From 2cb6a515ac019bf5621a4d5bd54cf388f5d65e20 Mon Sep 17 00:00:00 2001
From: r <r@freesoftwareextremist.com>
Date: Sat, 3 Apr 2021 06:39:06 +0000
Subject: [PATCH] Update error page

- Add retry button for GET requests
- Only show signin button when it's a session error
---
 renderer/model.go    |  4 +++-
 service/service.go   | 10 ++++++++--
 service/transport.go |  8 ++++----
 templates/error.tmpl | 11 ++++++++---
 4 files changed, 23 insertions(+), 10 deletions(-)

diff --git a/renderer/model.go b/renderer/model.go
index 6b27998..d6cd6f3 100644
--- a/renderer/model.go
+++ b/renderer/model.go
@@ -34,7 +34,9 @@ type NavData struct {
 
 type ErrorData struct {
 	*CommonData
-	Error string
+	Err        string
+	Retry      bool
+	SessionErr bool
 }
 
 type HomePageData struct {
diff --git a/service/service.go b/service/service.go
index 1028765..a29345e 100644
--- a/service/service.go
+++ b/service/service.go
@@ -109,15 +109,21 @@ func (s *service) cdata(c *client, title string, count int, rinterval int,
 	return
 }
 
-func (s *service) ErrorPage(c *client, err error) error {
+func (s *service) ErrorPage(c *client, err error, retry bool) error {
 	var errStr string
+	var sessionErr bool
 	if err != nil {
 		errStr = err.Error()
+		if err == errInvalidSession || err == errInvalidCSRFToken {
+			sessionErr = true
+		}
 	}
 	cdata := s.cdata(nil, "error", 0, 0, "")
 	data := &renderer.ErrorData{
 		CommonData: cdata,
-		Error:      errStr,
+		Err:        errStr,
+		Retry:      retry,
+		SessionErr: sessionErr,
 	}
 	return s.renderer.Render(c.rctx, c.w, renderer.ErrorPage, data)
 }
diff --git a/service/transport.go b/service/transport.go
index 317ce5b..50bf9be 100644
--- a/service/transport.go
+++ b/service/transport.go
@@ -62,11 +62,11 @@ func redirect(c *client, url string) {
 func NewHandler(s *service, logger *log.Logger, staticDir string) http.Handler {
 	r := mux.NewRouter()
 
-	writeError := func(c *client, err error, t int) {
+	writeError := func(c *client, err error, t int, retry bool) {
 		switch t {
 		case HTML:
 			c.w.WriteHeader(http.StatusInternalServerError)
-			s.ErrorPage(c, err)
+			s.ErrorPage(c, err, retry)
 		case JSON:
 			c.w.WriteHeader(http.StatusInternalServerError)
 			json.NewEncoder(c.w).Encode(map[string]string{
@@ -110,13 +110,13 @@ func NewHandler(s *service, logger *log.Logger, staticDir string) http.Handler {
 
 			err = authenticate(c, at)
 			if err != nil {
-				writeError(c, err, rt)
+				writeError(c, err, rt, req.Method == http.MethodGet)
 				return
 			}
 
 			err = f(c)
 			if err != nil {
-				writeError(c, err, rt)
+				writeError(c, err, rt, req.Method == http.MethodGet)
 				return
 			}
 		}
diff --git a/templates/error.tmpl b/templates/error.tmpl
index fc925ca..c8da1e6 100644
--- a/templates/error.tmpl
+++ b/templates/error.tmpl
@@ -2,10 +2,15 @@
 {{template "header.tmpl" (WithContext .CommonData $.Ctx)}}
 <div class="page-title"> Error </div>
 
-<div class="error-text"> {{.Error}} </div>
+<div class="error-text"> {{.Err}} </div>
 <div>
-	<a href="/timeline/home">Home</a>
-	<a href="/signin" target="_top">Sign In</a>
+	<a href="/timeline/home">home</a>
+	{{if .Retry}}
+	<a href="{{$.Ctx.Referrer}}">retry</a>
+	{{end}}
+	{{if .SessionErr}}
+	<a href="/signin" target="_top">signin</a>
+	{{end}}
 </div>
 
 {{template "footer.tmpl"}}