deploytool: Add README.md, migrate docs to it.

deploytool/cmd/staging.go

Index: deploytool/cmd/staging.go
diff --git a/deploytool/cmd/staging.go b/deploytool/cmd/staging.go
deleted file mode 100644
index f35c96e7a7d2c2199438361285c674307569bde1..0000000000000000000000000000000000000000
--- a/deploytool/cmd/staging.go
+++ /dev/null
@@ -1,83 +0,0 @@
-// Copyright 2016 The LUCI Authors. All rights reserved.
-// Use of this source code is governed under the Apache License, Version 2.0
-// that can be found in the LICENSE file.
-
-package main
-
-import (
-	"strings"
-
-	"github.com/luci/luci-go/common/errors"
-	"github.com/luci/luci-go/deploytool/managedfs"
-)
-
-// stageGoPath creates a GOPATH-compatible directory consisting of all of the
-// GOPATHs configured in the supplied components sources. The path begins with
-// "src/", and is rooted in the supplied root.
-func stageGoPath(w *work, comp *layoutDeploymentComponent, root *managedfs.Dir) error {
-	// Build our GoPath sources. To do this, we will build subdirectories under
-	// "src" for the various GoPath components, then symlink the last directory
-	// component to the actual GOPATH root.
-	//
-	// We need to detect path conflicts where one GOPATH checks out into the
-	// parent of another GOPATH, e.g.:
-	// /foo/bar/baz => A
-	// /foo/bar => B
-	//
-	// We do this by checking intermediate Go paths against our deployment plan
-	// incrementally.
-	dirs := make(map[string]struct{})
-	build := make(map[string]string)
-	for _, src := range comp.sources {
-		if src.InitResult == nil {
-			continue
-		}
-
-		for _, gopath := range src.InitResult.GoPath {
-			// Make sure our Go package isn't a directory.
-			if _, ok := dirs[gopath.GoPackage]; ok {
-				return errors.Reason("GOPATH %(package)q is both a package and directory").
-					D("package", gopath.GoPackage).Err()
-			}
-
-			// Check intermediate paths to make sure there isn't a deployment
-			// conflict.
-			pkgParts := splitGoPackage(gopath.GoPackage)
-			for _, parentPkg := range pkgParts[:len(pkgParts)-1] {
-				if _, ok := build[parentPkg]; ok {
-					return errors.Reason("GOPATH %(package)q is both a package and directory").
-						D("package", parentPkg).Err()
-				}
-				dirs[parentPkg] = struct{}{}
-			}
-
-			// Everything checks out, add this link.
-			build[gopath.GoPackage] = src.pathTo(gopath.Path, "")
-		}
-	}
-
-	srcDir, err := root.EnsureDirectory("src")
-	if err != nil {
-		return err
-	}
-
-	for pkg, src := range build {
-		var (
-			pkgComponents = strings.Split(pkg, "/")
-			d             = srcDir
-		)
-		for _, comp := range pkgComponents[:len(pkgComponents)-1] {
-			var err error
-			d, err = d.EnsureDirectory(comp)
-			if err != nil {
-				return errors.Annotate(err).Reason("could not create GOPATH parent directory [%(path)s]").
-					D("path", d).Err()
-			}
-		}
-		link := d.File(pkgComponents[len(pkgComponents)-1])
-		if err := link.SymlinkFrom(src, true); err != nil {
-			return errors.Annotate(err).Reason("failed to create GOPATH link").Err()
-		}
-	}
-	return nil
-}