bake: update ReadRemoteFiles to use buildkit api

Signed-off-by: Justin Chadwell <me@jedevc.com>

vendor/github.com/moby/buildkit/frontend/dockerui/context.go

@@ -0,0 +1,194 @@
+package dockerui
+
+import (
+	"archive/tar"
+	"bytes"
+	"context"
+	"path/filepath"
+	"regexp"
+	"strconv"
+
+	"github.com/moby/buildkit/client/llb"
+	"github.com/moby/buildkit/frontend/gateway/client"
+	gwpb "github.com/moby/buildkit/frontend/gateway/pb"
+	"github.com/moby/buildkit/util/gitutil"
+	"github.com/pkg/errors"
+)
+
+const (
+	DefaultLocalNameContext    = "context"
+	DefaultLocalNameDockerfile = "dockerfile"
+	DefaultDockerfileName      = "Dockerfile"
+	DefaultDockerignoreName    = ".dockerignore"
+	EmptyImageName             = "scratch"
+)
+
+const (
+	keyFilename       = "filename"
+	keyContextSubDir  = "contextsubdir"
+	keyNameContext    = "contextkey"
+	keyNameDockerfile = "dockerfilekey"
+)
+
+var httpPrefix = regexp.MustCompile(`^https?://`)
+
+type buildContext struct {
+	context              *llb.State // set if not local
+	dockerfile           *llb.State // override remoteContext if set
+	contextLocalName     string
+	dockerfileLocalName  string
+	filename             string
+	forceLocalDockerfile bool
+}
+
+func (bc *Client) marshalOpts() []llb.ConstraintsOpt {
+	return []llb.ConstraintsOpt{llb.WithCaps(bc.bopts.Caps)}
+}
+
+func (bc *Client) initContext(ctx context.Context) (*buildContext, error) {
+	opts := bc.bopts.Opts
+	gwcaps := bc.bopts.Caps
+
+	localNameContext := DefaultLocalNameContext
+	if v, ok := opts[keyNameContext]; ok {
+		localNameContext = v
+	}
+
+	bctx := &buildContext{
+		contextLocalName:    DefaultLocalNameContext,
+		dockerfileLocalName: DefaultLocalNameDockerfile,
+		filename:            DefaultDockerfileName,
+	}
+
+	if v, ok := opts[keyFilename]; ok {
+		bctx.filename = v
+	}
+
+	if v, ok := opts[keyNameDockerfile]; ok {
+		bctx.forceLocalDockerfile = true
+		bctx.dockerfileLocalName = v
+	}
+
+	keepGit := false
+	if v, err := strconv.ParseBool(opts[keyContextKeepGitDirArg]); err == nil {
+		keepGit = v
+	}
+	if st, ok := DetectGitContext(opts[localNameContext], keepGit); ok {
+		bctx.context = st
+		bctx.dockerfile = st
+	} else if st, filename, ok := DetectHTTPContext(opts[localNameContext]); ok {
+		def, err := st.Marshal(ctx, bc.marshalOpts()...)
+		if err != nil {
+			return nil, errors.Wrapf(err, "failed to marshal httpcontext")
+		}
+		res, err := bc.client.Solve(ctx, client.SolveRequest{
+			Definition: def.ToPB(),
+		})
+		if err != nil {
+			return nil, errors.Wrapf(err, "failed to resolve httpcontext")
+		}
+
+		ref, err := res.SingleRef()
+		if err != nil {
+			return nil, err
+		}
+
+		dt, err := ref.ReadFile(ctx, client.ReadRequest{
+			Filename: filename,
+			Range: &client.FileRange{
+				Length: 1024,
+			},
+		})
+		if err != nil {
+			return nil, errors.Wrapf(err, "failed to read downloaded context")
+		}
+		if isArchive(dt) {
+			bc := llb.Scratch().File(llb.Copy(*st, filepath.Join("/", filename), "/", &llb.CopyInfo{
+				AttemptUnpack: true,
+			}))
+			bctx.context = &bc
+		} else {
+			bctx.filename = filename
+			bctx.context = st
+		}
+		bctx.dockerfile = bctx.context
+	} else if (&gwcaps).Supports(gwpb.CapFrontendInputs) == nil {
+		inputs, err := bc.client.Inputs(ctx)
+		if err != nil {
+			return nil, errors.Wrapf(err, "failed to get frontend inputs")
+		}
+
+		if !bctx.forceLocalDockerfile {
+			inputDockerfile, ok := inputs[bctx.dockerfileLocalName]
+			if ok {
+				bctx.dockerfile = &inputDockerfile
+			}
+		}
+
+		inputCtx, ok := inputs[DefaultLocalNameContext]
+		if ok {
+			bctx.context = &inputCtx
+		}
+	}
+
+	if bctx.context != nil {
+		if sub, ok := opts[keyContextSubDir]; ok {
+			bctx.context = scopeToSubDir(bctx.context, sub)
+		}
+	}
+
+	return bctx, nil
+}
+
+func DetectGitContext(ref string, keepGit bool) (*llb.State, bool) {
+	g, err := gitutil.ParseGitRef(ref)
+	if err != nil {
+		return nil, false
+	}
+	commit := g.Commit
+	if g.SubDir != "" {
+		commit += ":" + g.SubDir
+	}
+	gitOpts := []llb.GitOption{WithInternalName("load git source " + ref)}
+	if keepGit {
+		gitOpts = append(gitOpts, llb.KeepGitDir())
+	}
+
+	st := llb.Git(g.Remote, commit, gitOpts...)
+	return &st, true
+}
+
+func DetectHTTPContext(ref string) (*llb.State, string, bool) {
+	filename := "context"
+	if httpPrefix.MatchString(ref) {
+		st := llb.HTTP(ref, llb.Filename(filename), WithInternalName("load remote build context"))
+		return &st, filename, true
+	}
+	return nil, "", false
+}
+
+func isArchive(header []byte) bool {
+	for _, m := range [][]byte{
+		{0x42, 0x5A, 0x68},                   // bzip2
+		{0x1F, 0x8B, 0x08},                   // gzip
+		{0xFD, 0x37, 0x7A, 0x58, 0x5A, 0x00}, // xz
+	} {
+		if len(header) < len(m) {
+			continue
+		}
+		if bytes.Equal(m, header[:len(m)]) {
+			return true
+		}
+	}
+
+	r := tar.NewReader(bytes.NewBuffer(header))
+	_, err := r.Next()
+	return err == nil
+}
+
+func scopeToSubDir(c *llb.State, dir string) *llb.State {
+	bc := llb.Scratch().File(llb.Copy(*c, dir, "/", &llb.CopyInfo{
+		CopyDirContentsOnly: true,
+	}))
+	return &bc
+}