	}
@@ -64,8 +64,8 @@ func Build(rootPath string, req Request) (Response, error) {
 		"--frontend", "dockerfile.v0",
 		"--local", "context=" + cfg.ContextPath,
 		"--local", "dockerfile=" + dockerfileDir,
-		"--frontend-opt", "filename=" + dockerfileName,
-		"--export-cache", "type=local,mode=min,dest=cache",
+		"--opt", "filename=" + dockerfileName,
+		"--export-cache", "type=local,mode=min,dest=" + cacheDir,
 	}
 
 	if _, err := os.Stat(filepath.Join(cacheDir, "index.json")); err == nil {
@@ -90,7 +90,7 @@ func Build(rootPath string, req Request) (Response, error) {
 
 	for _, arg := range cfg.BuildArgs {
 		buildctlArgs = append(buildctlArgs,
-			"--build-arg", arg,
+			"--opt", "build-arg:"+arg,
 		)
 	}
 
@@ -116,7 +116,7 @@ func Build(rootPath string, req Request) (Response, error) {
 func unpackRootfs(dest string, ociImagePath string, cfg Config) error {
 	layoutDir := filepath.Join(dest, "layout")
 	rootfsDir := filepath.Join(dest, "rootfs")
-	manifestPath := filepath.Join(dest, "manifest.json")
+	metadataPath := filepath.Join(dest, "metadata.json")
 
 	logrus.Debug("unpacking oci layout")
 
@@ -175,12 +175,12 @@ func unpackRootfs(dest string, ociImagePath string, cfg Config) error {
 			return errors.Wrap(err, "get image from oci layout")
 		}
 
-		err = unpackImage(rootfsDir, image, false)
+		err = unpackImage(rootfsDir, image, cfg.Debug)
 		if err != nil {
 			return errors.Wrap(err, "unpack image")
 		}
 
-		err = writeImageManifest(manifestPath, image)
+		err = writeImageManifest(metadataPath, image)
 		if err != nil {
 			return errors.Wrap(err, "write image manifest")
 		}
@@ -195,13 +195,13 @@ func unpackRootfs(dest string, ociImagePath string, cfg Config) error {
 	return nil
 }
 
-func writeImageManifest(manifestPath string, image v1.Image) error {
+func writeImageManifest(metadataPath string, image v1.Image) error {
 	cfg, err := image.ConfigFile()
 	if err != nil {
 		return errors.Wrap(err, "load image config")
 	}
 
-	meta, err := os.Create(manifestPath)
+	meta, err := os.Create(metadataPath)
 	if err != nil {
 		return errors.Wrap(err, "create metadata file")
 	}
@@ -272,6 +272,11 @@ func sanitize(cfg *Config) error {
 		}
 
 		for _, arg := range strings.Split(string(buildArgs), "\n") {
+			if len(arg) == 0 {
+				// skip blank lines
+				continue
+			}
+
 			cfg.BuildArgs = append(cfg.BuildArgs, arg)
 		}
 	}
@@ -291,15 +296,25 @@ func run(out io.Writer, path string, args ...string) error {
 	return cmd.Run()
 }
 
-func spawnBuildkitd(logPath string) (string, error) {
-	runPath := os.Getenv("XDG_RUNTIME_PATH")
-	if runPath == "" {
-		runPath = "/run"
+func spawnBuildkitd() (string, error) {
+	err := run(os.Stdout, "setup-cgroups")
+	if err != nil {
+		return "", errors.Wrap(err, "setup cgroups")
+	}
+
+	var logPath string
+
+	runDir := os.Getenv("XDG_RUNTIME_DIR")
+	if runDir == "" {
+		runDir = "/run"
+		logPath = "/var/log/buildkitd.log"
+	} else {
+		logPath = filepath.Join(runDir, "buildkitd.log")
 	}
 
 	addr := (&url.URL{
 		Scheme: "unix",
-		Path:   path.Join(runPath, "buildkitd", "buildkitd.sock"),
+		Path:   path.Join(runDir, "buildkitd", "buildkitd.sock"),
 	}).String()
 
 	buildkitdFlags := []string{"--addr=" + addr}

testdata/basic/Dockerfile

@@ -0,0 +1 @@
+FROM scratch

testdata/build-args/Dockerfile

@@ -0,0 +1,5 @@
+FROM busybox
+ARG some_arg
+ARG some_other_arg
+RUN test "$some_arg" = "some_value"
+RUN test "$some_other_arg" = "some_other_value"

testdata/build-args/build_arg_file

@@ -0,0 +1 @@
+some_other_arg=some_other_value

testdata/build-args/build_args_file

@@ -0,0 +1,2 @@
+some_arg=some_value
+some_other_arg=some_other_value

testdata/unpack-rootfs/Dockerfile

@@ -0,0 +1,5 @@
+FROM scratch
+USER banana
+ADD Dockerfile /Dockerfile
+ENV PATH=/darkness
+ENV BA=nana