From 42523ae9d9dae6a1d231cad0e448aeff2c2fbbab Mon Sep 17 00:00:00 2001
From: Florian Michel <52607335+flo-mic@users.noreply.github.com>
Date: Mon, 31 Jan 2022 06:40:58 +0100
Subject: [PATCH] Adds "Host" and "X-Forwarded-For" header options (#61)

---
 CHANGELOG.md                    |  1 +
 error-pages.yml                 |  4 ++++
 internal/http/core/errorpage.go |  2 ++
 internal/http/core/headers.go   |  6 ++++++
 internal/tpl/properties.go      |  2 ++
 internal/tpl/properties_test.go |  4 ++++
 templates/cats.html             |  8 ++++++++
 templates/ghost.html            |  8 ++++++++
 templates/hacker-terminal.html  |  2 ++
 templates/l7-dark.html          |  8 ++++++++
 templates/l7-light.html         |  8 ++++++++
 templates/shuffle.html          | 12 ++++++++++++
 test/hurl/code_502_xml.hurl     |  2 ++
 13 files changed, 67 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index aaf4fa0..faa81de 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,7 @@ The format is based on [Keep a Changelog][keepachangelog] and this project adher
 ### UNRELEASED
 
 - Go updated from `1.17.5` up to `1.17.6`
+- Add "Host" and "X-Forwarded-For" Header to error pages
 
 ## v2.4.0
 
diff --git a/error-pages.yml b/error-pages.yml
index 35d2047..08fdd80 100644
--- a/error-pages.yml
+++ b/error-pages.yml
@@ -21,7 +21,9 @@ formats:
         "message": {{ message | json }},
         "description": {{ description | json }}{{ if show_details }},
         "details": {
+          "host": {{ host | json }},
           "original_uri": {{ original_uri | json }},
+          "forwarded_for": {{ forwarded_for | json }},
           "namespace": {{ namespace | json }},
           "ingress_name": {{ ingress_name | json }},
           "service_name": {{ service_name | json }},
@@ -39,7 +41,9 @@ formats:
         <message>{{ message }}</message>
         <description>{{ description }}</description>{{ if show_details }}
         <details>
+          <host>{{ host }}</host>
           <originalURI>{{ original_uri }}</originalURI>
+          <forwardedFor>{{ forwarded_for }}</forwardedFor>
           <namespace>{{ namespace }}</namespace>
           <ingressName>{{ ingress_name }}</ingressName>
           <serviceName>{{ service_name }}</serviceName>
diff --git a/internal/http/core/errorpage.go b/internal/http/core/errorpage.go
index 851df0a..c118668 100644
--- a/internal/http/core/errorpage.go
+++ b/internal/http/core/errorpage.go
@@ -37,6 +37,8 @@ func RespondWithErrorPage( //nolint:funlen
 		props.ServiceName = string(ctx.Request.Header.Peek(ServiceName))
 		props.ServicePort = string(ctx.Request.Header.Peek(ServicePort))
 		props.RequestID = string(ctx.Request.Header.Peek(RequestID))
+		props.ForwardedFor = string(ctx.Request.Header.Peek(ForwardedFor))
+		props.Host = string(ctx.Request.Header.Peek(Host))
 	}
 
 	if page, exists := cfg.Pages[pageCode]; exists {
diff --git a/internal/http/core/headers.go b/internal/http/core/headers.go
index bbd9f64..18ee605 100644
--- a/internal/http/core/headers.go
+++ b/internal/http/core/headers.go
@@ -24,4 +24,10 @@ const (
 
 	// RequestID is a unique ID that identifies the request - same as for backend service
 	RequestID = "X-Request-ID"
+
+	// Forward-For identifies the user of this session
+	ForwardedFor = "X-Forwarded-For"
+
+	// Host identifies the hosts origin
+	Host = "Host"
 )
diff --git a/internal/tpl/properties.go b/internal/tpl/properties.go
index 69b098a..75b0f30 100644
--- a/internal/tpl/properties.go
+++ b/internal/tpl/properties.go
@@ -12,6 +12,8 @@ type Properties struct { // only string properties with a "token" tag, please
 	ServiceName        string `token:"service_name"`
 	ServicePort        string `token:"service_port"`
 	RequestID          string `token:"request_id"`
+	ForwardedFor       string `token:"forwarded_for"`
+	Host       		   string `token:"host"`
 	ShowRequestDetails bool
 }
 
diff --git a/internal/tpl/properties_test.go b/internal/tpl/properties_test.go
index d2d1e2a..6be28be 100644
--- a/internal/tpl/properties_test.go
+++ b/internal/tpl/properties_test.go
@@ -18,6 +18,8 @@ func TestProperties_Replaces(t *testing.T) {
 		ServiceName: "ddd",
 		ServicePort: "eee",
 		RequestID:   "fff",
+		ForwardedFor:"ggg",
+		Host:  		 "hhh",
 	}
 
 	r := props.Replaces()
@@ -31,6 +33,8 @@ func TestProperties_Replaces(t *testing.T) {
 	assert.Equal(t, "ddd", r["service_name"])
 	assert.Equal(t, "eee", r["service_port"])
 	assert.Equal(t, "fff", r["request_id"])
+	assert.Equal(t, "ggg", r["forwarded_for"])
+	assert.Equal(t, "hhh", r["host"])
 
 	props.Code, props.Message, props.Description = "", "", ""
 
diff --git a/templates/cats.html b/templates/cats.html
index b1dd80c..a08cf73 100644
--- a/templates/cats.html
+++ b/templates/cats.html
@@ -62,10 +62,18 @@
         {{ if show_details }}
         <div class="details">
             <table>
+                {{- if host }}<tr>
+                    <td class="name">Host</td>
+                    <td class="value">{{ host }}</td>
+                </tr>{{ end -}}
                 {{- if original_uri }}<tr>
                     <td class="name">Original URI</td>
                     <td class="value">{{ original_uri }}</td>
                 </tr>{{ end -}}
+                {{- if forwarded_for }}<tr>
+                    <td class="name">Forwarded for</td>
+                    <td class="value">{{ forwarded_for }}</td>
+                </tr>{{ end -}}
                 {{- if namespace }}<tr>
                     <td class="name">Namespace</td>
                     <td class="value">{{ namespace }}</td>
diff --git a/templates/ghost.html b/templates/ghost.html
index d9482a5..920c298 100644
--- a/templates/ghost.html
+++ b/templates/ghost.html
@@ -55,10 +55,18 @@
         {{ if show_details }}
         <div class="details">
             <table>
+                {{- if host }}<tr>
+                    <td class="name">Host</td>
+                    <td class="value">{{ host }}</td>
+                </tr>{{ end -}}
                 {{- if original_uri }}<tr>
                     <td class="name">Original URI</td>
                     <td class="value">{{ original_uri }}</td>
                 </tr>{{ end -}}
+                {{- if forwarded_for }}<tr>
+                    <td class="name">Forwarded for</td>
+                    <td class="value">{{ forwarded_for }}</td>
+                </tr>{{ end -}}
                 {{- if namespace }}<tr>
                     <td class="name">Namespace</td>
                     <td class="value">{{ namespace }}</td>
diff --git a/templates/hacker-terminal.html b/templates/hacker-terminal.html
index 11df5ce..828467d 100644
--- a/templates/hacker-terminal.html
+++ b/templates/hacker-terminal.html
@@ -150,7 +150,9 @@
     <p class="output">Good luck.</p>
     {{ if show_details }}
     <div class="details">
+        {{- if host }}<p class="output small">Host: <code>{{ host }}</code></p>{{ end -}}
         {{- if original_uri }}<p class="output small">Original URI: <code>{{ original_uri }}</code></p>{{ end -}}
+        {{- if forwarded_for }}<p class="output small">Forwarded for: <code>{{ forwarded_for }}</code></p>{{ end -}}
         {{- if namespace }}<p class="output small">Namespace: <code>{{ namespace }}</code></p>{{ end -}}
         {{- if ingress_name }}<p class="output small">Ingress name: <code>{{ ingress_name }}</code></p>{{ end -}}
         {{- if service_name }}<p class="output small">Service name: <code>{{ service_name }}</code></p>{{ end -}}
diff --git a/templates/l7-dark.html b/templates/l7-dark.html
index 846cd2a..68b94ed 100644
--- a/templates/l7-dark.html
+++ b/templates/l7-dark.html
@@ -40,10 +40,18 @@
         {{ if show_details }}
         <div class="details">
             <table>
+                {{- if host }}<tr>
+                    <td class="name">Host</td>
+                    <td class="value">{{ host }}</td>
+                </tr>{{ end -}}
                 {{- if original_uri }}<tr>
                     <td class="name">Original URI</td>
                     <td class="value">{{ original_uri }}</td>
                 </tr>{{ end -}}
+                {{- if forwarded_for }}<tr>
+                    <td class="name">Forwarded for</td>
+                    <td class="value">{{ forwarded_for }}</td>
+                </tr>{{ end -}}
                 {{- if namespace }}<tr>
                     <td class="name">Namespace</td>
                     <td class="value">{{ namespace }}</td>
diff --git a/templates/l7-light.html b/templates/l7-light.html
index 56a4678..60e1310 100644
--- a/templates/l7-light.html
+++ b/templates/l7-light.html
@@ -40,10 +40,18 @@
         {{ if show_details }}
         <div class="details">
             <table>
+                {{- if host }}<tr>
+                    <td class="name">Host</td>
+                    <td class="value">{{ host }}</td>
+                </tr>{{ end -}}
                 {{- if original_uri }}<tr>
                     <td class="name">Original URI</td>
                     <td class="value">{{ original_uri }}</td>
                 </tr>{{ end -}}
+                {{- if forwarded_for }}<tr>
+                    <td class="name">Forwarded for</td>
+                    <td class="value">{{ forwarded_for }}</td>
+                </tr>{{ end -}}
                 {{- if namespace }}<tr>
                     <td class="name">Namespace</td>
                     <td class="value">{{ namespace }}</td>
diff --git a/templates/shuffle.html b/templates/shuffle.html
index b703a37..5c64a28 100644
--- a/templates/shuffle.html
+++ b/templates/shuffle.html
@@ -76,12 +76,24 @@
         {{ if show_details }}
         <div class="hidden" id="details">
             <table>
+                {{- if host }}
+                <tr>
+                    <td class="name">Host:</td>
+                    <td class="value">{{ host }}</td>
+                </tr>
+                {{ end -}}
                 {{- if original_uri }}
                 <tr>
                     <td class="name">Original URI:</td>
                     <td class="value">{{ original_uri }}</td>
                 </tr>
                 {{ end -}}
+                {{- if forwarded_for }}
+                <tr>
+                    <td class="name">Forwarded for:</td>
+                    <td class="value">{{ forwarded_for }}</td>
+                </tr>
+                {{ end -}}
                 {{- if namespace }}
                 <tr>
                     <td class="name">Namespace:</td>
diff --git a/test/hurl/code_502_xml.hurl b/test/hurl/code_502_xml.hurl
index d9cec69..943e92b 100644
--- a/test/hurl/code_502_xml.hurl
+++ b/test/hurl/code_502_xml.hurl
@@ -22,6 +22,8 @@ xpath "string(//error/details/ingressName)" == "baz"
 xpath "string(//error/details/serviceName)" == "aaa"
 xpath "string(//error/details/servicePort)" == "bbb"
 xpath "string(//error/details/requestID)" == "ccc"
+xpath "string(//error/details/forwardedFor)" == "ddd"
+xpath "string(//error/details/host)" == "fff"
 xpath "string(//error/details/timestamp)" exists
 
 # X-Format in the action