Refactor API build endpoint to be more compliant

* Refactor/Rename channel.WriteCloser() to encapsulate the channel
* Refactor build endpoint to "live" stream buildah output channels
  over API rather then buffering output
* Refactor bindings/tunnel build because endpoint changes
  * building tar file now in bindings rather then depending on
    caller
* Cleanup initiating extra image engine
* Remove setting fields to zero values (less noise in code)
* Update tests to support remote builds

Fixes #7136
Fixes #7137

Signed-off-by: Jhon Honce <jhonce@redhat.com>

10 files changed, 454 insertions, 350 deletions

diff --git a/pkg/api/handlers/compat/images_build.go b/pkg/api/handlers/compat/images_build.go
index 9601f5e18..fbaf8d10a 100644
--- a/pkg/api/handlers/compat/images_build.go
+++ b/pkg/api/handlers/compat/images_build.go
@@ -1,7 +1,7 @@
 package compat
 
 import (
-	"bytes"
+	"context"
 	"encoding/base64"
 	"encoding/json"
 	"fmt"
@@ -18,8 +18,10 @@ import (
 	"github.com/containers/podman/v2/libpod"
 	"github.com/containers/podman/v2/pkg/api/handlers"
 	"github.com/containers/podman/v2/pkg/api/handlers/utils"
+	"github.com/containers/podman/v2/pkg/channel"
 	"github.com/containers/storage/pkg/archive"
 	"github.com/gorilla/schema"
+	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
 
@@ -47,12 +49,25 @@ func BuildImage(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	anchorDir, err := extractTarFile(r)
+	contextDirectory, err := extractTarFile(r)
 	if err != nil {
 		utils.InternalServerError(w, err)
 		return
 	}
-	defer os.RemoveAll(anchorDir)
+
+	defer func() {
+		if logrus.IsLevelEnabled(logrus.DebugLevel) {
+			if v, found := os.LookupEnv("PODMAN_RETAIN_BUILD_ARTIFACT"); found {
+				if keep, _ := strconv.ParseBool(v); keep {
+					return
+				}
+			}
+		}
+		err := os.RemoveAll(filepath.Dir(contextDirectory))
+		if err != nil {
+			logrus.Warn(errors.Wrapf(err, "failed to remove build scratch directory %q", filepath.Dir(contextDirectory)))
+		}
+	}()
 
 	query := struct {
 		Dockerfile  string   `schema:"dockerfile"`
@@ -67,10 +82,10 @@ func BuildImage(w http.ResponseWriter, r *http.Request) {
 		ForceRm     bool     `schema:"forcerm"`
 		Memory      int64    `schema:"memory"`
 		MemSwap     int64    `schema:"memswap"`
-		CpuShares   uint64   `schema:"cpushares"`  //nolint
-		CpuSetCpus  string   `schema:"cpusetcpus"` //nolint
-		CpuPeriod   uint64   `schema:"cpuperiod"`  //nolint
-		CpuQuota    int64    `schema:"cpuquota"`   //nolint
+		CpuShares   uint64   `schema:"cpushares"`  // nolint
+		CpuSetCpus  string   `schema:"cpusetcpus"` // nolint
+		CpuPeriod   uint64   `schema:"cpuperiod"`  // nolint
+		CpuQuota    int64    `schema:"cpuquota"`   // nolint
 		BuildArgs   string   `schema:"buildargs"`
 		ShmSize     int      `schema:"shmsize"`
 		Squash      bool     `schema:"squash"`
@@ -81,52 +96,32 @@ func BuildImage(w http.ResponseWriter, r *http.Request) {
 		Outputs     string   `schema:"outputs"`
 		Registry    string   `schema:"registry"`
 	}{
-		Dockerfile:  "Dockerfile",
-		Tag:         []string{},
-		ExtraHosts:  "",
-		Remote:      "",
-		Quiet:       false,
-		NoCache:     false,
-		CacheFrom:   "",
-		Pull:        false,
-		Rm:          true,
-		ForceRm:     false,
-		Memory:      0,
-		MemSwap:     0,
-		CpuShares:   0,
-		CpuSetCpus:  "",
-		CpuPeriod:   0,
-		CpuQuota:    0,
-		BuildArgs:   "",
-		ShmSize:     64 * 1024 * 1024,
-		Squash:      false,
-		Labels:      "",
-		NetworkMode: "",
-		Platform:    "",
-		Target:      "",
-		Outputs:     "",
-		Registry:    "docker.io",
+		Dockerfile: "Dockerfile",
+		Tag:        []string{},
+		Rm:         true,
+		ShmSize:    64 * 1024 * 1024,
+		Registry:   "docker.io",
 	}
+
 	decoder := r.Context().Value("decoder").(*schema.Decoder)
 	if err := decoder.Decode(&query, r.URL.Query()); err != nil {
 		utils.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest, err)
 		return
 	}
 
-	var (
-		output          string
-		additionalNames []string
-	)
+	var output string
 	if len(query.Tag) > 0 {
 		output = query.Tag[0]
 	}
+	if _, found := r.URL.Query()["target"]; found {
+		output = query.Target
+	}
+
+	var additionalNames []string
 	if len(query.Tag) > 1 {
 		additionalNames = query.Tag[1:]
 	}
 
-	if _, found := r.URL.Query()["target"]; found {
-		output = query.Target
-	}
 	var buildArgs = map[string]string{}
 	if _, found := r.URL.Query()["buildargs"]; found {
 		if err := json.Unmarshal([]byte(query.BuildArgs), &buildArgs); err != nil {
@@ -156,95 +151,136 @@ func BuildImage(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	// build events will be recorded here
-	var (
-		buildEvents = []string{}
-		progress    = bytes.Buffer{}
-	)
+	// Channels all mux'ed in select{} below to follow API build protocol
+	stdout := channel.NewWriter(make(chan []byte, 1))
+	defer stdout.Close()
+
+	auxout := channel.NewWriter(make(chan []byte, 1))
+	defer auxout.Close()
+
+	stderr := channel.NewWriter(make(chan []byte, 1))
+	defer stderr.Close()
+
+	reporter := channel.NewWriter(make(chan []byte, 1))
+	defer reporter.Close()
 
 	buildOptions := imagebuildah.BuildOptions{
-		ContextDirectory:               filepath.Join(anchorDir, "build"),
+		ContextDirectory:               contextDirectory,
 		PullPolicy:                     pullPolicy,
 		Registry:                       query.Registry,
 		IgnoreUnrecognizedInstructions: true,
 		Quiet:                          query.Quiet,
 		Isolation:                      buildah.IsolationChroot,
-		Runtime:                        "",
-		RuntimeArgs:                    nil,
-		TransientMounts:                nil,
 		Compression:                    archive.Gzip,
 		Args:                           buildArgs,
 		Output:                         output,
 		AdditionalTags:                 additionalNames,
-		Log: func(format string, args ...interface{}) {
-			buildEvents = append(buildEvents, fmt.Sprintf(format, args...))
-		},
-		In:                  nil,
-		Out:                 &progress,
-		Err:                 &progress,
-		SignaturePolicyPath: "",
-		ReportWriter:        &progress,
-		OutputFormat:        buildah.Dockerv2ImageManifest,
-		SystemContext:       nil,
-		NamespaceOptions:    nil,
-		ConfigureNetwork:    0,
-		CNIPluginPath:       "",
-		CNIConfigDir:        "",
-		IDMappingOptions:    nil,
-		AddCapabilities:     nil,
-		DropCapabilities:    nil,
+		Out:                            stdout,
+		Err:                            auxout,
+		ReportWriter:                   reporter,
+		OutputFormat:                   buildah.Dockerv2ImageManifest,
 		CommonBuildOpts: &buildah.CommonBuildOptions{
-			AddHost:            nil,
-			CgroupParent:       "",
-			CPUPeriod:          query.CpuPeriod,
-			CPUQuota:           query.CpuQuota,
-			CPUShares:          query.CpuShares,
-			CPUSetCPUs:         query.CpuSetCpus,
-			CPUSetMems:         "",
-			HTTPProxy:          false,
-			Memory:             query.Memory,
-			DNSSearch:          nil,
-			DNSServers:         nil,
-			DNSOptions:         nil,
-			MemorySwap:         query.MemSwap,
-			LabelOpts:          nil,
-			SeccompProfilePath: "",
-			ApparmorProfile:    "",
-			ShmSize:            strconv.Itoa(query.ShmSize),
-			Ulimit:             nil,
-			Volumes:            nil,
+			CPUPeriod:  query.CpuPeriod,
+			CPUQuota:   query.CpuQuota,
+			CPUShares:  query.CpuShares,
+			CPUSetCPUs: query.CpuSetCpus,
+			Memory:     query.Memory,
+			MemorySwap: query.MemSwap,
+			ShmSize:    strconv.Itoa(query.ShmSize),
 		},
-		DefaultMountsFilePath:   "",
-		IIDFile:                 "",
 		Squash:                  query.Squash,
 		Labels:                  labels,
-		Annotations:             nil,
-		OnBuild:                 nil,
-		Layers:                  false,
 		NoCache:                 query.NoCache,
 		RemoveIntermediateCtrs:  query.Rm,
 		ForceRmIntermediateCtrs: query.ForceRm,
-		BlobDirectory:           "",
 		Target:                  query.Target,
-		Devices:                 nil,
 	}
 
 	runtime := r.Context().Value("runtime").(*libpod.Runtime)
-	id, _, err := runtime.Build(r.Context(), buildOptions, query.Dockerfile)
-	if err != nil {
-		utils.InternalServerError(w, err)
-		return
+	runCtx, cancel := context.WithCancel(context.Background())
+	var imageID string
+	go func() {
+		defer cancel()
+		imageID, _, err = runtime.Build(r.Context(), buildOptions, query.Dockerfile)
+		if err != nil {
+			stderr.Write([]byte(err.Error() + "\n"))
+		}
+	}()
+
+	flush := func() {
+		if flusher, ok := w.(http.Flusher); ok {
+			flusher.Flush()
+		}
 	}
 
-	// Find image ID that was built...
-	utils.WriteResponse(w, http.StatusOK,
-		struct {
-			Stream string `json:"stream"`
-		}{
-			Stream: progress.String() + "\n" +
-				strings.Join(buildEvents, "\n") +
-				fmt.Sprintf("\nSuccessfully built %s\n", id),
-		})
+	// Send headers and prime client for stream to come
+	w.WriteHeader(http.StatusOK)
+	w.Header().Add("Content-Type", "application/json")
+	flush()
+
+	var failed bool
+
+	body := w.(io.Writer)
+	if logrus.IsLevelEnabled(logrus.DebugLevel) {
+		if v, found := os.LookupEnv("PODMAN_RETAIN_BUILD_ARTIFACT"); found {
+			if keep, _ := strconv.ParseBool(v); keep {
+				t, _ := ioutil.TempFile("", "build_*_server")
+				defer t.Close()
+				body = io.MultiWriter(t, w)
+			}
+		}
+	}
+
+	enc := json.NewEncoder(body)
+	enc.SetEscapeHTML(true)
+loop:
+	for {
+		m := struct {
+			Stream string `json:"stream,omitempty"`
+			Error  string `json:"error,omitempty"`
+		}{}
+
+		select {
+		case e := <-stdout.Chan():
+			m.Stream = string(e)
+			if err := enc.Encode(m); err != nil {
+				stderr.Write([]byte(err.Error()))
+			}
+			flush()
+		case e := <-auxout.Chan():
+			m.Stream = string(e)
+			if err := enc.Encode(m); err != nil {
+				stderr.Write([]byte(err.Error()))
+			}
+			flush()
+		case e := <-reporter.Chan():
+			m.Stream = string(e)
+			if err := enc.Encode(m); err != nil {
+				stderr.Write([]byte(err.Error()))
+			}
+			flush()
+		case e := <-stderr.Chan():
+			failed = true
+			m.Error = string(e)
+			if err := enc.Encode(m); err != nil {
+				logrus.Warnf("Failed to json encode error %q", err.Error())
+			}
+			flush()
+		case <-runCtx.Done():
+			if !failed {
+				if utils.IsLibpodRequest(r) {
+					m.Stream = imageID
+				} else {
+					m.Stream = fmt.Sprintf("Successfully built %12.12s\n", imageID)
+				}
+				if err := enc.Encode(m); err != nil {
+					logrus.Warnf("Failed to json encode error %q", err.Error())
+				}
+				flush()
+			}
+			break loop
+		}
+	}
 }
 
 func extractTarFile(r *http.Request) (string, error) {
@@ -253,10 +289,9 @@ func extractTarFile(r *http.Request) (string, error) {
 	if err != nil {
 		return "", err
 	}
-	buildDir := filepath.Join(anchorDir, "build")
 
 	path := filepath.Join(anchorDir, "tarBall")
-	tarBall, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0666)
+	tarBall, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0600)
 	if err != nil {
 		return "", err
 	}
@@ -265,14 +300,17 @@ func extractTarFile(r *http.Request) (string, error) {
 	// Content-Length not used as too many existing API clients didn't honor it
 	_, err = io.Copy(tarBall, r.Body)
 	r.Body.Close()
-
 	if err != nil {
 		return "", fmt.Errorf("failed Request: Unable to copy tar file from request body %s", r.RequestURI)
 	}
 
-	_, _ = tarBall.Seek(0, 0)
-	if err := archive.Untar(tarBall, buildDir, &archive.TarOptions{}); err != nil {
+	buildDir := filepath.Join(anchorDir, "build")
+	err = os.Mkdir(buildDir, 0700)
+	if err != nil {
 		return "", err
 	}
-	return anchorDir, nil
+
+	_, _ = tarBall.Seek(0, 0)
+	err = archive.Untar(tarBall, buildDir, nil)
+	return buildDir, err
 }
diff --git a/pkg/bindings/images/build.go b/pkg/bindings/images/build.go
new file mode 100644
index 000000000..9082670a7
--- /dev/null
+++ b/pkg/bindings/images/build.go
@@ -0,0 +1,227 @@
+package images
+
+import (
+	"archive/tar"
+	"context"
+	"encoding/json"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"strings"
+
+	"github.com/containers/buildah"
+	"github.com/containers/podman/v2/pkg/bindings"
+	"github.com/containers/podman/v2/pkg/domain/entities"
+	"github.com/docker/go-units"
+	"github.com/hashicorp/go-multierror"
+	jsoniter "github.com/json-iterator/go"
+	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
+)
+
+// Build creates an image using a containerfile reference
+func Build(ctx context.Context, containerFiles []string, options entities.BuildOptions) (*entities.BuildReport, error) {
+	params := url.Values{}
+
+	if t := options.Output; len(t) > 0 {
+		params.Set("t", t)
+	}
+	for _, tag := range options.AdditionalTags {
+		params.Add("t", tag)
+	}
+	if options.Quiet {
+		params.Set("q", "1")
+	}
+	if options.NoCache {
+		params.Set("nocache", "1")
+	}
+	//	 TODO cachefrom
+	if options.PullPolicy == buildah.PullAlways {
+		params.Set("pull", "1")
+	}
+	if options.RemoveIntermediateCtrs {
+		params.Set("rm", "1")
+	}
+	if options.ForceRmIntermediateCtrs {
+		params.Set("forcerm", "1")
+	}
+	if mem := options.CommonBuildOpts.Memory; mem > 0 {
+		params.Set("memory", strconv.Itoa(int(mem)))
+	}
+	if memSwap := options.CommonBuildOpts.MemorySwap; memSwap > 0 {
+		params.Set("memswap", strconv.Itoa(int(memSwap)))
+	}
+	if cpuShares := options.CommonBuildOpts.CPUShares; cpuShares > 0 {
+		params.Set("cpushares", strconv.Itoa(int(cpuShares)))
+	}
+	if cpuSetCpus := options.CommonBuildOpts.CPUSetCPUs; len(cpuSetCpus) > 0 {
+		params.Set("cpusetcpues", cpuSetCpus)
+	}
+	if cpuPeriod := options.CommonBuildOpts.CPUPeriod; cpuPeriod > 0 {
+		params.Set("cpuperiod", strconv.Itoa(int(cpuPeriod)))
+	}
+	if cpuQuota := options.CommonBuildOpts.CPUQuota; cpuQuota > 0 {
+		params.Set("cpuquota", strconv.Itoa(int(cpuQuota)))
+	}
+	if buildArgs := options.Args; len(buildArgs) > 0 {
+		bArgs, err := jsoniter.MarshalToString(buildArgs)
+		if err != nil {
+			return nil, err
+		}
+		params.Set("buildargs", bArgs)
+	}
+	if shmSize := options.CommonBuildOpts.ShmSize; len(shmSize) > 0 {
+		shmBytes, err := units.RAMInBytes(shmSize)
+		if err != nil {
+			return nil, err
+		}
+		params.Set("shmsize", strconv.Itoa(int(shmBytes)))
+	}
+	if options.Squash {
+		params.Set("squash", "1")
+	}
+	if labels := options.Labels; len(labels) > 0 {
+		l, err := jsoniter.MarshalToString(labels)
+		if err != nil {
+			return nil, err
+		}
+		params.Set("labels", l)
+	}
+
+	stdout := io.Writer(os.Stdout)
+	if options.Out != nil {
+		stdout = options.Out
+	}
+
+	// TODO network?
+
+	var platform string
+	if OS := options.OS; len(OS) > 0 {
+		platform += OS
+	}
+	if arch := options.Architecture; len(arch) > 0 {
+		platform += "/" + arch
+	}
+	if len(platform) > 0 {
+		params.Set("platform", platform)
+	}
+
+	entries := make([]string, len(containerFiles))
+	copy(entries, containerFiles)
+	entries = append(entries, options.ContextDirectory)
+	tarfile, err := nTar(entries...)
+	if err != nil {
+		return nil, err
+	}
+	defer tarfile.Close()
+	params.Set("dockerfile", filepath.Base(containerFiles[0]))
+
+	conn, err := bindings.GetClient(ctx)
+	if err != nil {
+		return nil, err
+	}
+	response, err := conn.DoRequest(tarfile, http.MethodPost, "/build", params, nil)
+	if err != nil {
+		return nil, err
+	}
+	defer response.Body.Close()
+
+	if !response.IsSuccess() {
+		return nil, response.Process(err)
+	}
+
+	body := response.Body.(io.Reader)
+	if logrus.IsLevelEnabled(logrus.DebugLevel) {
+		if v, found := os.LookupEnv("PODMAN_RETAIN_BUILD_ARTIFACT"); found {
+			if keep, _ := strconv.ParseBool(v); keep {
+				t, _ := ioutil.TempFile("", "build_*_client")
+				defer t.Close()
+				body = io.TeeReader(response.Body, t)
+			}
+		}
+	}
+
+	dec := json.NewDecoder(body)
+	re := regexp.MustCompile(`[0-9a-f]{12}`)
+
+	var id string
+	for {
+		var s struct {
+			Stream string `json:"stream,omitempty"`
+			Error  string `json:"error,omitempty"`
+		}
+		if err := dec.Decode(&s); err != nil {
+			if errors.Is(err, io.EOF) {
+				return &entities.BuildReport{ID: id}, nil
+			}
+			s.Error = err.Error() + "\n"
+		}
+
+		switch {
+		case s.Stream != "":
+			stdout.Write([]byte(s.Stream))
+			if re.Match([]byte(s.Stream)) {
+				id = s.Stream
+			}
+		case s.Error != "":
+			return nil, errors.New(s.Error)
+		default:
+			return &entities.BuildReport{ID: id}, errors.New("failed to parse build results stream, unexpected input")
+		}
+	}
+}
+
+func nTar(sources ...string) (io.ReadCloser, error) {
+	if len(sources) == 0 {
+		return nil, errors.New("No source(s) provided for build")
+	}
+
+	pr, pw := io.Pipe()
+	tw := tar.NewWriter(pw)
+
+	var merr error
+	go func() {
+		defer pw.Close()
+		defer tw.Close()
+
+		for _, src := range sources {
+			s := src
+			err := filepath.Walk(s, func(path string, info os.FileInfo, err error) error {
+				if err != nil {
+					return err
+				}
+				if !info.Mode().IsRegular() || path == s {
+					return nil
+				}
+
+				f, lerr := os.Open(path)
+				if lerr != nil {
+					return lerr
+				}
+
+				name := strings.TrimPrefix(path, s+string(filepath.Separator))
+				hdr, lerr := tar.FileInfoHeader(info, name)
+				if lerr != nil {
+					f.Close()
+					return lerr
+				}
+				hdr.Name = name
+				if lerr := tw.WriteHeader(hdr); lerr != nil {
+					f.Close()
+					return lerr
+				}
+
+				_, cerr := io.Copy(tw, f)
+				f.Close()
+				return cerr
+			})
+			merr = multierror.Append(merr, err)
+		}
+	}()
+	return pr, merr
+}
diff --git a/pkg/bindings/images/images.go b/pkg/bindings/images/images.go
index a80c94025..05ab25d5b 100644
--- a/pkg/bindings/images/images.go
+++ b/pkg/bindings/images/images.go
@@ -1,7 +1,6 @@
 package images
 
 import (
-	"bytes"
 	"context"
 	"fmt"
 	"io"
@@ -9,14 +8,11 @@ import (
 	"net/url"
 	"strconv"
 
-	"github.com/containers/buildah"
 	"github.com/containers/image/v5/types"
 	"github.com/containers/podman/v2/pkg/api/handlers"
 	"github.com/containers/podman/v2/pkg/auth"
 	"github.com/containers/podman/v2/pkg/bindings"
 	"github.com/containers/podman/v2/pkg/domain/entities"
-	"github.com/docker/go-units"
-	jsoniter "github.com/json-iterator/go"
 	"github.com/pkg/errors"
 )
 
@@ -242,112 +238,6 @@ func Untag(ctx context.Context, nameOrID, tag, repo string) error {
 	return response.Process(nil)
 }
 
-// Build creates an image using a containerfile reference
-func Build(ctx context.Context, containerFiles []string, options entities.BuildOptions, tarfile io.Reader) (*entities.BuildReport, error) {
-	var (
-		platform string
-		report   entities.BuildReport
-	)
-	conn, err := bindings.GetClient(ctx)
-	if err != nil {
-		return nil, err
-	}
-	params := url.Values{}
-	params.Set("dockerfile", containerFiles[0])
-	if t := options.Output; len(t) > 0 {
-		params.Set("t", t)
-	}
-	for _, tag := range options.AdditionalTags {
-		params.Add("t", tag)
-	}
-	//	TODO Remote, Quiet
-	if options.NoCache {
-		params.Set("nocache", "1")
-	}
-	//	 TODO cachefrom
-	if options.PullPolicy == buildah.PullAlways {
-		params.Set("pull", "1")
-	}
-	if options.RemoveIntermediateCtrs {
-		params.Set("rm", "1")
-	}
-	if options.ForceRmIntermediateCtrs {
-		params.Set("forcerm", "1")
-	}
-	if mem := options.CommonBuildOpts.Memory; mem > 0 {
-		params.Set("memory", strconv.Itoa(int(mem)))
-	}
-	if memSwap := options.CommonBuildOpts.MemorySwap; memSwap > 0 {
-		params.Set("memswap", strconv.Itoa(int(memSwap)))
-	}
-	if cpuShares := options.CommonBuildOpts.CPUShares; cpuShares > 0 {
-		params.Set("cpushares", strconv.Itoa(int(cpuShares)))
-	}
-	if cpuSetCpus := options.CommonBuildOpts.CPUSetCPUs; len(cpuSetCpus) > 0 {
-		params.Set("cpusetcpues", cpuSetCpus)
-	}
-	if cpuPeriod := options.CommonBuildOpts.CPUPeriod; cpuPeriod > 0 {
-		params.Set("cpuperiod", strconv.Itoa(int(cpuPeriod)))
-	}
-	if cpuQuota := options.CommonBuildOpts.CPUQuota; cpuQuota > 0 {
-		params.Set("cpuquota", strconv.Itoa(int(cpuQuota)))
-	}
-	if buildArgs := options.Args; len(buildArgs) > 0 {
-		bArgs, err := jsoniter.MarshalToString(buildArgs)
-		if err != nil {
-			return nil, err
-		}
-		params.Set("buildargs", bArgs)
-	}
-	if shmSize := options.CommonBuildOpts.ShmSize; len(shmSize) > 0 {
-		shmBytes, err := units.RAMInBytes(shmSize)
-		if err != nil {
-			return nil, err
-		}
-		params.Set("shmsize", strconv.Itoa(int(shmBytes)))
-	}
-	if options.Squash {
-		params.Set("squash", "1")
-	}
-	if labels := options.Labels; len(labels) > 0 {
-		l, err := jsoniter.MarshalToString(labels)
-		if err != nil {
-			return nil, err
-		}
-		params.Set("labels", l)
-	}
-
-	// TODO network?
-	if OS := options.OS; len(OS) > 0 {
-		platform += OS
-	}
-	if arch := options.Architecture; len(arch) > 0 {
-		platform += "/" + arch
-	}
-	if len(platform) > 0 {
-		params.Set("platform", platform)
-	}
-	//	TODO outputs?
-
-	response, err := conn.DoRequest(tarfile, http.MethodPost, "/build", params, nil)
-	if err != nil {
-		return nil, err
-	}
-	var streamReponse []byte
-	bb := bytes.NewBuffer(streamReponse)
-	if _, err = io.Copy(bb, response.Body); err != nil {
-		return nil, err
-	}
-	var s struct {
-		Stream string `json:"stream"`
-	}
-	if err := jsoniter.UnmarshalFromString(bb.String(), &s); err != nil {
-		return nil, err
-	}
-	fmt.Print(s.Stream)
-	return &report, nil
-}
-
 // Imports adds the given image to the local image store.  This can be done by file and the given reader
 // or via the url parameter.  Additional metadata can be associated with the image by using the changes and
 // message parameters.  The image can also be tagged given a reference. One of url OR r must be provided.
diff --git a/pkg/channel/doc.go b/pkg/channel/doc.go
new file mode 100644
index 000000000..656fbddaa
--- /dev/null
+++ b/pkg/channel/doc.go
@@ -0,0 +1,17 @@
+/*
+Package channel provides helper structs/methods/funcs for working with channels
+
+Proxy from an io.Writer to a channel:
+
+	w := channel.NewWriter(make(chan []byte, 10))
+	go func() {
+		w.Write([]byte("Hello, World"))
+	}()
+
+	fmt.Println(string(<-w.Chan()))
+    w.Close()
+
+Use of the constructor is required to initialize the channel.
+Provide a channel of sufficient size to handle messages from writer(s).
+*/
+package channel
diff --git a/pkg/channel/writer.go b/pkg/channel/writer.go
new file mode 100644
index 000000000..dbb38e416
--- /dev/null
+++ b/pkg/channel/writer.go
@@ -0,0 +1,53 @@
+package channel
+
+import (
+	"io"
+	"sync"
+
+	"github.com/pkg/errors"
+)
+
+// WriteCloser is an io.WriteCloser that that proxies Write() calls to a channel
+// The []byte buffer of the Write() is queued on the channel as one message.
+type WriteCloser interface {
+	io.WriteCloser
+	Chan() <-chan []byte
+}
+
+type writeCloser struct {
+	ch  chan []byte
+	mux sync.Mutex
+}
+
+// NewWriter initializes a new channel writer
+func NewWriter(c chan []byte) WriteCloser {
+	return &writeCloser{
+		ch: c,
+	}
+}
+
+// Chan returns the R/O channel behind WriteCloser
+func (w *writeCloser) Chan() <-chan []byte {
+	return w.ch
+}
+
+// Write method for WriteCloser
+func (w *writeCloser) Write(b []byte) (int, error) {
+	if w == nil || w.ch == nil {
+		return 0, errors.New("use channel.NewWriter() to initialize a WriteCloser")
+	}
+
+	w.mux.Lock()
+	buf := make([]byte, len(b))
+	copy(buf, b)
+	w.ch <- buf
+	w.mux.Unlock()
+
+	return len(b), nil
+}
+
+// Close method for WriteCloser
+func (w *writeCloser) Close() error {
+	close(w.ch)
+	return nil
+}
diff --git a/pkg/channelwriter/channelwriter.go b/pkg/channelwriter/channelwriter.go
deleted file mode 100644
index d51400eb3..000000000
--- a/pkg/channelwriter/channelwriter.go
+++ /dev/null
@@ -1,34 +0,0 @@
-package channelwriter
-
-import "github.com/pkg/errors"
-
-// Writer is an io.writer-like object that "writes" to a channel
-// instead of a buffer or file, etc. It is handy for varlink endpoints when
-// needing to handle endpoints that do logging "real-time"
-type Writer struct {
-	ByteChannel chan []byte
-}
-
-// NewChannelWriter creates a new channel writer and adds a
-// byte slice channel into it.
-func NewChannelWriter() *Writer {
-	byteChannel := make(chan []byte)
-	return &Writer{
-		ByteChannel: byteChannel,
-	}
-}
-
-// Write method for Writer
-func (c *Writer) Write(w []byte) (int, error) {
-	if c.ByteChannel == nil {
-		return 0, errors.New("channel writer channel cannot be nil")
-	}
-	c.ByteChannel <- w
-	return len(w), nil
-}
-
-// Close method for Writer
-func (c *Writer) Close() error {
-	close(c.ByteChannel)
-	return nil
-}
diff --git a/pkg/domain/infra/abi/images.go b/pkg/domain/infra/abi/images.go
index 23aef9573..cc3ec37fb 100644
--- a/pkg/domain/infra/abi/images.go
+++ b/pkg/domain/infra/abi/images.go
@@ -535,6 +535,7 @@ func (ir *ImageEngine) Config(_ context.Context) (*config.Config, error) {
 }
 
 func (ir *ImageEngine) Build(ctx context.Context, containerFiles []string, opts entities.BuildOptions) (*entities.BuildReport, error) {
+
 	id, _, err := ir.Libpod.Build(ctx, opts.BuildOptions, containerFiles...)
 	if err != nil {
 		return nil, err
diff --git a/pkg/domain/infra/tunnel/images.go b/pkg/domain/infra/tunnel/images.go
index 185cc2f9a..50b8342a3 100644
--- a/pkg/domain/infra/tunnel/images.go
+++ b/pkg/domain/infra/tunnel/images.go
@@ -1,13 +1,9 @@
 package tunnel
 
 import (
-	"archive/tar"
-	"bytes"
 	"context"
-	"io"
 	"io/ioutil"
 	"os"
-	"path/filepath"
 	"strings"
 	"time"
 
@@ -18,9 +14,7 @@ import (
 	"github.com/containers/podman/v2/pkg/domain/entities"
 	"github.com/containers/podman/v2/pkg/domain/utils"
 	utils2 "github.com/containers/podman/v2/utils"
-	"github.com/containers/storage/pkg/archive"
 	"github.com/pkg/errors"
-	"github.com/sirupsen/logrus"
 )
 
 func (ir *ImageEngine) Exists(_ context.Context, nameOrID string) (*entities.BoolReport, error) {
@@ -311,28 +305,8 @@ func (ir *ImageEngine) Config(_ context.Context) (*config.Config, error) {
 	return config.Default()
 }
 
-func (ir *ImageEngine) Build(ctx context.Context, containerFiles []string, opts entities.BuildOptions) (*entities.BuildReport, error) {
-	var tarReader io.Reader
-	tarfile, err := archive.Tar(opts.ContextDirectory, 0)
-	if err != nil {
-		return nil, err
-	}
-	tarReader = tarfile
-	cwd, err := os.Getwd()
-	if err != nil {
-		return nil, err
-	}
-	if cwd != opts.ContextDirectory {
-		fn := func(h *tar.Header, r io.Reader) (data []byte, update bool, skip bool, err error) {
-			h.Name = filepath.Join(filepath.Base(opts.ContextDirectory), h.Name)
-			return nil, false, false, nil
-		}
-		tarReader, err = transformArchive(tarfile, false, fn)
-		if err != nil {
-			return nil, err
-		}
-	}
-	return images.Build(ir.ClientCxt, containerFiles, opts, tarReader)
+func (ir *ImageEngine) Build(_ context.Context, containerFiles []string, opts entities.BuildOptions) (*entities.BuildReport, error) {
+	return images.Build(ir.ClientCxt, containerFiles, opts)
 }
 
 func (ir *ImageEngine) Tree(ctx context.Context, nameOrID string, opts entities.ImageTreeOptions) (*entities.ImageTreeReport, error) {
@@ -346,65 +320,3 @@ func (ir *ImageEngine) Shutdown(_ context.Context) {
 func (ir *ImageEngine) Sign(ctx context.Context, names []string, options entities.SignOptions) (*entities.SignReport, error) {
 	return nil, errors.New("not implemented yet")
 }
-
-// Sourced from openshift image builder
-
-// TransformFileFunc is given a chance to transform an arbitrary input file.
-type TransformFileFunc func(h *tar.Header, r io.Reader) (data []byte, update bool, skip bool, err error)
-
-// filterArchive transforms the provided input archive to a new archive,
-// giving the fn a chance to transform arbitrary files.
-func filterArchive(r io.Reader, w io.Writer, fn TransformFileFunc) error {
-	tr := tar.NewReader(r)
-	tw := tar.NewWriter(w)
-
-	var body io.Reader = tr
-
-	for {
-		h, err := tr.Next()
-		if err == io.EOF {
-			return tw.Close()
-		}
-		if err != nil {
-			return err
-		}
-
-		name := h.Name
-		data, ok, skip, err := fn(h, tr)
-		logrus.Debugf("Transform %q -> %q: data=%t ok=%t skip=%t err=%v", name, h.Name, data != nil, ok, skip, err)
-		if err != nil {
-			return err
-		}
-		if skip {
-			continue
-		}
-		if ok {
-			h.Size = int64(len(data))
-			body = bytes.NewBuffer(data)
-		}
-		if err := tw.WriteHeader(h); err != nil {
-			return err
-		}
-		if _, err := io.Copy(tw, body); err != nil {
-			return err
-		}
-	}
-}
-
-func transformArchive(r io.Reader, compressed bool, fn TransformFileFunc) (io.Reader, error) {
-	var cwe error
-	pr, pw := io.Pipe()
-	go func() {
-		if compressed {
-			in, err := archive.DecompressStream(r)
-			if err != nil {
-				cwe = pw.CloseWithError(err)
-				return
-			}
-			r = in
-		}
-		err := filterArchive(r, pw, fn)
-		cwe = pw.CloseWithError(err)
-	}()
-	return pr, cwe
-}
diff --git a/pkg/varlinkapi/images.go b/pkg/varlinkapi/images.go
index 1dcfa2213..4bcf70b0d 100644
--- a/pkg/varlinkapi/images.go
+++ b/pkg/varlinkapi/images.go
@@ -23,7 +23,7 @@ import (
 	"github.com/containers/podman/v2/libpod"
 	"github.com/containers/podman/v2/libpod/define"
 	"github.com/containers/podman/v2/libpod/image"
-	"github.com/containers/podman/v2/pkg/channelwriter"
+	"github.com/containers/podman/v2/pkg/channel"
 	"github.com/containers/podman/v2/pkg/util"
 	iopodman "github.com/containers/podman/v2/pkg/varlink"
 	"github.com/containers/podman/v2/utils"
@@ -570,7 +570,7 @@ func (i *VarlinkAPI) Commit(call iopodman.VarlinkCall, name, imageName string, c
 		log      []string
 		mimeType string
 	)
-	output := channelwriter.NewChannelWriter()
+	output := channel.NewWriter(make(chan []byte))
 	channelClose := func() {
 		if err := output.Close(); err != nil {
 			logrus.Errorf("failed to close channel writer: %q", err)
@@ -704,7 +704,7 @@ func (i *VarlinkAPI) PullImage(call iopodman.VarlinkCall, name string, creds iop
 	if call.WantsMore() {
 		call.Continues = true
 	}
-	output := channelwriter.NewChannelWriter()
+	output := channel.NewWriter(make(chan []byte))
 	channelClose := func() {
 		if err := output.Close(); err != nil {
 			logrus.Errorf("failed to close channel writer: %q", err)
diff --git a/pkg/varlinkapi/util.go b/pkg/varlinkapi/util.go
index 748d8f9cc..7f96965f0 100644
--- a/pkg/varlinkapi/util.go
+++ b/pkg/varlinkapi/util.go
@@ -11,7 +11,7 @@ import (
 	"github.com/containers/buildah"
 	"github.com/containers/podman/v2/libpod"
 	"github.com/containers/podman/v2/libpod/define"
-	"github.com/containers/podman/v2/pkg/channelwriter"
+	"github.com/containers/podman/v2/pkg/channel"
 	iopodman "github.com/containers/podman/v2/pkg/varlink"
 	"github.com/containers/storage/pkg/archive"
 )
@@ -201,7 +201,7 @@ func makePsOpts(inOpts iopodman.PsOpts) PsOptions {
 // more.  it is capable of sending updates as the output writer gets them or append them
 // all to a log.  the chan error is the error from the libpod call so we can honor
 // and error event in that case.
-func forwardOutput(log []string, c chan error, wantsMore bool, output *channelwriter.Writer, reply func(br iopodman.MoreResponse) error) ([]string, error) {
+func forwardOutput(log []string, c chan error, wantsMore bool, output channel.WriteCloser, reply func(br iopodman.MoreResponse) error) ([]string, error) {
 	done := false
 	for {
 		select {
@@ -214,7 +214,7 @@ func forwardOutput(log []string, c chan error, wantsMore bool, output *channelwr
 			done = true
 		// if no error is found, we pull what we can from the log writer and
 		// append it to log string slice
-		case line := <-output.ByteChannel:
+		case line := <-output.Chan():
 			log = append(log, string(line))
 			// If the end point is being used in more mode, send what we have
 			if wantsMore {