1 files changed, 342 insertions, 0 deletions
diff --git a/vendor/google.golang.org/appengine/cmd/aebundler/aebundler.go b/vendor/google.golang.org/appengine/cmd/aebundler/aebundler.go
new file mode 100644
index 000000000..c66849e83
--- /dev/null
+++ b/vendor/google.golang.org/appengine/cmd/aebundler/aebundler.go
@@ -0,0 +1,342 @@
+// Copyright 2015 Google Inc. All rights reserved.
+// Use of this source code is governed by the Apache 2.0
+// license that can be found in the LICENSE file.
+
+// Program aebundler turns a Go app into a fully self-contained tar file.
+// The app and its subdirectories (if any) are placed under "."
+// and the dependencies from $GOPATH are placed under ./_gopath/src.
+// A main func is synthesized if one does not exist.
+//
+// A sample Dockerfile to be used with this bundler could look like this:
+//     FROM gcr.io/google-appengine/go-compat
+//     ADD . /app
+//     RUN GOPATH=/app/_gopath go build -tags appenginevm -o /app/_ah/exe
+package main
+
+import (
+	"archive/tar"
+	"flag"
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/parser"
+	"go/token"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+var (
+	output  = flag.String("o", "", "name of output tar file or '-' for stdout")
+	rootDir = flag.String("root", ".", "directory name of application root")
+	vm      = flag.Bool("vm", true, `bundle an app for App Engine "flexible environment"`)
+
+	skipFiles = map[string]bool{
+		".git":        true,
+		".gitconfig":  true,
+		".hg":         true,
+		".travis.yml": true,
+	}
+)
+
+const (
+	newMain = `package main
+import "google.golang.org/appengine"
+func main() {
+	appengine.Main()
+}
+`
+)
+
+func usage() {
+	fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "\t%s -o <file.tar|->\tBundle app to named tar file or stdout\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "\noptional arguments:\n")
+	flag.PrintDefaults()
+}
+
+func main() {
+	flag.Usage = usage
+	flag.Parse()
+
+	var tags []string
+	if *vm {
+		tags = append(tags, "appenginevm")
+	} else {
+		tags = append(tags, "appengine")
+	}
+
+	tarFile := *output
+	if tarFile == "" {
+		usage()
+		errorf("Required -o flag not specified.")
+	}
+
+	app, err := analyze(tags)
+	if err != nil {
+		errorf("Error analyzing app: %v", err)
+	}
+	if err := app.bundle(tarFile); err != nil {
+		errorf("Unable to bundle app: %v", err)
+	}
+}
+
+// errorf prints the error message and exits.
+func errorf(format string, a ...interface{}) {
+	fmt.Fprintf(os.Stderr, "aebundler: "+format+"\n", a...)
+	os.Exit(1)
+}
+
+type app struct {
+	hasMain  bool
+	appFiles []string
+	imports  map[string]string
+}
+
+// analyze checks the app for building with the given build tags and returns hasMain,
+// app files, and a map of full directory import names to original import names.
+func analyze(tags []string) (*app, error) {
+	ctxt := buildContext(tags)
+	hasMain, appFiles, err := checkMain(ctxt)
+	if err != nil {
+		return nil, err
+	}
+	gopath := filepath.SplitList(ctxt.GOPATH)
+	im, err := imports(ctxt, *rootDir, gopath)
+	return &app{
+		hasMain:  hasMain,
+		appFiles: appFiles,
+		imports:  im,
+	}, err
+}
+
+// buildContext returns the context for building the source.
+func buildContext(tags []string) *build.Context {
+	return &build.Context{
+		GOARCH:    build.Default.GOARCH,
+		GOOS:      build.Default.GOOS,
+		GOROOT:    build.Default.GOROOT,
+		GOPATH:    build.Default.GOPATH,
+		Compiler:  build.Default.Compiler,
+		BuildTags: append(build.Default.BuildTags, tags...),
+	}
+}
+
+// bundle bundles the app into the named tarFile ("-"==stdout).
+func (s *app) bundle(tarFile string) (err error) {
+	var out io.Writer
+	if tarFile == "-" {
+		out = os.Stdout
+	} else {
+		f, err := os.Create(tarFile)
+		if err != nil {
+			return err
+		}
+		defer func() {
+			if cerr := f.Close(); err == nil {
+				err = cerr
+			}
+		}()
+		out = f
+	}
+	tw := tar.NewWriter(out)
+
+	for srcDir, importName := range s.imports {
+		dstDir := "_gopath/src/" + importName
+		if err = copyTree(tw, dstDir, srcDir); err != nil {
+			return fmt.Errorf("unable to copy directory %v to %v: %v", srcDir, dstDir, err)
+		}
+	}
+	if err := copyTree(tw, ".", *rootDir); err != nil {
+		return fmt.Errorf("unable to copy root directory to /app: %v", err)
+	}
+	if !s.hasMain {
+		if err := synthesizeMain(tw, s.appFiles); err != nil {
+			return fmt.Errorf("unable to synthesize new main func: %v", err)
+		}
+	}
+
+	if err := tw.Close(); err != nil {
+		return fmt.Errorf("unable to close tar file %v: %v", tarFile, err)
+	}
+	return nil
+}
+
+// synthesizeMain generates a new main func and writes it to the tarball.
+func synthesizeMain(tw *tar.Writer, appFiles []string) error {
+	appMap := make(map[string]bool)
+	for _, f := range appFiles {
+		appMap[f] = true
+	}
+	var f string
+	for i := 0; i < 100; i++ {
+		f = fmt.Sprintf("app_main%d.go", i)
+		if !appMap[filepath.Join(*rootDir, f)] {
+			break
+		}
+	}
+	if appMap[filepath.Join(*rootDir, f)] {
+		return fmt.Errorf("unable to find unique name for %v", f)
+	}
+	hdr := &tar.Header{
+		Name: f,
+		Mode: 0644,
+		Size: int64(len(newMain)),
+	}
+	if err := tw.WriteHeader(hdr); err != nil {
+		return fmt.Errorf("unable to write header for %v: %v", f, err)
+	}
+	if _, err := tw.Write([]byte(newMain)); err != nil {
+		return fmt.Errorf("unable to write %v to tar file: %v", f, err)
+	}
+	return nil
+}
+
+// imports returns a map of all import directories (recursively) used by the app.
+// The return value maps full directory names to original import names.
+func imports(ctxt *build.Context, srcDir string, gopath []string) (map[string]string, error) {
+	pkg, err := ctxt.ImportDir(srcDir, 0)
+	if err != nil {
+		return nil, fmt.Errorf("unable to analyze source: %v", err)
+	}
+
+	// Resolve all non-standard-library imports
+	result := make(map[string]string)
+	for _, v := range pkg.Imports {
+		if !strings.Contains(v, ".") {
+			continue
+		}
+		src, err := findInGopath(v, gopath)
+		if err != nil {
+			return nil, fmt.Errorf("unable to find import %v in gopath %v: %v", v, gopath, err)
+		}
+		result[src] = v
+		im, err := imports(ctxt, src, gopath)
+		if err != nil {
+			return nil, fmt.Errorf("unable to parse package %v: %v", src, err)
+		}
+		for k, v := range im {
+			result[k] = v
+		}
+	}
+	return result, nil
+}
+
+// findInGopath searches the gopath for the named import directory.
+func findInGopath(dir string, gopath []string) (string, error) {
+	for _, v := range gopath {
+		dst := filepath.Join(v, "src", dir)
+		if _, err := os.Stat(dst); err == nil {
+			return dst, nil
+		}
+	}
+	return "", fmt.Errorf("unable to find package %v in gopath %v", dir, gopath)
+}
+
+// copyTree copies srcDir to tar file dstDir, ignoring skipFiles.
+func copyTree(tw *tar.Writer, dstDir, srcDir string) error {
+	entries, err := ioutil.ReadDir(srcDir)
+	if err != nil {
+		return fmt.Errorf("unable to read dir %v: %v", srcDir, err)
+	}
+	for _, entry := range entries {
+		n := entry.Name()
+		if skipFiles[n] {
+			continue
+		}
+		s := filepath.Join(srcDir, n)
+		d := filepath.Join(dstDir, n)
+		if entry.IsDir() {
+			if err := copyTree(tw, d, s); err != nil {
+				return fmt.Errorf("unable to copy dir %v to %v: %v", s, d, err)
+			}
+			continue
+		}
+		if err := copyFile(tw, d, s); err != nil {
+			return fmt.Errorf("unable to copy dir %v to %v: %v", s, d, err)
+		}
+	}
+	return nil
+}
+
+// copyFile copies src to tar file dst.
+func copyFile(tw *tar.Writer, dst, src string) error {
+	s, err := os.Open(src)
+	if err != nil {
+		return fmt.Errorf("unable to open %v: %v", src, err)
+	}
+	defer s.Close()
+	fi, err := s.Stat()
+	if err != nil {
+		return fmt.Errorf("unable to stat %v: %v", src, err)
+	}
+
+	hdr, err := tar.FileInfoHeader(fi, dst)
+	if err != nil {
+		return fmt.Errorf("unable to create tar header for %v: %v", dst, err)
+	}
+	hdr.Name = dst
+	if err := tw.WriteHeader(hdr); err != nil {
+		return fmt.Errorf("unable to write header for %v: %v", dst, err)
+	}
+	_, err = io.Copy(tw, s)
+	if err != nil {
+		return fmt.Errorf("unable to copy %v to %v: %v", src, dst, err)
+	}
+	return nil
+}
+
+// checkMain verifies that there is a single "main" function.
+// It also returns a list of all Go source files in the app.
+func checkMain(ctxt *build.Context) (bool, []string, error) {
+	pkg, err := ctxt.ImportDir(*rootDir, 0)
+	if err != nil {
+		return false, nil, fmt.Errorf("unable to analyze source: %v", err)
+	}
+	if !pkg.IsCommand() {
+		errorf("Your app's package needs to be changed from %q to \"main\".\n", pkg.Name)
+	}
+	// Search for a "func main"
+	var hasMain bool
+	var appFiles []string
+	for _, f := range pkg.GoFiles {
+		n := filepath.Join(*rootDir, f)
+		appFiles = append(appFiles, n)
+		if hasMain, err = readFile(n); err != nil {
+			return false, nil, fmt.Errorf("error parsing %q: %v", n, err)
+		}
+	}
+	return hasMain, appFiles, nil
+}
+
+// isMain returns whether the given function declaration is a main function.
+// Such a function must be called "main", not have a receiver, and have no arguments or return types.
+func isMain(f *ast.FuncDecl) bool {
+	ft := f.Type
+	return f.Name.Name == "main" && f.Recv == nil && ft.Params.NumFields() == 0 && ft.Results.NumFields() == 0
+}
+
+// readFile reads and parses the Go source code file and returns whether it has a main function.
+func readFile(filename string) (hasMain bool, err error) {
+	var src []byte
+	src, err = ioutil.ReadFile(filename)
+	if err != nil {
+		return
+	}
+	fset := token.NewFileSet()
+	file, err := parser.ParseFile(fset, filename, src, 0)
+	for _, decl := range file.Decls {
+		funcDecl, ok := decl.(*ast.FuncDecl)
+		if !ok {
+			continue
+		}
+		if !isMain(funcDecl) {
+			continue
+		}
+		hasMain = true
+		break
+	}
+	return
+}