From b783caaaeddaee61384b963ce48bfe385a65b9a5 Mon Sep 17 00:00:00 2001
From: Gyula Voros <gyulavoros87@gmail.com>
Date: Thu, 17 Nov 2016 05:41:53 +0100
Subject: [PATCH] Filter empty headers (#1239)
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* Filter empty headers
Some web servers (e.g. Jetty 9.3) don’t like HTTP headers with empty values. This commit filters header replacements with zero length.
* Extend tests to verify removal of empty headers
* Handle add-header case
* Change - Use short variable assignment
---
caddyhttp/proxy/proxy.go | 10 ++++++++--
caddyhttp/proxy/proxy_test.go | 12 ++++++++++++
2 files changed, 20 insertions(+), 2 deletions(-)
diff --git a/caddyhttp/proxy/proxy.go b/caddyhttp/proxy/proxy.go
index 11f2d5d01..fe959791b 100644
--- a/caddyhttp/proxy/proxy.go
+++ b/caddyhttp/proxy/proxy.go
@@ -287,12 +287,18 @@ func mutateHeadersByRules(headers, rules http.Header, repl httpserver.Replacer)
for ruleField, ruleValues := range rules {
if strings.HasPrefix(ruleField, "+") {
for _, ruleValue := range ruleValues {
- headers.Add(strings.TrimPrefix(ruleField, "+"), repl.Replace(ruleValue))
+ replacement := repl.Replace(ruleValue)
+ if len(replacement) > 0 {
+ headers.Add(strings.TrimPrefix(ruleField, "+"), replacement)
+ }
}
} else if strings.HasPrefix(ruleField, "-") {
headers.Del(strings.TrimPrefix(ruleField, "-"))
} else if len(ruleValues) > 0 {
- headers.Set(ruleField, repl.Replace(ruleValues[len(ruleValues)-1]))
+ replacement := repl.Replace(ruleValues[len(ruleValues)-1])
+ if len(replacement) > 0 {
+ headers.Set(ruleField, replacement)
+ }
}
}
}
diff --git a/caddyhttp/proxy/proxy_test.go b/caddyhttp/proxy/proxy_test.go
index 290cae938..fe3772786 100644
--- a/caddyhttp/proxy/proxy_test.go
+++ b/caddyhttp/proxy/proxy_test.go
@@ -407,8 +407,10 @@ func TestUpstreamHeadersUpdate(t *testing.T) {
"Upgrade": {"{>Upgrade}"},
"+Merge-Me": {"Merge-Value"},
"+Add-Me": {"Add-Value"},
+ "+Add-Empty": {"{}"},
"-Remove-Me": {""},
"Replace-Me": {"{hostname}"},
+ "Clear-Me": {""},
"Host": {"{>Host}"},
}
// set up proxy
@@ -448,6 +450,11 @@ func TestUpstreamHeadersUpdate(t *testing.T) {
headerKey, expect, got)
}
+ headerKey = "Add-Empty"
+ if _, ok := actualHeaders[headerKey]; ok {
+ t.Errorf("Request sent to upstream backend should not contain empty %v header", headerKey)
+ }
+
headerKey = "Remove-Me"
if _, ok := actualHeaders[headerKey]; ok {
t.Errorf("Request sent to upstream backend should not contain %v header", headerKey)
@@ -461,6 +468,11 @@ func TestUpstreamHeadersUpdate(t *testing.T) {
headerKey, expect, got)
}
+ headerKey = "Clear-Me"
+ if _, ok := actualHeaders[headerKey]; ok {
+ t.Errorf("Request sent to upstream backend should not contain empty %v header", headerKey)
+ }
+
if actualHost != expectHost {
t.Errorf("Request sent to upstream backend should have value of Host with %s, but got %s", expectHost, actualHost)
}