golang.org/x/tools@v0.21.1-0.20240520172518-788d39e776b1/internal/proxydir/proxydir.go (about)

     1  // Copyright 2020 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // Package proxydir provides functions for writing module data to a directory
     6  // in proxy format, so that it can be used as a module proxy by setting
     7  // GOPROXY="file://<dir>".
     8  package proxydir
     9  
    10  import (
    11  	"archive/zip"
    12  	"fmt"
    13  	"io"
    14  	"os"
    15  	"path/filepath"
    16  	"strings"
    17  
    18  	"golang.org/x/tools/internal/testenv"
    19  )
    20  
    21  // WriteModuleVersion creates a directory in the proxy dir for a module.
    22  func WriteModuleVersion(rootDir, module, ver string, files map[string][]byte) (rerr error) {
    23  	dir := filepath.Join(rootDir, module, "@v")
    24  	if err := os.MkdirAll(dir, 0755); err != nil {
    25  		return err
    26  	}
    27  
    28  	// The go command checks for versions by looking at the "list" file.  Since
    29  	// we are supporting multiple versions, create this file if it does not exist
    30  	// or append the version number to the preexisting file.
    31  	f, err := os.OpenFile(filepath.Join(dir, "list"), os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
    32  	if err != nil {
    33  		return err
    34  	}
    35  	defer checkClose("list file", f, &rerr)
    36  	if _, err := f.WriteString(ver + "\n"); err != nil {
    37  		return err
    38  	}
    39  
    40  	// Serve the go.mod file on the <version>.mod url, if it exists. Otherwise,
    41  	// serve a stub.
    42  	modContents, ok := files["go.mod"]
    43  	if !ok {
    44  		modContents = []byte("module " + module)
    45  	}
    46  	if err := os.WriteFile(filepath.Join(dir, ver+".mod"), modContents, 0644); err != nil {
    47  		return err
    48  	}
    49  
    50  	// info file, just the bare bones.
    51  	infoContents := []byte(fmt.Sprintf(`{"Version": "%v", "Time":"2017-12-14T13:08:43Z"}`, ver))
    52  	if err := os.WriteFile(filepath.Join(dir, ver+".info"), infoContents, 0644); err != nil {
    53  		return err
    54  	}
    55  
    56  	// zip of all the source files.
    57  	f, err = os.OpenFile(filepath.Join(dir, ver+".zip"), os.O_CREATE|os.O_WRONLY, 0644)
    58  	if err != nil {
    59  		return err
    60  	}
    61  	defer checkClose("zip file", f, &rerr)
    62  	z := zip.NewWriter(f)
    63  	defer checkClose("zip writer", z, &rerr)
    64  	for name, contents := range files {
    65  		zf, err := z.Create(module + "@" + ver + "/" + name)
    66  		if err != nil {
    67  			return err
    68  		}
    69  		if _, err := zf.Write(contents); err != nil {
    70  			return err
    71  		}
    72  	}
    73  
    74  	return nil
    75  }
    76  
    77  func checkClose(name string, closer io.Closer, err *error) {
    78  	if cerr := closer.Close(); cerr != nil && *err == nil {
    79  		*err = fmt.Errorf("closing %s: %v", name, cerr)
    80  	}
    81  }
    82  
    83  // ToURL returns the file uri for a proxy directory.
    84  func ToURL(dir string) string {
    85  	if testenv.Go1Point() >= 13 {
    86  		// file URLs on Windows must start with file:///. See golang.org/issue/6027.
    87  		path := filepath.ToSlash(dir)
    88  		if !strings.HasPrefix(path, "/") {
    89  			path = "/" + path
    90  		}
    91  		return "file://" + path
    92  	} else {
    93  		// Prior to go1.13, the Go command on Windows only accepted GOPROXY file URLs
    94  		// of the form file://C:/path/to/proxy. This was incorrect: when parsed, "C:"
    95  		// is interpreted as the host. See golang.org/issue/6027. This has been
    96  		// fixed in go1.13, but we emit the old format for old releases.
    97  		return "file://" + filepath.ToSlash(dir)
    98  	}
    99  }