Optionally use frontend inputs if provided

Dockerfile

@@ -1,11 +1,10 @@
-# syntax=tonistiigi/dockerfile:runmount20181002
-
-FROM golang:1.11-alpine AS build
+# syntax=docker/dockerfile-upstream:experimental
+FROM golang:1.12-alpine AS build
 WORKDIR /go/src/github.com/tonistiigi/buildkit-pack
-RUN apk add --no-cache file
+RUN apk add --no-cache file git
 RUN --mount=target=. --mount=target=/root/.cache,type=cache \
-  CGO_ENABLED=0 go build -o /out/pack ./cmd/pack && file /out/pack | grep "statically linked"
+  GO111MODULE=on CGO_ENABLED=0 go build -o /out/pack ./cmd/pack && file /out/pack | grep "statically linked"
 
 FROM scratch
 COPY --from=build /out/pack /bin/pack
-ENTRYPOINT ["/bin/pack"]
+ENTRYPOINT ["/bin/pack"]

build.go

@@ -8,6 +8,7 @@ import (
 	"github.com/moby/buildkit/client/llb"
 	"github.com/moby/buildkit/exporter/containerimage/exptypes"
 	"github.com/moby/buildkit/frontend/gateway/client"
+	gwpb "github.com/moby/buildkit/frontend/gateway/pb"
 	"github.com/moby/buildkit/solver/pb"
 	"github.com/pkg/errors"
 	"golang.org/x/sync/errgroup"
@@ -16,13 +17,15 @@ import (
 const (
 	keyStack          = "stack"
 	LocalNameContext  = "context"
+	InputNameManifest = "manifest"
 	buildArgPrefix    = "build-arg:"
 	keyBuildpackOrder = "buildpackOrder"
 	keySkipDetect     = "skipDetect"
 )
 
 func Build(ctx context.Context, c client.Client) (*client.Result, error) {
 	opts := c.BuildOpts().Opts
+	gwcaps := c.BuildOpts().Caps
 
 	// also accept build args from Moby
 	for k, v := range opts {
@@ -31,6 +34,39 @@ func Build(ctx context.Context, c client.Client) (*client.Result, error) {
 		}
 	}
 
+	var (
+		manifest llb.State
+		src      llb.State
+	)
+
+	// Use frontend input instead of `llb.Local` if supported by the gateway capabilities.
+	if (&gwcaps).Supports(gwpb.CapFrontendInputs) == nil {
+		inputs, err := c.Inputs(ctx)
+		if err != nil {
+			return nil, err
+		}
+
+		inputManifest, ok := inputs[InputNameManifest]
+		if ok {
+			manifest = inputManifest
+		}
+
+		inputContext, ok := inputs[LocalNameContext]
+		if ok {
+			src = inputContext
+		}
+
+	} else {
+		manifest = llb.Local(LocalNameContext,
+			llb.SessionID(c.BuildOpts().SessionID),
+			llb.IncludePatterns([]string{"manifest.yml"}),
+			llb.SharedKeyHint("manifest.yml"),
+			llb.WithCustomName("load manifest.yml"),
+		)
+
+		src = llb.Local(LocalNameContext, llb.SessionID(c.BuildOpts().SessionID), llb.SharedKeyHint("pack-src"))
+	}
+
 	stack := "cflinuxfs2"
 	if v, ok := opts[keyStack]; ok {
 		stack = v
@@ -41,7 +77,7 @@ func Build(ctx context.Context, c client.Client) (*client.Result, error) {
 		return nil, err
 	}
 
-	m, err := readManifest(ctx, c)
+	m, err := readManifest(ctx, c, manifest)
 	if err != nil {
 		return nil, err
 	}
@@ -74,9 +110,6 @@ func Build(ctx context.Context, c client.Client) (*client.Result, error) {
 
 	// TODO: read buildpacks and download directly
 
-	// TODO: git/http sources
-	src := llb.Local(LocalNameContext, llb.SessionID(c.BuildOpts().SessionID), llb.SharedKeyHint("pack-src"))
-
 	builderImage := llb.Image(buildName, llb.WithMetaResolver(c))
 
 	for k, v := range env {
@@ -126,7 +159,7 @@ func Build(ctx context.Context, c client.Client) (*client.Result, error) {
 
 	var config []byte
 	eg.Go(func() error {
-		_, c, err := c.ResolveImageConfig(ctx, runName, client.ResolveImageConfigOpt{})
+		_, c, err := c.ResolveImageConfig(ctx, runName, llb.ResolveImageConfigOpt{})
 		if err != nil {
 			return err
 		}

cmd/pack-cli/cli.go

@@ -124,13 +124,19 @@ func newSolveOpt(clicontext *cli.Context, w io.WriteCloser) (*client.SolveOpt, e
 	// }
 
 	return &client.SolveOpt{
-		Exporter: "docker",
-		ExporterAttrs: map[string]string{
-			"name": clicontext.String("tag"),
+		Exports: []client.ExportEntry{
+			{
+				Type: client.ExporterDocker,
+				Attrs: map[string]string{
+					"name": clicontext.String("tag"),
+				},
+				Output: func(_ map[string]string) (io.WriteCloser, error) {
+					return w, nil
+				},
+			},
 		},
-		ExporterOutput: w,
-		LocalDirs:      localDirs,
-		FrontendAttrs:  frontendAttrs,
+		LocalDirs:     localDirs,
+		FrontendAttrs: frontendAttrs,
 	}, nil
 }
 

go.mod

@@ -0,0 +1,41 @@
+module github.com/tonistiigi/buildkit-pack
+
+go 1.12
+
+require (
+	github.com/Microsoft/go-winio v0.4.14
+	github.com/containerd/console v0.0.0-20181022165439-0650fd9eeb50
+	github.com/containerd/containerd v1.4.0-0.20191014053712-acdcf13d5eaf
+	github.com/containerd/continuity v0.0.0-20200107194136-26c1120b8d41
+	github.com/docker/distribution v2.7.1-0.20190205005809-0d3efadf0154+incompatible
+	github.com/docker/docker v1.14.0-0.20190319215453-e7b5f7dbe98c
+	github.com/gogo/googleapis v1.1.0
+	github.com/gogo/protobuf v1.2.0
+	github.com/golang/protobuf v1.2.0
+	github.com/google/shlex v0.0.0-20150127133951-6f45313302b9
+	github.com/grpc-ecosystem/grpc-opentracing v0.0.0-20180507213350-8e809c8a8645
+	github.com/moby/buildkit v0.0.0-20181003224033-f07efb78e3f1
+	github.com/morikuni/aec v0.0.0-20170113033406-39771216ff4c
+	github.com/opencontainers/go-digest v1.0.0-rc1
+	github.com/opencontainers/image-spec v1.0.1
+	github.com/opentracing/opentracing-go v0.0.0-20171003133519-1361b9cd60be
+	github.com/pkg/errors v0.8.1
+	github.com/sirupsen/logrus v1.4.1
+	github.com/tonistiigi/fsutil v0.0.0-20191018213012-0f039a052ca1
+	github.com/tonistiigi/units v0.0.0-20180711220420-6950e57a87ea
+	github.com/urfave/cli v0.0.0-20171014202726-7bc6a0acffa5
+	golang.org/x/net v0.0.0-20190522155817-f3200d17e092
+	golang.org/x/sync v0.0.0-20190423024810-112230192c58
+	golang.org/x/sys v0.0.0-20190812073006-9eafafc0a87e
+	golang.org/x/text v0.3.0
+	golang.org/x/time v0.0.0-20161028155119-f51c12702a4d
+	google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8
+	google.golang.org/grpc v1.23.0
+	gopkg.in/yaml.v2 v2.2.2
+)
+
+replace github.com/moby/buildkit => github.com/hinshun/buildkit v0.0.0-20200124224350-99d18890d310
+
+replace github.com/hashicorp/go-immutable-radix => github.com/tonistiigi/go-immutable-radix v0.0.0-20170803185627-826af9ccf0fe
+
+replace github.com/jaguilar/vt100 => github.com/tonistiigi/vt100 v0.0.0-20190402012908-ad4c4a574305