Merge pull request #3 from hhuang-rayark/feature/export_auther

Allow customized auther in Transport

auther.go

@@ -36,27 +36,28 @@ type clock interface {
 	Now() time.Time
 }
 
-// auther adds an "OAuth" Authorization header field to requests.
-type auther struct {
+// DefaultAuther adds an "OAuth" Authorization header field to requests.
+type DefaultAuther struct {
 	config *Config
 	clock  clock
 }
 
-func newAuther(config *Config) *auther {
+// NewDefaultAuther returns a new DefaultAuther
+func NewDefaultAuther(config *Config) *DefaultAuther {
 	if config == nil {
 		config = &Config{}
 	}
 	if config.Noncer == nil {
 		config.Noncer = Base64Noncer{}
 	}
-	return &auther{
+	return &DefaultAuther{
 		config: config,
 	}
 }
 
 // setRequestTokenAuthHeader adds the OAuth1 header for the request token
 // request (temporary credential) according to RFC 5849 2.1.
-func (a *auther) setRequestTokenAuthHeader(req *http.Request) error {
+func (a *DefaultAuther) setRequestTokenAuthHeader(req *http.Request) error {
 	oauthParams := a.commonOAuthParams()
 	oauthParams[oauthCallbackParam] = a.config.CallbackURL
 	params, err := collectParameters(req, oauthParams)
@@ -78,7 +79,7 @@ func (a *auther) setRequestTokenAuthHeader(req *http.Request) error {
 
 // setAccessTokenAuthHeader sets the OAuth1 header for the access token request
 // (token credential) according to RFC 5849 2.3.
-func (a *auther) setAccessTokenAuthHeader(req *http.Request, requestToken, requestSecret, verifier string) error {
+func (a *DefaultAuther) setAccessTokenAuthHeader(req *http.Request, requestToken, requestSecret, verifier string) error {
 	oauthParams := a.commonOAuthParams()
 	oauthParams[oauthTokenParam] = requestToken
 	oauthParams[oauthVerifierParam] = verifier
@@ -96,9 +97,9 @@ func (a *auther) setAccessTokenAuthHeader(req *http.Request, requestToken, reque
 	return nil
 }
 
-// setRequestAuthHeader sets the OAuth1 header for making authenticated
+// SetRequestAuthHeader sets the OAuth1 header for making authenticated
 // requests with an AccessToken (token credential) according to RFC 5849 3.1.
-func (a *auther) setRequestAuthHeader(req *http.Request, accessToken *Token) error {
+func (a *DefaultAuther) SetRequestAuthHeader(req *http.Request, accessToken *Token) error {
 	oauthParams := a.commonOAuthParams()
 	oauthParams[oauthTokenParam] = accessToken.Token
 	params, err := collectParameters(req, oauthParams)
@@ -119,7 +120,7 @@ func (a *auther) setRequestAuthHeader(req *http.Request, accessToken *Token) err
 // excluding the oauth_signature parameter. This includes the realm parameter
 // if it was set in the config. The realm parameter will not be included in
 // the signature base string as specified in RFC 5849 3.4.1.3.1.
-func (a *auther) commonOAuthParams() map[string]string {
+func (a *DefaultAuther) commonOAuthParams() map[string]string {
 	params := map[string]string{
 		oauthConsumerKeyParam:     a.config.ConsumerKey,
 		oauthSignatureMethodParam: a.signer().Name(),
@@ -134,20 +135,20 @@ func (a *auther) commonOAuthParams() map[string]string {
 }
 
 // Returns a nonce using the configured Noncer.
-func (a *auther) nonce() string {
+func (a *DefaultAuther) nonce() string {
 	return a.config.Noncer.Nonce()
 }
 
 // Returns the Unix epoch seconds.
-func (a *auther) epoch() int64 {
+func (a *DefaultAuther) epoch() int64 {
 	if a.clock != nil {
 		return a.clock.Now().Unix()
 	}
 	return time.Now().Unix()
 }
 
 // Returns the Config's Signer or the default Signer.
-func (a *auther) signer() Signer {
+func (a *DefaultAuther) signer() Signer {
 	if a.config.Signer != nil {
 		return a.config.Signer
 	}

auther_test.go

@@ -12,11 +12,11 @@ import (
 
 func TestCommonOAuthParams(t *testing.T) {
 	cases := []struct {
-		auther         *auther
+		DefaultAuther  *DefaultAuther
 		expectedParams map[string]string
 	}{
 		{
-			&auther{
+			&DefaultAuther{
 				&Config{
 					ConsumerKey: "some_consumer_key",
 					Noncer:      &fixedNoncer{"some_nonce"},
@@ -32,7 +32,7 @@ func TestCommonOAuthParams(t *testing.T) {
 			},
 		},
 		{
-			&auther{
+			&DefaultAuther{
 				&Config{
 					ConsumerKey: "some_consumer_key",
 					Realm:       "photos",
@@ -52,13 +52,13 @@ func TestCommonOAuthParams(t *testing.T) {
 	}
 
 	for _, c := range cases {
-		assert.Equal(t, c.expectedParams, c.auther.commonOAuthParams())
+		assert.Equal(t, c.expectedParams, c.DefaultAuther.commonOAuthParams())
 	}
 }
 
 func TestNonce(t *testing.T) {
-	auther := newAuther(nil)
-	nonce := auther.nonce()
+	DefaultAuther := NewDefaultAuther(nil)
+	nonce := DefaultAuther.nonce()
 	// assert that 32 bytes (256 bites) become 44 bytes since a base64 byte
 	// zeros the 2 high bits. 3 bytes convert to 4 base64 bytes, 40 base64 bytes
 	// represent the first 30 of 32 bytes, = padding adds another 4 byte group.
@@ -67,17 +67,17 @@ func TestNonce(t *testing.T) {
 }
 
 func TestEpoch(t *testing.T) {
-	a := newAuther(nil)
+	a := NewDefaultAuther(nil)
 	// assert that a real time is used by default
 	assert.InEpsilon(t, time.Now().Unix(), a.epoch(), 1)
 	// assert that the fixed clock can be used for testing
-	a = &auther{clock: &fixedClock{time.Unix(50037133, 0)}}
+	a = &DefaultAuther{clock: &fixedClock{time.Unix(50037133, 0)}}
 	assert.Equal(t, int64(50037133), a.epoch())
 }
 
 func TestSigner_Default(t *testing.T) {
 	config := &Config{ConsumerSecret: "consumer_secret"}
-	a := newAuther(config)
+	a := NewDefaultAuther(config)
 	// echo -n "hello world" | openssl dgst -sha1 -hmac "consumer_secret&token_secret" -binary | base64
 	expectedSignature := "BE0uILOruKfSXd4UzYlLJDfOq08="
 	// assert that the default signer produces the expected HMAC-SHA1 digest
@@ -92,7 +92,7 @@ func TestSigner_SHA256(t *testing.T) {
 	config := &Config{
 		Signer: &HMAC256Signer{ConsumerSecret: "consumer_secret"},
 	}
-	a := newAuther(config)
+	a := NewDefaultAuther(config)
 	// echo -n "hello world" | openssl dgst -sha256 -hmac "consumer_secret&token_secret" -binary | base64
 	expectedSignature := "pW9drXUyErU8DASWbsP2I3XZbju37AW+VzcGdYSeMo8="
 	// assert that the signer produces the expected HMAC-SHA256 digest
@@ -118,7 +118,7 @@ func TestSigner_Custom(t *testing.T) {
 		ConsumerSecret: "consumer_secret",
 		Signer:         &identitySigner{},
 	}
-	a := newAuther(config)
+	a := NewDefaultAuther(config)
 	// assert that the custom signer is used
 	method := a.signer().Name()
 	digest, err := a.signer().Sign("secret", "hello world")

config.go

@@ -50,11 +50,7 @@ func (c *Config) Client(ctx context.Context, t *Token) *http.Client {
 
 // NewClient returns a new http Client which signs requests via OAuth1.
 func NewClient(ctx context.Context, config *Config, token *Token) *http.Client {
-	transport := &Transport{
-		Base:   contextTransport(ctx),
-		source: StaticTokenSource(token),
-		auther: newAuther(config),
-	}
+	transport := newTransport(contextTransport(ctx), StaticTokenSource(token), NewDefaultAuther(config))
 	return &http.Client{Transport: transport}
 }
 
@@ -69,7 +65,7 @@ func (c *Config) RequestToken() (requestToken, requestSecret string, err error)
 	if err != nil {
 		return "", "", err
 	}
-	err = newAuther(c).setRequestTokenAuthHeader(req)
+	err = NewDefaultAuther(c).setRequestTokenAuthHeader(req)
 	if err != nil {
 		return "", "", err
 	}
@@ -148,7 +144,7 @@ func (c *Config) AccessToken(requestToken, requestSecret, verifier string) (acce
 	if err != nil {
 		return "", "", err
 	}
-	err = newAuther(c).setAccessTokenAuthHeader(req, requestToken, requestSecret, verifier)
+	err = NewDefaultAuther(c).setAccessTokenAuthHeader(req, requestToken, requestSecret, verifier)
 	if err != nil {
 		return "", "", err
 	}

reference_test.go

@@ -36,7 +36,7 @@ func TestTwitterRequestTokenAuthHeader(t *testing.T) {
 		Noncer: &fixedNoncer{expectedNonce},
 	}
 
-	auther := &auther{config, &fixedClock{time.Unix(unixTimestamp, 0)}}
+	auther := &DefaultAuther{config, &fixedClock{time.Unix(unixTimestamp, 0)}}
 	req, err := http.NewRequest("POST", config.Endpoint.RequestTokenURL, nil)
 	assert.Nil(t, err)
 	err = auther.setRequestTokenAuthHeader(req)
@@ -74,7 +74,7 @@ func TestTwitterAccessTokenAuthHeader(t *testing.T) {
 		Noncer: &fixedNoncer{expectedNonce},
 	}
 
-	auther := &auther{config, &fixedClock{time.Unix(unixTimestamp, 0)}}
+	auther := &DefaultAuther{config, &fixedClock{time.Unix(unixTimestamp, 0)}}
 	req, err := http.NewRequest("POST", config.Endpoint.AccessTokenURL, nil)
 	assert.Nil(t, err)
 	err = auther.setAccessTokenAuthHeader(req, expectedRequestToken, requestTokenSecret, expectedVerifier)
@@ -111,7 +111,7 @@ var twitterConfig = &Config{
 }
 
 func TestTwitterParameterString(t *testing.T) {
-	auther := &auther{twitterConfig, &fixedClock{time.Unix(unixTimestampOfRequest, 0)}}
+	auther := &DefaultAuther{twitterConfig, &fixedClock{time.Unix(unixTimestampOfRequest, 0)}}
 	values := url.Values{}
 	values.Add("status", "Hello Ladies + Gentlemen, a signed OAuth request!")
 	// note: the reference example is old and uses api v1 in the URL
@@ -128,7 +128,7 @@ func TestTwitterParameterString(t *testing.T) {
 }
 
 func TestTwitterSignatureBase(t *testing.T) {
-	auther := &auther{twitterConfig, &fixedClock{time.Unix(unixTimestampOfRequest, 0)}}
+	auther := &DefaultAuther{twitterConfig, &fixedClock{time.Unix(unixTimestampOfRequest, 0)}}
 	values := url.Values{}
 	values.Add("status", "Hello Ladies + Gentlemen, a signed OAuth request!")
 	// note: the reference example is old and uses api v1 in the URL
@@ -151,15 +151,15 @@ func TestTwitterRequestAuthHeader(t *testing.T) {
 	expectedSignature := PercentEncode("tnnArxj06cWHq44gCs1OSKk/jLY=")
 	expectedTimestamp := "1318622958"
 
-	auther := &auther{twitterConfig, &fixedClock{time.Unix(unixTimestampOfRequest, 0)}}
+	auther := &DefaultAuther{twitterConfig, &fixedClock{time.Unix(unixTimestampOfRequest, 0)}}
 	values := url.Values{}
 	values.Add("status", "Hello Ladies + Gentlemen, a signed OAuth request!")
 
 	accessToken := &Token{expectedTwitterOAuthToken, oauthTokenSecret}
 	req, err := http.NewRequest("POST", "https://api.twitter.com/1/statuses/update.json?include_entities=true", strings.NewReader(values.Encode()))
 	assert.Nil(t, err)
 	req.Header.Set(contentType, formContentType)
-	err = auther.setRequestAuthHeader(req, accessToken)
+	err = auther.SetRequestAuthHeader(req, accessToken)
 	// assert that request is signed and has an access token token
 	assert.Nil(t, err)
 	params := parseOAuthParamsOrFail(t, req.Header.Get(authorizationHeaderParam))

transport.go

@@ -5,6 +5,10 @@ import (
 	"net/http"
 )
 
+type Auther interface {
+	SetRequestAuthHeader(req *http.Request, accessToken *Token) error
+}
+
 // Transport is an http.RoundTripper which makes OAuth1 HTTP requests. It
 // wraps a base RoundTripper and adds an Authorization header using the
 // token from a TokenSource.
@@ -18,25 +22,43 @@ type Transport struct {
 	// source supplies the token to use when signing a request
 	source TokenSource
 	// auther adds OAuth1 Authorization headers to requests
-	auther *auther
+	auther Auther
+}
+
+// NewTransport returns a new Transport and an error
+func NewTransport(baseRoundTripper http.RoundTripper, source TokenSource, auther Auther) (*Transport, error) {
+	t := newTransport(baseRoundTripper, source, auther)
+	err := t.checkValid()
+	if err != nil {
+		return nil, err
+	}
+	return t, nil
+}
+
+// newTransport returns a new Transport without checking whether there is an error
+// newTransport is only for NewTransport & NewClient
+func newTransport(baseRoundTripper http.RoundTripper, source TokenSource, auther Auther) *Transport {
+	return &Transport{
+		Base:   baseRoundTripper,
+		source: source,
+		auther: auther,
+	}
 }
 
 // RoundTrip authorizes the request with a signed OAuth1 Authorization header
 // using the auther and TokenSource.
 func (t *Transport) RoundTrip(req *http.Request) (*http.Response, error) {
-	if t.source == nil {
-		return nil, fmt.Errorf("oauth1: Transport's source is nil")
+	err := t.checkValid()
+	if err != nil {
+		return nil, err
 	}
 	accessToken, err := t.source.Token()
 	if err != nil {
 		return nil, err
 	}
-	if t.auther == nil {
-		return nil, fmt.Errorf("oauth1: Transport's auther is nil")
-	}
 	// RoundTripper should not modify the given request, clone it
 	req2 := cloneRequest(req)
-	err = t.auther.setRequestAuthHeader(req2, accessToken)
+	err = t.auther.SetRequestAuthHeader(req2, accessToken)
 	if err != nil {
 		return nil, err
 	}
@@ -63,3 +85,17 @@ func cloneRequest(req *http.Request) *http.Request {
 	}
 	return r2
 }
+
+func (t *Transport) checkValid() error {
+	if t.source == nil {
+		return fmt.Errorf("oauth1: Transport's source is nil")
+	}
+	if t.auther == nil {
+		return fmt.Errorf("oauth1: Transport's auther is nil")
+	}
+	_, err := t.source.Token()
+	if err != nil {
+		return err
+	}
+	return nil
+}