From ff955c633aeef820ada6bf5ec300f23dc0344acb Mon Sep 17 00:00:00 2001
From: Darren Lee <darren@leeriggins.com>
Date: Tue, 15 Jun 2010 11:18:10 -0700
Subject: [PATCH] Add ability to rewrite arbitrary headers

---
 src/main/scala/fakehttp/Proxy.scala           |  2 +-
 .../interceptor/HeaderRewriting.scala         | 37 +++++++++++++++++++
 2 files changed, 38 insertions(+), 1 deletion(-)
 create mode 100644 src/main/scala/fakehttp/interceptor/HeaderRewriting.scala

diff --git a/src/main/scala/fakehttp/Proxy.scala b/src/main/scala/fakehttp/Proxy.scala
index d3546fb..2c9d36c 100644
--- a/src/main/scala/fakehttp/Proxy.scala
+++ b/src/main/scala/fakehttp/Proxy.scala
@@ -37,7 +37,7 @@ class Proxy(val interceptor: Interceptor, val port: Int, val sslMode: SslMode) {
 object Proxy {
   def main(args: Array[String]): Unit = {
     val port = args(0).toInt
-    val interceptor = new NoopInterceptor with HeaderBasedRedirection
+    val interceptor = new NoopInterceptor with HeaderBasedRedirection with HeaderRewriting
     val sslMode = new OpaqueSslMode() // ClearSslMode()
 
     val proxy = new Proxy(interceptor, port, sslMode)
diff --git a/src/main/scala/fakehttp/interceptor/HeaderRewriting.scala b/src/main/scala/fakehttp/interceptor/HeaderRewriting.scala
new file mode 100644
index 0000000..9e43e5b
--- /dev/null
+++ b/src/main/scala/fakehttp/interceptor/HeaderRewriting.scala
@@ -0,0 +1,37 @@
+package fakehttp.interceptor
+
+import org.jboss.netty.handler.codec.http._
+
+/**
+ * This trait adds header rewriting to the interceptor.
+ * 
+ * To use, define a header with prefix "X-Fakehttp-Header-Rewrite-{header}".  The value of this header will be written
+ * into the "{header}" header.  These X-Fakehttp-Header-Rewrite-* headers will then be removed.
+ * 
+ * @author darren
+ *
+ */
+trait HeaderRewriting extends Interceptor {
+  
+  import HeaderRewriting._
+  import scala.collection.JavaConversions._
+  
+  override abstract def intercept(request: HttpRequest): InterceptResult = {
+    request.getHeaderNames filter { 
+      _.startsWith(PREFIX) 
+    } foreach { header =>
+      val value = request.getHeader(header)
+      request.setHeader(header.substring(PREFIX_LENGTH), value)
+      System.err.println("Setting header [%s] to [%s]".format(header.substring(PREFIX_LENGTH), value))
+      request.removeHeader(header)
+    }
+    
+    super.intercept(request)
+  }
+  
+}
+
+object HeaderRewriting {
+  val PREFIX = "X-Fakehttp-Header-Rewrite-"
+  val PREFIX_LENGTH = PREFIX.length
+}