outpost: use same http client for api requests and oauth token redeeming

Signed-off-by: Jens Langhammer <jens.langhammer@beryju.org>

outpost/pkg/proxy/api_bundle.go

@@ -141,7 +141,7 @@ func (pb *providerBundle) Build(provider api.ProxyOutpostConfig) {
 		log.Printf("%s", err)
 		os.Exit(1)
 	}
-	oauthproxy, err := NewOAuthProxy(opts, provider)
+	oauthproxy, err := NewOAuthProxy(opts, provider, pb.s.ak.Client.GetConfig().HTTPClient)
 	if err != nil {
 		log.Errorf("ERROR: Failed to initialise OAuth2 Proxy: %v", err)
 		os.Exit(1)

outpost/pkg/proxy/oauth.go

@@ -32,12 +32,22 @@ func (p *OAuthProxy) GetRedirectURI(host string) string {
 	return u.String()
 }
 
+// HTTPClient is the context key to use with golang.org/x/net/context's
+// WithValue function to associate an *http.Client value with a context.
+var HTTPClient ContextKey
+
+// ContextKey is just an empty struct. It exists so HTTPClient can be
+// an immutable public variable with a unique type. It's immutable
+// because nobody else can create a ContextKey, being unexported.
+type ContextKey struct{}
+
 func (p *OAuthProxy) redeemCode(ctx context.Context, host, code string) (s *sessionsapi.SessionState, err error) {
 	if code == "" {
 		return nil, errors.New("missing code")
 	}
 	redirectURI := p.GetRedirectURI(host)
-	s, err = p.provider.Redeem(ctx, redirectURI, code)
+	redeemCtx := context.WithValue(ctx, HTTPClient, p.client)
+	s, err = p.provider.Redeem(redeemCtx, redirectURI, code)
 	if err != nil {
 		return
 	}

outpost/pkg/proxy/proxy.go

@@ -44,6 +44,8 @@ var (
 
 // OAuthProxy is the main authentication proxy
 type OAuthProxy struct {
+	client *http.Client
+
 	CookieSeed     string
 	CookieName     string
 	CSRFCookieName string
@@ -94,7 +96,7 @@ type OAuthProxy struct {
 }
 
 // NewOAuthProxy creates a new instance of OAuthProxy from the options provided
-func NewOAuthProxy(opts *options.Options, provider api.ProxyOutpostConfig) (*OAuthProxy, error) {
+func NewOAuthProxy(opts *options.Options, provider api.ProxyOutpostConfig, c *http.Client) (*OAuthProxy, error) {
 	logger := log.WithField("logger", "authentik.outpost.proxy").WithField("provider", provider.Name)
 	sessionStore, err := sessions.NewSessionStore(&opts.Session, &opts.Cookie)
 	if err != nil {
@@ -122,6 +124,7 @@ func NewOAuthProxy(opts *options.Options, provider api.ProxyOutpostConfig) (*OAu
 	sessionChain := buildSessionChain(opts, sessionStore)
 
 	return &OAuthProxy{
+		client:         c,
 		CookieName:     opts.Cookie.Name,
 		CSRFCookieName: fmt.Sprintf("%v_%v", opts.Cookie.Name, "csrf"),
 		CookieSeed:     opts.Cookie.Secret,