goproxytest: support fallback from txtar to reading from directory of files (#43)

Author: myitcv

goproxytest/proxy.go

@@ -3,22 +3,21 @@
 // license that can be found in the LICENSE file.
 
 /*
-Package goproxytest serves Go modules from a proxy
-server designed to run on localhost during tests, both to make tests avoid
-requiring specific network servers and also to make them
-significantly faster.
+Package goproxytest serves Go modules from a proxy server designed to run on
+localhost during tests, both to make tests avoid requiring specific network
+servers and also to make them significantly faster.
 
-Each module archive is named path_vers.txt, where slashes in path
-have been replaced with underscores. The archive must contain
-two files ".info" and ".mod", to be served as the info and mod files
-in the proxy protocol (see https://research.swtch.com/vgo-module).
-The remaining files are served as the content of the module zip file.
-The path@vers prefix required of files in the zip file is added
-automatically by the proxy: the files in the archive have names without
-the prefix, like plain "go.mod", "x.go", and so on.
+Each module archive is either a file named path_vers.txt or a directory named
+path_vers, where slashes in path have been replaced with underscores. The
+archive or directory must contain two files ".info" and ".mod", to be served as
+the info and mod files in the proxy protocol (see
+https://research.swtch.com/vgo-module).  The remaining files are served as the
+content of the module zip file.  The path@vers prefix required of files in the
+zip file is added automatically by the proxy: the files in the archive have
+names without the prefix, like plain "go.mod", "x.go", and so on.
 
-See ../cmd/txtar-addmod and ../cmd/txtar-savedir for tools
-generate txtar files, although it's fine to write them by hand.
+See ../cmd/txtar-addmod and ../cmd/txtar-savedir for tools generate txtar
+files, although it's fine to write them by hand.
 */
 package goproxytest
 
@@ -92,7 +91,7 @@ func (srv *Server) readModList() error {
 	}
 	for _, info := range infos {
 		name := info.Name()
-		if !strings.HasSuffix(name, ".txt") {
+		if !strings.HasSuffix(name, ".txt") && !info.IsDir() {
 			continue
 		}
 		name = strings.TrimSuffix(name, ".txt")
@@ -275,6 +274,34 @@ func (srv *Server) readArchive(path, vers string) *txtar.Archive {
 	name := filepath.Join(srv.dir, prefix+"_"+encVers+".txt")
 	a := srv.archiveCache.Do(name, func() interface{} {
 		a, err := txtar.ParseFile(name)
+		if os.IsNotExist(err) {
+			// we fallback to trying a directory
+			name = strings.TrimSuffix(name, ".txt")
+
+			a = new(txtar.Archive)
+
+			err = filepath.Walk(name, func(path string, info os.FileInfo, err error) error {
+				if err != nil {
+					return err
+				}
+				if path == name && !info.IsDir() {
+					return fmt.Errorf("expected a directory root")
+				}
+				if info.IsDir() {
+					return nil
+				}
+				arpath := filepath.ToSlash(strings.TrimPrefix(path, name+string(os.PathSeparator)))
+				data, err := ioutil.ReadFile(path)
+				if err != nil {
+					return err
+				}
+				a.Files = append(a.Files, txtar.File{
+					Name: arpath,
+					Data: data,
+				})
+				return nil
+			})
+		}
 		if err != nil {
 			if !os.IsNotExist(err) {
 				fmt.Fprintf(os.Stderr, "go proxy: %v\n", err)

goproxytest/proxy_test.go

@@ -0,0 +1,34 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package goproxytest_test
+
+import (
+	"path/filepath"
+	"testing"
+
+	"github.com/rogpeppe/go-internal/goproxytest"
+	"github.com/rogpeppe/go-internal/gotooltest"
+	"github.com/rogpeppe/go-internal/testscript"
+)
+
+func TestScripts(t *testing.T) {
+	srv, err := goproxytest.NewServer(filepath.Join("testdata", "mod"), "")
+	if err != nil {
+		t.Fatalf("cannot start proxy: %v", err)
+	}
+	p := testscript.Params{
+		Dir: "testdata",
+		Setup: func(e *testscript.Env) error {
+			e.Vars = append(e.Vars,
+				"GOPROXY="+srv.URL,
+			)
+			return nil
+		},
+	}
+	if err := gotooltest.Setup(&p); err != nil {
+		t.Fatal(err)
+	}
+	testscript.Run(t, p)
+}

goproxytest/testdata/list.txt

@@ -0,0 +1,12 @@
+# prior to go 1.12 you cannot list a module without a requirement
+[!go1.12] go get fruit.com
+
+go list -m -versions fruit.com
+stdout 'v1.0.0 v1.1.0'
+
+go get -m [email protected]
+go get -m [email protected]
+
+-- go.mod --
+module mod
+

goproxytest/testdata/mod/fruit.com_v1.0.0.txt

@@ -0,0 +1,13 @@
+-- .mod --
+module fruit.com
+
+-- .info --
+{"Version":"v1.0.0","Time":"2018-10-22T18:45:39Z"}
+
+-- go.mod --
+module fruit.com
+
+-- fruit/fruit.go --
+package main
+
+const Name = "Orange"

goproxytest/testdata/mod/fruit.com_v1.1.0/.info

@@ -0,0 +1 @@
+{"Version":"v1.1.0","Time":"2018-10-22T18:45:39Z"}

goproxytest/testdata/mod/fruit.com_v1.1.0/.mod

@@ -0,0 +1 @@
+module fruit.com

goproxytest/testdata/mod/fruit.com_v1.1.0/fruit/main.go

@@ -0,0 +1,3 @@
+package fruit
+
+const Name = "Apple"