Allowing usage of https://github.<company>.com/api/v3

README.md

@@ -88,11 +88,11 @@ The GitHub auth provider supports two additional parameters to restrict authenti
 
 If you are using github enterprise, make sure you set the following to the appropriate url:
 
+    -github-api-url="https://<github domain>/api/v3/"
     -login-url="<enterprise github url>/login/oauth/authorize"
     -redeem-url="<enterprise github url>/login/oauth/access_token"
     -validate-url="<enterprise github api url>/user/emails"
 
-
 ### LinkedIn Auth Provider
 
 For LinkedIn, the registration steps are:

main.go

@@ -38,6 +38,7 @@ func main() {
 	flagSet.Var(&skipAuthRegex, "skip-auth-regex", "bypass authentication for requests path's that match (may be given multiple times)")
 
 	flagSet.Var(&emailDomains, "email-domain", "authenticate emails with the specified domain (may be given multiple times). Use * to authenticate any email")
+	flagSet.String("github-api-url", "", "github api url to configure github enterprise endpoint")
 	flagSet.String("github-org", "", "restrict logins to members of this organisation")
 	flagSet.String("github-team", "", "restrict logins to members of this team")
 	flagSet.Var(&googleGroups, "google-group", "restrict logins to members of this google group (may be given multiple times).")

options.go

@@ -28,6 +28,7 @@ type Options struct {
 	EmailDomains             []string `flag:"email-domain" cfg:"email_domains"`
 	GitHubOrg                string   `flag:"github-org" cfg:"github_org"`
 	GitHubTeam               string   `flag:"github-team" cfg:"github_team"`
+	GitHubApiUrl             string	  `flag:"github-api-url" cfg:"github_api_url"`
 	GoogleGroups             []string `flag:"google-group" cfg:"google_group"`
 	GoogleAdminEmail         string   `flag:"google-admin-email" cfg:"google_admin_email"`
 	GoogleServiceAccountJSON string   `flag:"google-service-account-json" cfg:"google_service_account_json"`
@@ -210,6 +211,7 @@ func parseProviderInfo(o *Options, msgs []string) []string {
 	switch p := o.provider.(type) {
 	case *providers.GitHubProvider:
 		p.SetOrgTeam(o.GitHubOrg, o.GitHubTeam)
+		p.SetApiUrl(o.GitHubApiUrl)
 	case *providers.GoogleProvider:
 		if o.GoogleServiceAccountJSON != "" {
 			file, err := os.Open(o.GoogleServiceAccountJSON)

providers/github.go

@@ -7,12 +7,14 @@ import (
 	"log"
 	"net/http"
 	"net/url"
+	"strings"
 )
 
 type GitHubProvider struct {
 	*ProviderData
-	Org  string
-	Team string
+	Org    string
+	Team   string
+	ApiUrl string
 }
 
 func NewGitHubProvider(p *ProviderData) *GitHubProvider {
@@ -51,6 +53,16 @@ func (p *GitHubProvider) SetOrgTeam(org, team string) {
 	}
 }
 
+func (p *GitHubProvider) SetApiUrl(uri string) {
+	// Expecting BaseUrl to be https://github.<domain>/api/v3/
+	p.ApiUrl = uri
+	if len(p.ApiUrl) <= 0 {
+		p.ApiUrl = fmt.Sprintf("%s://%s/", p.ValidateURL.Scheme, p.ValidateURL.Host)
+	} else if !strings.HasSuffix(p.ApiUrl, "/") {
+		p.ApiUrl = fmt.Sprintf("%s/", p.ApiUrl)
+	}
+}
+
 func (p *GitHubProvider) hasOrg(accessToken string) (bool, error) {
 	// https://developer.github.com/v3/orgs/#list-your-organizations
 
@@ -62,8 +74,7 @@ func (p *GitHubProvider) hasOrg(accessToken string) (bool, error) {
 		"access_token": {accessToken},
 		"limit":        {"100"},
 	}
-
-	endpoint := p.ValidateURL.Scheme + "://"  + p.ValidateURL.Host + "/user/orgs?" + params.Encode()
+	endpoint := p.getEndpoint("user/orgs", params)
 	req, _ := http.NewRequest("GET", endpoint, nil)
 	req.Header.Set("Accept", "application/vnd.github.v3+json")
 	resp, err := http.DefaultClient.Do(req)
@@ -112,8 +123,7 @@ func (p *GitHubProvider) hasOrgAndTeam(accessToken string) (bool, error) {
 		"access_token": {accessToken},
 		"limit":        {"100"},
 	}
-
-	endpoint := p.ValidateURL.Scheme + "://" + p.ValidateURL.Host + "/user/teams?" + params.Encode()
+	endpoint := p.getEndpoint("user/teams", params)
 	req, _ := http.NewRequest("GET", endpoint, nil)
 	req.Header.Set("Accept", "application/vnd.github.v3+json")
 	resp, err := http.DefaultClient.Do(req)
@@ -183,7 +193,7 @@ func (p *GitHubProvider) GetEmailAddress(s *SessionState) (string, error) {
 	params := url.Values{
 		"access_token": {s.AccessToken},
 	}
-	endpoint := p.ValidateURL.Scheme + "://" + p.ValidateURL.Host + p.ValidateURL.Path + "?" + params.Encode()
+	endpoint := fmt.Sprintf("%s?%s", p.ValidateURL.String(), params.Encode())
 	resp, err := http.DefaultClient.Get(endpoint)
 	if err != nil {
 		return "", err
@@ -212,3 +222,7 @@ func (p *GitHubProvider) GetEmailAddress(s *SessionState) (string, error) {
 
 	return "", nil
 }
+
+func (p *GitHubProvider) getEndpoint(path string, params url.Values) string {
+	return fmt.Sprintf("%s%s?%s", p.ApiUrl, path, params.Encode())
+}