Detect when the token is refreshed

- Move all OAuth2 related code to oauth2 subpackage. - Duplicate part of the golang.org/x/oauth2/internal package for implementing a custom TokenSource that calls a custom handler on token change/refresh. - Only provide the TokenSource instead of the oauth2.Config to the Client.
printesoi · Apr 9, 2024 · 1781233 · 1781233
1 parent c07f4d4
commit 1781233
Show file tree

Hide file tree

Showing 14 changed files with 954 additions and 237 deletions.
diff --git a/README.md b/README.md
@@ -42,15 +42,18 @@ This package can be use both for interacting with (calling) the ANAF e-factura
 API via the Client object and for generating an Invoice UBL XML.
 
 ```go
-import "github.com/printesoi/e-factura-go"
+import (
+    "github.com/printesoi/e-factura-go"
+    efactura_oauth2 "github.com/printesoi/e-factura-go/oauth2"
+)
 ```
 
 Construct the required OAuth2 config needed for the Client:
 
 ```go
-oauth2Cfg, err := efactura.MakeOAuth2Config(
-    efactura.OAuth2ConfigCredentials(anafAppClientID, anafApplientSecret),
-    efactura.OAuth2ConfigRedirectURL(anafAppRedirectURL),
+oauth2Cfg, err := efactura_oauth2.MakeConfig(
+    efactura_oauth2.ConfigCredentials(anafAppClientID, anafApplientSecret),
+    efactura_oauth2.ConfigRedirectURL(anafAppRedirectURL),
 )
 if err != nil {
     // Handle error
@@ -69,7 +72,7 @@ to the redirect URL):
 
 ```go
 // Assuming the oauth2Cfg is built as above
-initialToken, err := oauth2Cfg.Exchange(ctx, authorizationCode)
+token, err := oauth2Cfg.Exchange(ctx, authorizationCode)
 if err != nil {
     // Handle error
 }
@@ -81,7 +84,7 @@ will also receive the `state` parameter with `code`.
 Parse the initial token from JSON:
 
 ```go
-initialToken, err := efactura.TokenFromJSON([]byte(tokenJSON))
+token, err := efactura.TokenFromJSON([]byte(tokenJSON))
 if err != nil {
     // Handle error
 }
@@ -93,7 +96,26 @@ Construct a new client:
 client, err := efactura.NewClient(
     context.Background(),
     efactura.ClientOAuth2Config(oauth2Cfg),
-    efactura.ClientOAuth2InitialToken(initialToken),
+    efactura.ClientOAuth2TokenSource(efactura_oauth2.TokenSource(token)),
+    efactura.ClientProductionEnvironment(false), // false for test, true for production mode
+)
+if err != nil {
+    // Handle error
+}
+```
+
+If you want to store the token in a store/db and update it everytime it
+refreshes use `efactura_oauth2.TokenSourceWithChangedHandler`:
+
+```go
+onTokenChanged := func(ctx context.Context, token *xoauth.Token) error {
+    fmt.Printf("Token changed...")
+    return nil
+}
+client, err := efactura.NewClient(
+    context.Background(),
+    efactura.ClientOAuth2Config(oauth2Cfg),
+    efactura.ClientOAuth2TokenSource(efactura_oauth2.TokenSourceWithChangedHandler(token, onTokenChanged)),
     efactura.ClientProductionEnvironment(false), // false for test, true for production mode
 )
 if err != nil {
@@ -311,11 +333,6 @@ cannot unmarshal a struct like efactura.Invoice due to namespace prefixes!
   XML (maybe checking with the tools provided by mfinante).
 - [ ] Godoc and more code examples.
 - [ ] Test coverage
-- [ ] Support full OAuth2 authentication flow for the client, not just passing
-  the initial token. This however will be tricky to implement properly since
-  the OAuth2 app registered in the ANAF developer profile must have a fixed
-  list of HTTPS redirect URLs and the redirect URL used for creating the OAuth2
-  config must exactly matche one of the URLs.
 
 ## Contributing ##
 

diff --git a/client.go b/client.go
@@ -23,12 +23,7 @@ import (
 	"net/url"
 	"strings"
 
-	"golang.org/x/oauth2"
-)
-
-var (
-	ErrInvalidClientOAuth2Config = errors.New("Invalid OAuth2Config provided")
-	ErrInvalidClientOAuth2Token  = errors.New("Invalid Auth token provided")
+	xoauth2 "golang.org/x/oauth2"
 )
 
 const (
@@ -68,10 +63,8 @@ type Client struct {
 	apiPublicBaseURL *url.URL
 	userAgent        string
 
-	oauth2Cfg    OAuth2Config
-	initialToken *oauth2.Token
-
-	apiClient *http.Client
+	tokenSource xoauth2.TokenSource
+	apiClient   *http.Client
 }
 
 // NewClient creates a new client using the provided config options.
@@ -93,18 +86,14 @@ func NewClient(ctx context.Context, opts ...ClientConfigOption) (*Client, error)
 		apiPublicBaseURL = apiPublicBaseProd
 	}
 
-	if !cfg.OAuth2Config.Valid() {
-		return nil, ErrInvalidClientOAuth2Config
-	}
-	if !cfg.InitialToken.Valid() {
-		return nil, ErrInvalidClientOAuth2Token
+	if cfg.TokenSource == nil {
+		return nil, errors.New("invalid token source for client")
 	}
 
 	client := new(Client)
 	client.userAgent = defaultUserAgent
-	client.oauth2Cfg = cfg.OAuth2Config
-	client.initialToken = cfg.InitialToken
-	client.apiClient = cfg.OAuth2Config.Client(ctx, cfg.InitialToken)
+	client.tokenSource = cfg.TokenSource
+	client.apiClient = xoauth2.NewClient(ctx, client.tokenSource)
 	if cfg.UserAgent != nil {
 		client.userAgent = *cfg.UserAgent
 	}

diff --git a/client_test.go b/client_test.go
@@ -25,8 +25,9 @@ import (
 	"testing"
 	"time"
 
+	"github.com/printesoi/e-factura-go/oauth2"
 	"github.com/stretchr/testify/assert"
-	"golang.org/x/oauth2"
+	xoauth2 "golang.org/x/oauth2"
 )
 
 // setupTestEnvOAuth2Config creates a OAuth2Config from the environment.
@@ -35,7 +36,7 @@ import (
 // EFACTURA_TEST_REDIRECT_URL are not set, this method returns an error.
 // If skipIfEmptyEnv is set to true and the env vars
 // are not set, this method returns a nil config.
-func setupTestEnvOAuth2Config(skipIfEmptyEnv bool) (oauth2Cfg *OAuth2Config, err error) {
+func setupTestEnvOAuth2Config(skipIfEmptyEnv bool) (oauth2Cfg *oauth2.Config, err error) {
 	clientID := os.Getenv("EFACTURA_TEST_CLIENT_ID")
 	clientSecret := os.Getenv("EFACTURA_TEST_CLIENT_SECRET")
 	if clientID == "" || clientSecret == "" {
@@ -52,9 +53,9 @@ func setupTestEnvOAuth2Config(skipIfEmptyEnv bool) (oauth2Cfg *OAuth2Config, err
 		return
 	}
 
-	if cfg, er := MakeOAuth2Config(
-		OAuth2ConfigCredentials(clientID, clientSecret),
-		OAuth2ConfigRedirectURL(redirectURL),
+	if cfg, er := oauth2.MakeConfig(
+		oauth2.ConfigCredentials(clientID, clientSecret),
+		oauth2.ConfigRedirectURL(redirectURL),
 	); er != nil {
 		err = er
 		return
@@ -64,9 +65,13 @@ func setupTestEnvOAuth2Config(skipIfEmptyEnv bool) (oauth2Cfg *OAuth2Config, err
 	return
 }
 
+func getTestCIF() string {
+	return os.Getenv("EFACTURA_TEST_CIF")
+}
+
 // setupRealClient creates a real sandboxed Client (a client that talks to the
 // ANAF TEST APIs).
-func setupRealClient(skipIfEmptyEnv bool, oauth2Cfg *OAuth2Config) (*Client, error) {
+func setupRealClient(skipIfEmptyEnv bool, oauth2Cfg *oauth2.Config) (*Client, error) {
 	if oauth2Cfg == nil {
 		cfg, err := setupTestEnvOAuth2Config(skipIfEmptyEnv)
 		if err != nil {
@@ -83,23 +88,33 @@ func setupRealClient(skipIfEmptyEnv bool, oauth2Cfg *OAuth2Config) (*Client, err
 		return nil, errors.New("Invalid initial token json")
 	}
 
-	token, err := TokenFromJSON([]byte(tokenJSON))
+	token, err := oauth2.TokenFromJSON([]byte(tokenJSON))
 	if err != nil {
 		return nil, err
 	}
 
-	client, err := NewClient(
-		context.Background(),
-		ClientOAuth2Config(*oauth2Cfg),
-		ClientOAuth2InitialToken(token),
-		ClientSandboxEnvironment(true),
+	sandbox := true
+	if os.Getenv("EFACTURA_TEST_PRODUCTION") == getTestCIF() {
+		sandbox = false
+	}
+
+	onTokenChanged := func(ctx context.Context, token *xoauth2.Token) error {
+		tokenJSON, _ := json.Marshal(token)
+		fmt.Printf("[E-FACTURA] token changed: %s\n", string(tokenJSON))
+		return nil
+	}
+
+	ctx := context.Background()
+	client, err := NewClient(ctx,
+		ClientOAuth2TokenSource(oauth2Cfg.TokenSourceWithChangedHandler(ctx, token, onTokenChanged)),
+		ClientSandboxEnvironment(sandbox),
 	)
 	return client, err
 }
 
 // setupTestOAuth2Config sets up a test HTTP server along with a OAuth2Config
 // that is configured to talk to that test server.
-func setupTestOAuth2Config(clientID, clientSecret string) (oauth2Cfg OAuth2Config, mux *http.ServeMux, serverURL string, teardown func(), err error) {
+func setupTestOAuth2Config(clientID, clientSecret string) (oauth2Cfg oauth2.Config, mux *http.ServeMux, serverURL string, teardown func(), err error) {
 	// mux is the HTTP request multiplexer used with the test server.
 	mux = http.NewServeMux()
 
@@ -119,13 +134,13 @@ func setupTestOAuth2Config(clientID, clientSecret string) (oauth2Cfg OAuth2Confi
 	if err != nil {
 		return
 	}
-	oauth2Cfg, err = MakeOAuth2Config(
-		OAuth2ConfigCredentials(clientID, clientSecret),
-		OAuth2ConfigRedirectURL(redirectURL),
-		OAuth2ConfigEndpoint(oauth2.Endpoint{
+	oauth2Cfg, err = oauth2.MakeConfig(
+		oauth2.ConfigCredentials(clientID, clientSecret),
+		oauth2.ConfigRedirectURL(redirectURL),
+		oauth2.ConfigEndpoint(xoauth2.Endpoint{
 			AuthURL:   authorizeURL,
 			TokenURL:  tokenURL,
-			AuthStyle: oauth2.AuthStyleInHeader,
+			AuthStyle: xoauth2.AuthStyleInHeader,
 		}),
 	)
 	if err != nil {
@@ -141,7 +156,7 @@ func setupTestOAuth2Config(clientID, clientSecret string) (oauth2Cfg OAuth2Confi
 // setupTestClient sets up a test HTTP server along with a Client that is
 // configured to talk to that test server. Tests should register handlers on
 // mux which provide mock responses for the API method being tested.
-func setupTestClient(oauth2Cfg OAuth2Config, initialToken *oauth2.Token) (client *Client, mux *http.ServeMux, serverURL string, teardown func(), err error) {
+func setupTestClient(token *xoauth2.Token) (client *Client, mux *http.ServeMux, serverURL string, teardown func(), err error) {
 	// mux is the HTTP request multiplexer used with the test server.
 	mux = http.NewServeMux()
 
@@ -157,8 +172,7 @@ func setupTestClient(oauth2Cfg OAuth2Config, initialToken *oauth2.Token) (client
 	serverURL = server.URL
 	client, err = NewClient(
 		context.Background(),
-		ClientOAuth2Config(oauth2Cfg),
-		ClientOAuth2InitialToken(initialToken),
+		ClientOAuth2TokenSource(xoauth2.StaticTokenSource(token)),
 		ClientSandboxEnvironment(true),
 		ClientBaseURL(serverURL+apiBasePathSandbox),
 		ClientBasePublicURL(serverURL+apiPublicBasePathProd),
@@ -261,7 +275,7 @@ func TestClientAuth(t *testing.T) {
 		return
 	}
 
-	client, clientMux, serverURL, clientTeardown, err := setupTestClient(oauth2Cfg, token)
+	client, clientMux, serverURL, clientTeardown, err := setupTestClient(token)
 	if clientTeardown != nil {
 		defer clientTeardown()
 	}

diff --git a/config.go b/config.go
@@ -15,18 +15,15 @@
 package efactura
 
 import (
-	"golang.org/x/oauth2"
+	xoauth2 "golang.org/x/oauth2"
 )
 
 // ClientConfig is the config used to create a Client
 type ClientConfig struct {
-	// OAuth2Config is the OAuth2 config used for creating the http.Client that
-	// autorefreshes the Token.
-	OAuth2Config OAuth2Config
-	// Token is the starting oauth2 Token (including the refresh token).
+	// TokenSource is the token source used for generating OAuth2 tokens.
 	// Until this library will support authentication with the SPV certificate,
 	// this must always be provided.
-	InitialToken *oauth2.Token
+	TokenSource xoauth2.TokenSource
 	// Unless BaseURL is set, Sandbox controlls whether to use production
 	// endpoints (if set to false) or test endpoints (if set to true).
 	Sandbox bool
@@ -47,17 +44,10 @@ type ClientConfig struct {
 // ClientConfigOption allows gradually modifying a ClientConfig
 type ClientConfigOption func(*ClientConfig)
 
-// ClientOAuth2Config sets the OAuth2 config
-func ClientOAuth2Config(oauth2Cfg OAuth2Config) ClientConfigOption {
+// ClientOAuth2TokenSource sets the token source to use.
+func ClientOAuth2TokenSource(tokenSource xoauth2.TokenSource) ClientConfigOption {
 	return func(c *ClientConfig) {
-		c.OAuth2Config = oauth2Cfg
-	}
-}
-
-// ClientOAuth2InitialToken sets the initial OAuth2 Token
-func ClientOAuth2InitialToken(token *oauth2.Token) ClientConfigOption {
-	return func(c *ClientConfig) {
-		c.InitialToken = token
+		c.TokenSource = tokenSource
 	}
 }