gopkg.in/tools/godep.v47@v47.0.0-20160112223013-b922ec76f713/go.go (about) 1 package main 2 3 import ( 4 "fmt" 5 "log" 6 "os" 7 "os/exec" 8 "path/filepath" 9 "strings" 10 ) 11 12 var cmdGo = &Command{ 13 Name: "go", 14 Args: "command [arguments]", 15 Short: "run the go tool with saved dependencies", 16 Long: ` 17 Go runs the go tool with a modified GOPATH giving access to 18 dependencies saved in Godeps. 19 20 Any go tool command can run this way, but "godep go get" 21 is unnecessary and has been disabled. Instead, use 22 "godep go install". 23 `, 24 Run: runGo, 25 } 26 27 // Find the godep GOPATH for this file tree and run the go tool. 28 func runGo(cmd *Command, args []string) { 29 gopath := prepareGopath() 30 if s := os.Getenv("GOPATH"); s != "" { 31 gopath += string(os.PathListSeparator) + os.Getenv("GOPATH") 32 } 33 if len(args) > 0 && args[0] == "get" { 34 log.Printf("invalid subcommand: %q", "go get") 35 fmt.Fprintln(os.Stderr, "Use 'godep go install' instead.") 36 fmt.Fprintln(os.Stderr, "Run 'godep help go' for usage.") 37 os.Exit(2) 38 } 39 c := exec.Command("go", args...) 40 c.Env = append(envNoGopath(), "GOPATH="+gopath) 41 c.Stdin = os.Stdin 42 c.Stdout = os.Stdout 43 c.Stderr = os.Stderr 44 err := c.Run() 45 if err != nil { 46 log.Fatalln("go", err) 47 } 48 } 49 50 // prepareGopath reads dependency information from the filesystem 51 // entry name, fetches any necessary code, and returns a gopath 52 // causing the specified dependencies to be used. 53 func prepareGopath() (gopath string) { 54 dir, isDir := findGodeps() 55 if dir == "" { 56 log.Fatalln("No Godeps found (or in any parent directory)") 57 } 58 if !isDir { 59 log.Fatalln(strings.TrimSpace(needSource)) 60 } 61 return filepath.Join(dir, "Godeps", "_workspace") 62 } 63 64 // findGodeps looks for a directory entry "Godeps" in the 65 // current directory or any parent, and returns the containing 66 // directory and whether the entry itself is a directory. 67 // If Godeps can't be found, findGodeps returns "". 68 // For any other error, it exits the program. 69 func findGodeps() (dir string, isDir bool) { 70 wd, err := os.Getwd() 71 if err != nil { 72 log.Fatalln(err) 73 } 74 return findInParents(wd, "Godeps") 75 } 76 77 // isRoot returns true iff a path is a root. 78 // On Unix: "/". 79 // On Windows: "C:\", "D:\", ... 80 func isRoot(p string) bool { 81 p = filepath.Clean(p) 82 volume := filepath.VolumeName(p) 83 84 p = strings.TrimPrefix(p, volume) 85 p = filepath.ToSlash(p) 86 87 return p == "/" 88 } 89 90 // findInParents returns the path to the directory containing name 91 // in dir or any ancestor, and whether name itself is a directory. 92 // If name cannot be found, findInParents returns the empty string. 93 func findInParents(dir, name string) (container string, isDir bool) { 94 for { 95 fi, err := os.Stat(filepath.Join(dir, name)) 96 if os.IsNotExist(err) && isRoot(dir) { 97 return "", false 98 } 99 if os.IsNotExist(err) { 100 dir = filepath.Dir(dir) 101 continue 102 } 103 if err != nil { 104 log.Fatalln(err) 105 } 106 return dir, fi.IsDir() 107 } 108 } 109 110 func envNoGopath() (a []string) { 111 for _, s := range os.Environ() { 112 if !strings.HasPrefix(s, "GOPATH=") { 113 a = append(a, s) 114 } 115 } 116 return a 117 } 118 119 const needSource = ` 120 outdated Godeps missing source code 121 122 This dependency list was created with an old version of godep. 123 124 To work around this, you have two options: 125 1. Run 'godep restore', and try again. 126 2. Ask the maintainer to switch to a newer version of godep, 127 then try again with the updated package. 128 `