From 4d489f16868093dea5fcf5c61ceb76b13caae351 Mon Sep 17 00:00:00 2001
From: surdeus <surdeus@gmail.com>
Date: Sat, 27 Jan 2024 09:21:02 +0300
Subject: [PATCH] feat: autorefreshing after the access token expires.

---
 api/api.go | 33 ++++++++++++++++++++++++++++++++-
 1 file changed, 32 insertions(+), 1 deletion(-)

diff --git a/api/api.go b/api/api.go
index 1dcad28..e521b4d 100644
--- a/api/api.go
+++ b/api/api.go
@@ -29,7 +29,7 @@ type ClientOptions struct {
 	ClientSecret string `json:"client_secret"`
 
 	AccessToken  string `json:"access_token"`
-	ExpirationDate time.Time `json:"access"`
+	ExpirationAt time.Time `json:"expiration_at"`
 	RefreshToken string `json:"refresh_token"`
 }
 
@@ -265,6 +265,10 @@ func (api *Client) ExchangeAuth() (*TokenPair, error) {
 
 	api.options.AccessToken = result.AccessToken
 	api.options.RefreshToken = result.RefreshToken
+	now := time.Now()
+	api.options.ExpirationAt = now.Add(
+		time.Second*time.Duration(result.ExpiresIn),
+	)
 	err = api.writeSecret()
 	if err != nil {
 		return nil, err
@@ -272,6 +276,17 @@ func (api *Client) ExchangeAuth() (*TokenPair, error) {
 	return ret, nil
 }
 
+func (api *Client) RefreshTokenIfExpired() error {
+	now := time.Now()
+	if now.After(api.options.ExpirationAt.Add(-time.Second*2)) {
+		_, err := api.RefreshToken()
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 func (api *Client) RefreshToken() (*OauthTokenResponse, error) {
 	result := new(OauthTokenResponse)
 	request := map[string]string{
@@ -293,6 +308,10 @@ func (api *Client) RefreshToken() (*OauthTokenResponse, error) {
 
 	api.options.AccessToken = result.AccessToken
 	api.options.RefreshToken = result.RefreshToken
+	now := time.Now()
+	api.options.ExpirationAt = now.Add(
+		time.Second*time.Duration(result.ExpiresIn),
+	)
 	err = api.writeSecret()
 	if err != nil {
 		return nil, err
@@ -306,6 +325,10 @@ func (api *Client) Get(resource string, result interface{}, abs ...bool) error {
 	if len(abs) > 0 {
 		a = abs[0]
 	} 
+	err := api.RefreshTokenIfExpired()
+	if err != nil {
+		return err
+	}
 	return api.doRequest(resource, requestOptions{
 		HttpMethod: http.MethodGet,
 		Body:       nil,
@@ -315,6 +338,10 @@ func (api *Client) Get(resource string, result interface{}, abs ...bool) error {
 }
 
 func (api *Client) Post(resource string, request interface{}, result interface{}) error {
+	err := api.RefreshTokenIfExpired()
+	if err != nil {
+		return err
+	}
 	return api.doRequest(resource, requestOptions{
 		HttpMethod: http.MethodPost,
 		Body:       request,
@@ -323,6 +350,10 @@ func (api *Client) Post(resource string, request interface{}, result interface{}
 }
 
 func (api *Client) Patch(resource string, request interface{}, result interface{}) error {
+	err := api.RefreshTokenIfExpired()
+	if err != nil {
+		return err
+	}
 	return api.doRequest(resource, requestOptions{
 		HttpMethod: http.MethodPatch,
 		Body:       request,