Add trailer support (#1165)

* Add trailer support

* fix issue and add documentation

* remove redundant code

* add error return for add/set trailer method

* fix lint error

* fix bad trailer error return issue and update bad content-length error

* update errNonNumericChars

* update errNonNumericChars

* fix issue about error and fix typo

1 files changed, 29 insertions, 21 deletions

diff --git a/strings.go b/strings.go
index e28eaac..e4fb08b 100644
--- a/strings.go
+++ b/strings.go
@@ -20,31 +20,39 @@ var (
 	strColon            = []byte(":")
 	strColonSlashSlash  = []byte("://")
 	strColonSpace       = []byte(": ")
+	strCommaSpace       = []byte(", ")
 	strGMT              = []byte("GMT")
 
 	strResponseContinue = []byte("HTTP/1.1 100 Continue\r\n\r\n")
 
-	strExpect           = []byte(HeaderExpect)
-	strConnection       = []byte(HeaderConnection)
-	strContentLength    = []byte(HeaderContentLength)
-	strContentType      = []byte(HeaderContentType)
-	strDate             = []byte(HeaderDate)
-	strHost             = []byte(HeaderHost)
-	strReferer          = []byte(HeaderReferer)
-	strServer           = []byte(HeaderServer)
-	strTransferEncoding = []byte(HeaderTransferEncoding)
-	strContentEncoding  = []byte(HeaderContentEncoding)
-	strAcceptEncoding   = []byte(HeaderAcceptEncoding)
-	strUserAgent        = []byte(HeaderUserAgent)
-	strCookie           = []byte(HeaderCookie)
-	strSetCookie        = []byte(HeaderSetCookie)
-	strLocation         = []byte(HeaderLocation)
-	strIfModifiedSince  = []byte(HeaderIfModifiedSince)
-	strLastModified     = []byte(HeaderLastModified)
-	strAcceptRanges     = []byte(HeaderAcceptRanges)
-	strRange            = []byte(HeaderRange)
-	strContentRange     = []byte(HeaderContentRange)
-	strAuthorization    = []byte(HeaderAuthorization)
+	strExpect             = []byte(HeaderExpect)
+	strConnection         = []byte(HeaderConnection)
+	strContentLength      = []byte(HeaderContentLength)
+	strContentType        = []byte(HeaderContentType)
+	strDate               = []byte(HeaderDate)
+	strHost               = []byte(HeaderHost)
+	strReferer            = []byte(HeaderReferer)
+	strServer             = []byte(HeaderServer)
+	strTransferEncoding   = []byte(HeaderTransferEncoding)
+	strContentEncoding    = []byte(HeaderContentEncoding)
+	strAcceptEncoding     = []byte(HeaderAcceptEncoding)
+	strUserAgent          = []byte(HeaderUserAgent)
+	strCookie             = []byte(HeaderCookie)
+	strSetCookie          = []byte(HeaderSetCookie)
+	strLocation           = []byte(HeaderLocation)
+	strIfModifiedSince    = []byte(HeaderIfModifiedSince)
+	strLastModified       = []byte(HeaderLastModified)
+	strAcceptRanges       = []byte(HeaderAcceptRanges)
+	strRange              = []byte(HeaderRange)
+	strContentRange       = []byte(HeaderContentRange)
+	strAuthorization      = []byte(HeaderAuthorization)
+	strTE                 = []byte(HeaderTE)
+	strTrailer            = []byte(HeaderTrailer)
+	strMaxForwards        = []byte(HeaderMaxForwards)
+	strProxyConnection    = []byte(HeaderProxyConnection)
+	strProxyAuthenticate  = []byte(HeaderProxyAuthenticate)
+	strProxyAuthorization = []byte(HeaderProxyAuthorization)
+	strWWWAuthenticate    = []byte(HeaderWWWAuthenticate)
 
 	strCookieExpires        = []byte("expires")
 	strCookieDomain         = []byte("domain")