From 566f2a354cf452061e4b308966825b982549d76e Mon Sep 17 00:00:00 2001
From: Jeff Billimek <jeff@billimek.com>
Date: Thu, 9 Aug 2018 07:05:49 -0400
Subject: [PATCH] support for custom github endpoints (#115)

* support for custom github endpoints

* implementing requested changes

* refactor 'GitHubEndpointURL' to 'EndpointURL'
---
 config/example.yaml              |  1 +
 internal/handlers/auth.go        |  2 +-
 internal/handlers/auth/github.go | 13 +++++++++++--
 internal/util/config.go          |  1 +
 4 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/config/example.yaml b/config/example.yaml
index a2aeab6..afecb68 100644
--- a/config/example.yaml
+++ b/config/example.yaml
@@ -13,6 +13,7 @@ Google:  # only relevant when using the oauth authbackend
 GitHub:  # only relevant when using the oauth authbackend
   ClientID: replace me
   ClientSecret: replace me
+  EndpointURL: # (OPTIONAL) URL for custom endpoint (currently only for github); e.g. 'https://github.mydomain.com'
 Microsoft:  # only relevant when using the oauth authbackend
   ClientID: replace me
   ClientSecret: 'replace me'
diff --git a/internal/handlers/auth.go b/internal/handlers/auth.go
index 8c066e4..c7d7021 100644
--- a/internal/handlers/auth.go
+++ b/internal/handlers/auth.go
@@ -25,7 +25,7 @@ func (h *Handler) initOAuth() {
 	}
 	github := util.GetConfig().GitHub
 	if github.Enabled() {
-		auth.WithAdapterWrapper(auth.NewGithubAdapter(github.ClientID, github.ClientSecret), h.engine.Group("/api/v1/auth/github"))
+		auth.WithAdapterWrapper(auth.NewGithubAdapter(github.ClientID, github.ClientSecret, github.EndpointURL), h.engine.Group("/api/v1/auth/github"))
 		h.providers = append(h.providers, "github")
 	}
 	microsoft := util.GetConfig().Microsoft
diff --git a/internal/handlers/auth/github.go b/internal/handlers/auth/github.go
index 41eed81..574e84c 100644
--- a/internal/handlers/auth/github.go
+++ b/internal/handlers/auth/github.go
@@ -18,7 +18,11 @@ type githubAdapter struct {
 }
 
 // NewGithubAdapter creates an oAuth adapter out of the credentials and the baseURL
-func NewGithubAdapter(clientID, clientSecret string) Adapter {
+func NewGithubAdapter(clientID, clientSecret, endpointURL string) Adapter {
+	if endpointURL != "" {
+		github.Endpoint.AuthURL = endpointURL + "/login/oauth/authorize"
+		github.Endpoint.TokenURL = endpointURL + "/login/oauth/access_token"
+	}
 	return &githubAdapter{&oauth2.Config{
 		ClientID:     clientID,
 		ClientSecret: clientSecret,
@@ -40,7 +44,12 @@ func (a *githubAdapter) GetUserData(state, code string) (*user, error) {
 	if err != nil {
 		return nil, errors.Wrap(err, "could not exchange code")
 	}
-	oAuthUserInfoReq, err := a.config.Client(context.Background(), oAuthToken).Get("https://api.github.com/user")
+
+	gitHubUserURL := "https://api.github.com/user"
+	if util.GetConfig().GitHub.EndpointURL != "" {
+		gitHubUserURL = util.GetConfig().GitHub.EndpointURL + "/api/v3/user"
+	}
+	oAuthUserInfoReq, err := a.config.Client(context.Background(), oAuthToken).Get(gitHubUserURL)
 	if err != nil {
 		return nil, errors.Wrap(err, "could not get user data")
 	}
diff --git a/internal/util/config.go b/internal/util/config.go
index 29454e1..6ea4e47 100644
--- a/internal/util/config.go
+++ b/internal/util/config.go
@@ -43,6 +43,7 @@ type redisConf struct {
 type oAuthConf struct {
 	ClientID     string `yaml:"ClientID" env:"CLIENT_ID"`
 	ClientSecret string `yaml:"ClientSecret" env:"CLIENT_SECRET"`
+	EndpointURL  string `yaml:"EndPointURL" env:"ENDPOINT_URL"` // optional for only GitHub
 }
 
 type proxyAuthConf struct {