all: use OAuth2 refresh token in storage config

cloud/storage/dropbox/dropbox.go

@@ -14,27 +14,22 @@ import (
 	"net/http"
 	"strings"
 
+	"dropbox.upspin.io/oauth2"
 	"upspin.io/cloud/storage"
 	"upspin.io/errors"
 	"upspin.io/upspin"
 )
 
-// apiToken is the key for the dial options in the storage.Storage interface.
-const apiToken = "token"
-
 // New initializes a Storage implementation that stores data to Dropbox.
 func New(opts *storage.Opts) (storage.Storage, error) {
 	const op errors.Op = "cloud/storage/dropbox.New"
 
-	tok, ok := opts.Opts[apiToken]
+	token, ok := opts.Opts["refresh_token"]
 	if !ok {
-		return nil, errors.E(op, errors.Invalid, errors.Errorf("%q option is required", apiToken))
+		return nil, errors.E(op, errors.Invalid, errors.Errorf("refresh_token option is required"))
 	}
 
-	return &dropboxImpl{
-		client: http.DefaultClient,
-		token:  tok,
-	}, nil
+	return &dropboxImpl{oauth2.Client(token)}, nil
 }
 
 func init() {
@@ -44,7 +39,6 @@ func init() {
 // dropboxImpl is an implementation of Storage that connects to a Dropbox backend.
 type dropboxImpl struct {
 	client *http.Client
-	token  string
 }
 
 var (
@@ -216,7 +210,6 @@ func (d *dropboxImpl) newRequest(path string, body io.Reader, arg string) (*http
 		return nil, err
 	}
 
-	req.Header.Add("Authorization", "Bearer "+d.token)
 	req.Header.Add("Content-Type", "application/octet-stream")
 
 	if arg != "" {

cloud/storage/dropbox/dropbox_test.go

@@ -16,6 +16,7 @@ import (
 
 	"golang.org/x/oauth2"
 
+	dboauth2 "dropbox.upspin.io/oauth2"
 	"upspin.io/cloud/storage"
 	"upspin.io/upspin"
 )
@@ -30,6 +31,17 @@ var (
 	useDropbox = flag.Bool("use_dropbox", false, "enable to run dropbox tests; requires authentication code")
 )
 
+func init() {
+	dboauth2.Config = &oauth2.Config{
+		ClientID:     "ufhy41x7g4obzqz",
+		ClientSecret: "vuhgmucmxm93dp5",
+		Endpoint: oauth2.Endpoint{
+			AuthURL:  "https://www.dropbox.com/oauth2/authorize",
+			TokenURL: "https://api.dropboxapi.com/oauth2/token",
+		},
+	}
+}
+
 func TestList(t *testing.T) {
 	ls, ok := client.(storage.Lister)
 	if !ok {
@@ -139,7 +151,7 @@ func TestMain(m *testing.M) {
 cloud/storage/dropbox: skipping test as it requires Dropbox access. To enable this test,
 on the first run get an authentication code by visiting:
 
-https://www.dropbox.com/oauth2/authorize?client_id=ufhy41x7g4obzqz&response_type=code
+https://www.dropbox.com/oauth2/authorize?client_id=ufhy41x7g4obzqz&response_type=code&token_access_type=offline
 
 Copy the code and pass it by the -code flag. This will get an oAuth2 access token, store
 it and reuse it in successive test calls.
@@ -155,7 +167,7 @@ it and reuse it in successive test calls.
 
 	// Create client that writes to your Dropbox.
 	client, err = storage.Dial("Dropbox",
-		storage.WithKeyValue("token", t))
+		storage.WithKeyValue("refresh_token", t))
 	if err != nil {
 		log.Fatalf("cloud/storage/dropbox: couldn't set up client: %v", err)
 	}
@@ -173,23 +185,14 @@ func token() (string, error) {
 		return string(token), nil
 	}
 
-	conf := &oauth2.Config{
-		ClientID:     "ufhy41x7g4obzqz",
-		ClientSecret: "vuhgmucmxm93dp5",
-		Endpoint: oauth2.Endpoint{
-			AuthURL:  "https://www.dropbox.com/oauth2/authorize",
-			TokenURL: "https://api.dropboxapi.com/oauth2/token",
-		},
-	}
-
-	tok, err := conf.Exchange(oauth2.NoContext, *authCode)
+	tok, err := dboauth2.Exchange(*authCode)
 	if err != nil {
 		return "", err
 	}
 
-	if err := ioutil.WriteFile(tokenFile, []byte(tok.AccessToken), 0600); err != nil {
+	if err := ioutil.WriteFile(tokenFile, []byte(tok), 0600); err != nil {
 		return "", err
 	}
 
-	return tok.AccessToken, nil
+	return tok, nil
 }

cmd/upspin-setupstorage-dropbox/setupstorage.go

@@ -14,8 +14,7 @@ import (
 	"os"
 	"path/filepath"
 
-	"golang.org/x/oauth2"
-
+	"dropbox.upspin.io/oauth2"
 	"upspin.io/subcmd"
 )
 
@@ -33,7 +32,7 @@ the specified authorization code to access your Dropbox.
 
 Before running this command, you must obtain an authorization code:
 
-1. Go to https://www.dropbox.com/oauth2/authorize?client_id=wt1281n3q768jj3&response_type=code
+1. Go to https://www.dropbox.com/oauth2/authorize?client_id=wt1281n3q768jj3&response_type=code&token_access_type=offline
 2. Click "Allow" (you might have to log in first).
 3. Copy the authorization code
 4. Run setupstorage-dropbox -domain <domain.tld> <authorization_code>
@@ -65,32 +64,18 @@ func main() {
 
 	cfgPath := filepath.Join(*where, *domain)
 	cfg := s.ReadServerConfig(cfgPath)
+	token, err := oauth2.Exchange(authCode)
+	if err != nil {
+		s.Exit(err)
+	}
 
 	cfg.StoreConfig = []string{
 		"backend=Dropbox",
-		"token=" + s.token(authCode),
+		"refresh_token=" + token,
 	}
 	s.WriteServerConfig(cfgPath, cfg)
 
 	fmt.Fprintf(os.Stderr, "You should now deploy the upspinserver binary and run 'upspin setupserver'.\n")
 
 	s.ExitNow()
 }
-
-func (s *state) token(code string) string {
-	conf := &oauth2.Config{
-		ClientID:     "wt1281n3q768jj3",
-		ClientSecret: "blk944sx4oyf6aq",
-		Endpoint: oauth2.Endpoint{
-			AuthURL:  "https://www.dropbox.com/oauth2/authorize",
-			TokenURL: "https://api.dropboxapi.com/oauth2/token",
-		},
-	}
-
-	token, err := conf.Exchange(oauth2.NoContext, code)
-	if err != nil {
-		s.Exit(err)
-	}
-
-	return token.AccessToken
-}

oauth2/config.go

@@ -0,0 +1,40 @@
+// Copyright 2017 The Upspin 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 oauth2
+
+import (
+	"context"
+	"net/http"
+
+	"golang.org/x/oauth2"
+)
+
+// The default Dropbox client configuration; this client uses the `Apps/upspin/`
+// folder in the linked Dropbox account for storage.
+var Config = &oauth2.Config{
+	ClientID:     "wt1281n3q768jj3",
+	ClientSecret: "blk944sx4oyf6aq",
+	Endpoint: oauth2.Endpoint{
+		AuthURL:  "https://www.dropbox.com/oauth2/authorize",
+		TokenURL: "https://api.dropboxapi.com/oauth2/token",
+	},
+}
+
+// Client returns an HTTP client that populates the Authorization header of all
+// requests with an access token.
+func Client(refreshToken string) *http.Client {
+	token := oauth2.Token{RefreshToken: refreshToken}
+	return Config.Client(context.Background(), &token)
+}
+
+// Exchange converts the authorization code into a refresh token.
+func Exchange(authCode string) (string, error) {
+	token, err := Config.Exchange(context.Background(), authCode)
+	if err != nil {
+		return "", err
+	}
+
+	return token.RefreshToken, nil
+}