Merge pull request #1029 from oauth2-proxy/error-pages

Refactor error page rendering and allow debug messages on error

CHANGELOG.md

@@ -8,6 +8,7 @@
 
 ## Changes since v7.0.1
 
+- [#1029](https://github.com/oauth2-proxy/oauth2-proxy/pull/1029) Refactor error page rendering and allow debug messages on error (@JoelSpeed)
 - [#1028](https://github.com/oauth2-proxy/oauth2-proxy/pull/1028) Refactor templates, update theme and provide styled error pages (@JoelSpeed)
 - [#1039](https://github.com/oauth2-proxy/oauth2-proxy/pull/1039) Ensure errors in tests are logged to the GinkgoWriter (@JoelSpeed)
 

docs/docs/configuration/overview.md

@@ -115,6 +115,7 @@ An example [oauth2-proxy.cfg](https://github.com/oauth2-proxy/oauth2-proxy/blob/
 | `--set-xauthrequest` | bool | set X-Auth-Request-User, X-Auth-Request-Groups, X-Auth-Request-Email and X-Auth-Request-Preferred-Username response headers (useful in Nginx auth_request mode). When used with `--pass-access-token`, X-Auth-Request-Access-Token is added to response headers.  | false |
 | `--set-authorization-header` | bool | set Authorization Bearer response header (useful in Nginx auth_request mode) | false |
 | `--set-basic-auth` | bool | set HTTP Basic Auth information in response (useful in Nginx auth_request mode) | false |
+| `--show-debug-on-error` | bool | show detailed error information on error pages (WARNING: this may contain sensitive information - do not use in production) | false |
 | `--signature-key` | string | GAP-Signature request signature key (algorithm:secretkey) | |
 | `--silence-ping-logging` | bool | disable logging of requests to ping endpoint | false |
 | `--skip-auth-preflight` | bool | will skip authentication for OPTIONS requests | false |

oauthproxy.go

@@ -108,6 +108,7 @@ type OAuthProxy struct {
 	sessionChain alice.Chain
 	headersChain alice.Chain
 	preAuthChain alice.Chain
+	errorPage    *app.ErrorPage
 }
 
 // NewOAuthProxy creates a new instance of OAuthProxy from the options provided
@@ -121,8 +122,16 @@ func NewOAuthProxy(opts *options.Options, validator func(string) bool) (*OAuthPr
 	if err != nil {
 		return nil, fmt.Errorf("error loading templates: %v", err)
 	}
-	proxyErrorHandler := upstream.NewProxyErrorHandler(templates.Lookup("error.html"), opts.ProxyPrefix)
+
-	upstreamProxy, err := upstream.NewProxy(opts.UpstreamServers, opts.GetSignatureData(), proxyErrorHandler)
+	errorPage := &app.ErrorPage{
+		Template:    templates.Lookup("error.html"),
+		ProxyPrefix: opts.ProxyPrefix,
+		Footer:      opts.Templates.Footer,
+		Version:     VERSION,
+		Debug:       opts.Templates.Debug,
+	}
+
+	upstreamProxy, err := upstream.NewProxy(opts.UpstreamServers, opts.GetSignatureData(), errorPage.ProxyErrorHandler)
 	if err != nil {
 		return nil, fmt.Errorf("error initialising upstream proxy: %v", err)
 	}
@@ -224,6 +233,7 @@ func NewOAuthProxy(opts *options.Options, validator func(string) bool) (*OAuthPr
 		sessionChain:        sessionChain,
 		headersChain:        headersChain,
 		preAuthChain:        preAuthChain,
+		errorPage:           errorPage,
 	}, nil
 }
 
@@ -507,14 +517,14 @@ func (p *OAuthProxy) RobotsTxt(rw http.ResponseWriter, req *http.Request) {
 	_, err := fmt.Fprintf(rw, "User-agent: *\nDisallow: /")
 	if err != nil {
 		logger.Printf("Error writing robots.txt: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", err.Error())
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 		return
 	}
 	rw.WriteHeader(http.StatusOK)
 }
 
 // ErrorPage writes an error response
-func (p *OAuthProxy) ErrorPage(rw http.ResponseWriter, req *http.Request, code int, title string, message string) {
+func (p *OAuthProxy) ErrorPage(rw http.ResponseWriter, req *http.Request, code int, appError string, messages ...interface{}) {
 	redirectURL, err := p.getAppRedirect(req)
 	if err != nil {
 		logger.Errorf("Error obtaining redirect: %v", err)
@@ -523,32 +533,7 @@ func (p *OAuthProxy) ErrorPage(rw http.ResponseWriter, req *http.Request, code i
 		redirectURL = "/"
 	}
 
-	rw.WriteHeader(code)
+	p.errorPage.Render(rw, code, redirectURL, appError, messages...)
-
-	// We allow unescaped template.HTML since it is user configured options
-	/* #nosec G203 */
-	t := struct {
-		Title       string
-		Message     string
-		ProxyPrefix string
-		StatusCode  int
-		Redirect    string
-		Footer      template.HTML
-		Version     string
-	}{
-		Title:       title,
-		Message:     message,
-		ProxyPrefix: p.ProxyPrefix,
-		StatusCode:  code,
-		Redirect:    redirectURL,
-		Footer:      template.HTML(p.Footer),
-		Version:     VERSION,
-	}
-
-	if err := p.templates.ExecuteTemplate(rw, "error.html", t); err != nil {
-		logger.Printf("Error rendering error.html template: %v", err)
-		http.Error(rw, "Internal Server Error", http.StatusInternalServerError)
-	}
 }
 
 // IsAllowedRequest is used to check if auth should be skipped for this request
@@ -593,7 +578,7 @@ func (p *OAuthProxy) SignInPage(rw http.ResponseWriter, req *http.Request, code
 	err := p.ClearSessionCookie(rw, req)
 	if err != nil {
 		logger.Printf("Error clearing session cookie: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", err.Error())
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 		return
 	}
 	rw.WriteHeader(code)
@@ -601,7 +586,7 @@ func (p *OAuthProxy) SignInPage(rw http.ResponseWriter, req *http.Request, code
 	redirectURL, err := p.getAppRedirect(req)
 	if err != nil {
 		logger.Errorf("Error obtaining redirect: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", err.Error())
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 		return
 	}
 
@@ -634,7 +619,7 @@ func (p *OAuthProxy) SignInPage(rw http.ResponseWriter, req *http.Request, code
 	err = p.templates.ExecuteTemplate(rw, "sign_in.html", t)
 	if err != nil {
 		logger.Printf("Error rendering sign_in.html template: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", err.Error())
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 	}
 }
 
@@ -662,7 +647,7 @@ func (p *OAuthProxy) SignIn(rw http.ResponseWriter, req *http.Request) {
 	redirect, err := p.getAppRedirect(req)
 	if err != nil {
 		logger.Errorf("Error obtaining redirect: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", err.Error())
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 		return
 	}
 
@@ -672,7 +657,7 @@ func (p *OAuthProxy) SignIn(rw http.ResponseWriter, req *http.Request) {
 		err = p.SaveSession(rw, req, session)
 		if err != nil {
 			logger.Printf("Error saving session: %v", err)
-			p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", err.Error())
+			p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 			return
 		}
 		http.Redirect(rw, req, redirect, http.StatusFound)
@@ -711,7 +696,7 @@ func (p *OAuthProxy) UserInfo(rw http.ResponseWriter, req *http.Request) {
 	err = json.NewEncoder(rw).Encode(userInfo)
 	if err != nil {
 		logger.Printf("Error encoding user info: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", err.Error())
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 	}
 }
 
@@ -720,13 +705,13 @@ func (p *OAuthProxy) SignOut(rw http.ResponseWriter, req *http.Request) {
 	redirect, err := p.getAppRedirect(req)
 	if err != nil {
 		logger.Errorf("Error obtaining redirect: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", err.Error())
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 		return
 	}
 	err = p.ClearSessionCookie(rw, req)
 	if err != nil {
 		logger.Errorf("Error clearing session cookie: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", err.Error())
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 		return
 	}
 	http.Redirect(rw, req, redirect, http.StatusFound)
@@ -738,14 +723,14 @@ func (p *OAuthProxy) OAuthStart(rw http.ResponseWriter, req *http.Request) {
 	nonce, err := encryption.Nonce()
 	if err != nil {
 		logger.Errorf("Error obtaining nonce: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", err.Error())
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 		return
 	}
 	p.SetCSRFCookie(rw, req, nonce)
 	redirect, err := p.getAppRedirect(req)
 	if err != nil {
 		logger.Errorf("Error obtaining redirect: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", err.Error())
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 		return
 	}
 	redirectURI := p.getOAuthRedirectURI(req)
@@ -761,34 +746,36 @@ func (p *OAuthProxy) OAuthCallback(rw http.ResponseWriter, req *http.Request) {
 	err := req.ParseForm()
 	if err != nil {
 		logger.Errorf("Error while parsing OAuth2 callback: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", err.Error())
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 		return
 	}
 	errorString := req.Form.Get("error")
 	if errorString != "" {
 		logger.Errorf("Error while parsing OAuth2 callback: %s", errorString)
-		p.ErrorPage(rw, req, http.StatusForbidden, "Permission Denied", errorString)
+		message := fmt.Sprintf("Login Failed: The upstream identity provider returned an error: %s", errorString)
+		// Set the debug message and override the non debug message to be the same for this case
+		p.ErrorPage(rw, req, http.StatusForbidden, message, message)
 		return
 	}
 
 	session, err := p.redeemCode(req)
 	if err != nil {
 		logger.Errorf("Error redeeming code during OAuth2 callback: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", "Internal Error")
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 		return
 	}
 
 	err = p.enrichSessionState(req.Context(), session)
 	if err != nil {
 		logger.Errorf("Error creating session during OAuth2 callback: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", "Internal Error")
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 		return
 	}
 
 	state := strings.SplitN(req.Form.Get("state"), ":", 2)
 	if len(state) != 2 {
 		logger.Error("Error while parsing OAuth2 state: invalid length")
-		p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", "Invalid State")
+		p.ErrorPage(rw, req, http.StatusInternalServerError, "State paremeter did not have expected length", "Login Failed: Invalid State after login.")
 		return
 	}
 	nonce := state[0]
@@ -796,13 +783,13 @@ func (p *OAuthProxy) OAuthCallback(rw http.ResponseWriter, req *http.Request) {
 	c, err := req.Cookie(p.CSRFCookieName)
 	if err != nil {
 		logger.PrintAuthf(session.Email, req, logger.AuthFailure, "Invalid authentication via OAuth2: unable to obtain CSRF cookie")
-		p.ErrorPage(rw, req, http.StatusForbidden, "Permission Denied", err.Error())
+		p.ErrorPage(rw, req, http.StatusForbidden, err.Error(), "Login Failed: Unable to find a valid CSRF token. Please try again.")
 		return
 	}
 	p.ClearCSRFCookie(rw, req)
 	if c.Value != nonce {
 		logger.PrintAuthf(session.Email, req, logger.AuthFailure, "Invalid authentication via OAuth2: CSRF token mismatch, potential attack")
-		p.ErrorPage(rw, req, http.StatusForbidden, "Permission Denied", "CSRF Failed")
+		p.ErrorPage(rw, req, http.StatusForbidden, "CSRF token mismatch, potential attack", "Login Failed: Unable to find a valid CSRF token. Please try again.")
 		return
 	}
 
@@ -820,13 +807,13 @@ func (p *OAuthProxy) OAuthCallback(rw http.ResponseWriter, req *http.Request) {
 		err := p.SaveSession(rw, req, session)
 		if err != nil {
 			logger.Errorf("Error saving session state for %s: %v", remoteAddr, err)
-			p.ErrorPage(rw, req, http.StatusInternalServerError, "Internal Server Error", err.Error())
+			p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
 			return
 		}
 		http.Redirect(rw, req, redirect, http.StatusFound)
 	} else {
 		logger.PrintAuthf(session.Email, req, logger.AuthFailure, "Invalid authentication via OAuth2: unauthorized")
-		p.ErrorPage(rw, req, http.StatusForbidden, "Permission Denied", "Invalid Account")
+		p.ErrorPage(rw, req, http.StatusForbidden, "Invalid session: unauthorized")
 	}
 }
 
@@ -908,13 +895,12 @@ func (p *OAuthProxy) Proxy(rw http.ResponseWriter, req *http.Request) {
 		}
 
 	case ErrAccessDenied:
-		p.ErrorPage(rw, req, http.StatusUnauthorized, "Permission Denied", "Unauthorized")
+		p.ErrorPage(rw, req, http.StatusForbidden, "The session failed authorization checks")
 
 	default:
 		// unknown error
 		logger.Errorf("Unexpected internal error: %v", err)
-		p.ErrorPage(rw, req, http.StatusInternalServerError,
+		p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())
-			"Internal Error", "Internal Error")
 	}
 }
 

oauthproxy_test.go

@@ -2815,7 +2815,7 @@ func TestProxyAllowedGroups(t *testing.T) {
 			test.proxy.ServeHTTP(test.rw, test.req)
 
 			if tt.expectUnauthorized {
-				assert.Equal(t, http.StatusUnauthorized, test.rw.Code)
+				assert.Equal(t, http.StatusForbidden, test.rw.Code)
 			} else {
 				assert.Equal(t, http.StatusOK, test.rw.Code)
 			}

pkg/apis/options/app.go

@@ -22,6 +22,12 @@ type Templates struct {
 	// password form if a static passwords file (htpasswd file) has been
 	// configured.
 	DisplayLoginForm bool `flag:"display-htpasswd-form" cfg:"display_htpasswd_form"`
+
+	// Debug renders detailed errors when an error page is shown.
+	// It is not advised to use this in production as errors may contain sensitive
+	// information.
+	// Use only for diagnosing backend errors.
+	Debug bool `flag:"show-debug-on-error" cfg:"show-debug-on-error"`
 }
 
 func templatesFlagSet() *pflag.FlagSet {
@@ -31,6 +37,7 @@ func templatesFlagSet() *pflag.FlagSet {
 	flagSet.String("banner", "", "custom banner string. Use \"-\" to disable default banner.")
 	flagSet.String("footer", "", "custom footer string. Use \"-\" to disable default footer.")
 	flagSet.Bool("display-htpasswd-form", true, "display username / password login form if an htpasswd file is provided")
+	flagSet.Bool("show-debug-on-error", false, "show detailed error information on error pages (WARNING: this may contain sensitive information - do not use in production)")
 
 	return flagSet
 }

pkg/app/error_page.go

@@ -0,0 +1,97 @@
+package app
+
+import (
+	"fmt"
+	"html/template"
+	"net/http"
+
+	"github.com/oauth2-proxy/oauth2-proxy/v7/pkg/logger"
+)
+
+// errorMessages are default error messages for each of the the different
+// http status codes expected to be rendered in the error page.
+var errorMessages = map[int]string{
+	http.StatusInternalServerError: "Oops! Something went wrong. For more information contact your server administrator.",
+	http.StatusNotFound:            "We could not find the resource you were looking for.",
+	http.StatusForbidden:           "You do not have permission to access this resource.",
+	http.StatusUnauthorized:        "You need to be logged in to access this resource.",
+}
+
+// ErrorPage is used to render error pages.
+type ErrorPage struct {
+	// Template is the error page HTML template.
+	Template *template.Template
+
+	// ProxyPrefix is the prefix under which OAuth2 Proxy pages are served.
+	ProxyPrefix string
+
+	// Footer is the footer to be displayed at the bottom of the page.
+	// If not set, a default footer will be used.
+	Footer string
+
+	// Version is the OAuth2 Proxy version to be used in the default footer.
+	Version string
+
+	// Debug determines whether errors pages should be rendered with detailed
+	// errors.
+	Debug bool
+}
+
+// Render writes an error page to the given response writer.
+// It uses the passed redirectURL to give users the option to go back to where
+// they originally came from or try signing in again.
+func (e *ErrorPage) Render(rw http.ResponseWriter, status int, redirectURL string, appError string, messages ...interface{}) {
+	rw.WriteHeader(status)
+
+	// We allow unescaped template.HTML since it is user configured options
+	/* #nosec G203 */
+	data := struct {
+		Title       string
+		Message     string
+		ProxyPrefix string
+		StatusCode  int
+		Redirect    string
+		Footer      template.HTML
+		Version     string
+	}{
+		Title:       http.StatusText(status),
+		Message:     e.getMessage(status, appError, messages...),
+		ProxyPrefix: e.ProxyPrefix,
+		StatusCode:  status,
+		Redirect:    redirectURL,
+		Footer:      template.HTML(e.Footer),
+		Version:     e.Version,
+	}
+
+	if err := e.Template.Execute(rw, data); err != nil {
+		logger.Printf("Error rendering error template: %v", err)
+		http.Error(rw, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
+	}
+}
+
+// ProxyErrorHandler is used by the upstream ReverseProxy to render error pages
+// when there are issues with upstream servers.
+// It is expected to always render a bad gateway error.
+func (e *ErrorPage) ProxyErrorHandler(rw http.ResponseWriter, req *http.Request, proxyErr error) {
+	logger.Errorf("Error proxying to upstream server: %v", proxyErr)
+	e.Render(rw, http.StatusBadGateway, "", proxyErr.Error(), "There was a problem connecting to the upstream server.")
+}
+
+// getMessage creates the message for the template parameters.
+// If the ErrorPage.Debug is enabled, the application error takes precedence.
+// Otherwise, any messages will be used.
+// The first message is expected to be a format string.
+// If no messages are supplied, a default error message will be used.
+func (e *ErrorPage) getMessage(status int, appError string, messages ...interface{}) string {
+	if e.Debug {
+		return appError
+	}
+	if len(messages) > 0 {
+		format := fmt.Sprintf("%v", messages[0])
+		return fmt.Sprintf(format, messages[1:]...)
+	}
+	if msg, ok := errorMessages[status]; ok {
+		return msg
+	}
+	return "Unknown error"
+}

pkg/app/error_page_test.go

@@ -0,0 +1,101 @@
+package app
+
+import (
+	"errors"
+	"html/template"
+	"io/ioutil"
+	"net/http/httptest"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Error Page", func() {
+	var errorPage *ErrorPage
+
+	BeforeEach(func() {
+		tmpl, err := template.New("").Parse("{{.Title}} {{.Message}} {{.ProxyPrefix}} {{.StatusCode}} {{.Redirect}} {{.Footer}} {{.Version}}")
+		Expect(err).ToNot(HaveOccurred())
+
+		errorPage = &ErrorPage{
+			Template:    tmpl,
+			ProxyPrefix: "/prefix/",
+			Footer:      "Custom Footer Text",
+			Version:     "v0.0.0-test",
+		}
+	})
+
+	Context("Render", func() {
+		It("Writes the template to the response writer", func() {
+			recorder := httptest.NewRecorder()
+			errorPage.Render(recorder, 403, "/redirect", "Access Denied")
+
+			body, err := ioutil.ReadAll(recorder.Result().Body)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(string(body)).To(Equal("Forbidden You do not have permission to access this resource. /prefix/ 403 /redirect Custom Footer Text v0.0.0-test"))
+		})
+
+		It("With a different code, uses the stock message for the correct code", func() {
+			recorder := httptest.NewRecorder()
+			errorPage.Render(recorder, 500, "/redirect", "Access Denied")
+
+			body, err := ioutil.ReadAll(recorder.Result().Body)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(string(body)).To(Equal("Internal Server Error Oops! Something went wrong. For more information contact your server administrator. /prefix/ 500 /redirect Custom Footer Text v0.0.0-test"))
+		})
+
+		It("With a message override, uses the message", func() {
+			recorder := httptest.NewRecorder()
+			errorPage.Render(recorder, 403, "/redirect", "Access Denied", "An extra message: %s", "with more context.")
+
+			body, err := ioutil.ReadAll(recorder.Result().Body)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(string(body)).To(Equal("Forbidden An extra message: with more context. /prefix/ 403 /redirect Custom Footer Text v0.0.0-test"))
+		})
+	})
+
+	Context("ProxyErrorHandler", func() {
+		It("Writes a bad gateway error the response writer", func() {
+			req := httptest.NewRequest("", "/bad-gateway", nil)
+			recorder := httptest.NewRecorder()
+			errorPage.ProxyErrorHandler(recorder, req, errors.New("some upstream error"))
+
+			body, err := ioutil.ReadAll(recorder.Result().Body)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(string(body)).To(Equal("Bad Gateway There was a problem connecting to the upstream server. /prefix/ 502  Custom Footer Text v0.0.0-test"))
+		})
+	})
+
+	Context("With Debug enabled", func() {
+		BeforeEach(func() {
+			tmpl, err := template.New("").Parse("{{.Message}}")
+			Expect(err).ToNot(HaveOccurred())
+
+			errorPage.Template = tmpl
+			errorPage.Debug = true
+		})
+
+		Context("Render", func() {
+			It("Writes the detailed error in place of the message", func() {
+				recorder := httptest.NewRecorder()
+				errorPage.Render(recorder, 403, "/redirect", "Debug error")
+
+				body, err := ioutil.ReadAll(recorder.Result().Body)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(string(body)).To(Equal("Debug error"))
+			})
+		})
+
+		Context("ProxyErrorHandler", func() {
+			It("Writes a bad gateway error the response writer", func() {
+				req := httptest.NewRequest("", "/bad-gateway", nil)
+				recorder := httptest.NewRecorder()
+				errorPage.ProxyErrorHandler(recorder, req, errors.New("some upstream error"))
+
+				body, err := ioutil.ReadAll(recorder.Result().Body)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(string(body)).To(Equal("some upstream error"))
+			})
+		})
+	})
+})

pkg/app/templates.go

@@ -79,6 +79,7 @@ const (
   		</div>
       {{ end }}
 
+      {{ if .Redirect }}
       <hr>
 
       <div class="columns">
@@ -94,6 +95,7 @@ const (
           </form>
         </div>
       </div>
+      {{ end }}
 
     </div>
   </section>

pkg/upstream/proxy.go

@@ -2,7 +2,6 @@ package upstream
 
 import (
 	"fmt"
-	"html/template"
 	"net/http"
 	"net/url"
 
@@ -71,24 +70,3 @@ func (m *multiUpstreamProxy) registerHTTPUpstreamProxy(upstream options.Upstream
 	logger.Printf("mapping path %q => upstream %q", upstream.Path, upstream.URI)
 	m.serveMux.Handle(upstream.Path, newHTTPUpstreamProxy(upstream, u, sigData, errorHandler))
 }
-
-// NewProxyErrorHandler creates a ProxyErrorHandler using the template given.
-func NewProxyErrorHandler(errorTemplate *template.Template, proxyPrefix string) ProxyErrorHandler {
-	return func(rw http.ResponseWriter, req *http.Request, proxyErr error) {
-		logger.Errorf("Error proxying to upstream server: %v", proxyErr)
-		rw.WriteHeader(http.StatusBadGateway)
-		data := struct {
-			Title       string
-			Message     string
-			ProxyPrefix string
-		}{
-			Title:       "Bad Gateway",
-			Message:     "Error proxying to upstream server",
-			ProxyPrefix: proxyPrefix,
-		}
-		err := errorTemplate.Execute(rw, data)
-		if err != nil {
-			http.Error(rw, "Internal Server Error", http.StatusInternalServerError)
-		}
-	}
-}

pkg/upstream/proxy_test.go

@@ -4,7 +4,6 @@ import (
 	"crypto"
 	"encoding/json"
 	"fmt"
-	"html/template"
 	"net/http"
 	"net/http/httptest"
 
@@ -20,9 +19,10 @@ var _ = Describe("Proxy Suite", func() {
 	BeforeEach(func() {
 		sigData := &options.SignatureData{Hash: crypto.SHA256, Key: "secret"}
 
-		tmpl, err := template.New("").Parse("{{ .Title }}\n{{ .Message }}\n{{ .ProxyPrefix }}")
+		errorHandler := func(rw http.ResponseWriter, _ *http.Request, _ error) {
-		Expect(err).ToNot(HaveOccurred())
+			rw.WriteHeader(502)
-		errorHandler := NewProxyErrorHandler(tmpl, "prefix")
+			rw.Write([]byte("Proxy Error"))
+		}
 
 		ok := http.StatusOK
 
@@ -56,6 +56,7 @@ var _ = Describe("Proxy Suite", func() {
 			},
 		}
 
+		var err error
 		upstreamServer, err = NewProxy(upstreams, sigData, errorHandler)
 		Expect(err).ToNot(HaveOccurred())
 	})
@@ -143,7 +144,7 @@ var _ = Describe("Proxy Suite", func() {
 					gapUpstream: {"bad-http-backend"},
 				},
 				// This tests the error handler
-				raw: "Bad Gateway\nError proxying to upstream server\nprefix",
+				raw: "Proxy Error",
 			},
 		}),
 		Entry("with a request to the to an unregistered path", &proxyTableInput{