http: add uniqueHeaders option to request and createServer

PR-URL: #41397 Reviewed-By: Robert Nagy <[email protected]> Reviewed-By: Matteo Collina <[email protected]>

Author: ShogunPanda

doc/api/http.md

@@ -2364,8 +2364,28 @@ header name:
 `last-modified`, `location`, `max-forwards`, `proxy-authorization`, `referer`,
 `retry-after`, `server`, or `user-agent` are discarded.
 *`set-cookie` is always an array. Duplicates are added to the array.
-* For duplicate `cookie` headers, the values are joined together with ' '.
-* For all other headers, the values are joined together with ', '.
+* For duplicate `cookie` headers, the values are joined together with `; `.
+* For all other headers, the values are joined together with `, `.
+
+### `message.headersDistinct`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+*{Object}
+
+Similar to [`message.headers`][], but there is no join logic and the values are
+always arrays of strings, even for headers received just once.
+
+```js
+// Prints something like:
+//
+//{'user-agent': ['curl/7.22.0'],
+// host: ['127.0.0.1:8000'],
+// accept: ['*/*'] }
+console.log(request.headersDistinct);
+```
 
 ### `message.httpVersion`
 
@@ -2499,6 +2519,18 @@ added: v0.3.0
 
 The request/response trailers object. Only populated at the `'end'` event.
 
+### `message.trailersDistinct`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+*{Object}
+
+Similar to [`message.trailers`][], but there is no join logic and the values are
+always arrays of strings, even for headers received just once.
+Only populated at the `'end'` event.
+
 ### `message.url`
 
 <!-- YAML
@@ -2596,7 +2628,7 @@ Adds HTTP trailers (headers but at the end of the message) to the message.
 Trailers will **only** be emitted if the message is chunked encoded. If not,
 the trailers will be silently discarded.
 
-HTTP requires the `Trailer` header to be sent to emit trailers,
+HTTP requires the `Trailer` header to be sent to emit trailers,
 with a list of header field names in its value, e.g.
 
 ```js
@@ -2610,6 +2642,28 @@ message.end();
 Attempting to set a header field name or value that contains invalid characters
 will result in a `TypeError` being thrown.
 
+### `outgoingMessage.appendHeader(name, value)`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+*`name`{string} Header name
+*`value`{string|string\[]} Header value
+* Returns:{this}
+
+Append a single header value for the header object.
+
+If the value is an array, this is equivalent of calling this method multiple
+times.
+
+If there were no previous value for the header, this is equivalent of calling
+[`outgoingMessage.setHeader(name, value)`][].
+
+Depending of the value of `options.uniqueHeaders` when the client request or the
+server were created, this will end up in the header being sent multiple times or
+a single time with values joined using `; `.
+
 ### `outgoingMessage.connection`
 
 <!-- YAML
@@ -3026,6 +3080,9 @@ changes:
 *`keepAliveInitialDelay`{number} If set to a positive number, it sets the
  initial delay before the first keepalive probe is sent on an idle socket.
 **Default:**`0`.
+*`uniqueHeaders`{Array} A list of response headers that should be sent only
+ once. If the header's value is an array, the items will be joined
+ using `; `.
 
 *`requestListener`{Function}
 
@@ -3260,12 +3317,15 @@ changes:
 *`protocol`{string} Protocol to use. **Default:**`'http:'`.
 *`setHost`{boolean}: Specifies whether or not to automatically add the
 `Host` header. Defaults to `true`.
+*`signal`{AbortSignal}: An AbortSignal that may be used to abort an ongoing
+ request.
 *`socketPath`{string} Unix domain socket. Cannot be used if one of `host`
  or `port` is specified, as those specify a TCP Socket.
 *`timeout`{number}: A number specifying the socket timeout in milliseconds.
  This will set the timeout before the socket is connected.
-*`signal`{AbortSignal}: An AbortSignal that may be used to abort an ongoing
- request.
+*`uniqueHeaders`{Array} A list of request headers that should be sent
+ only once. If the header's value is an array, the items will be joined
+ using `; `.
 *`callback`{Function}
 * Returns:{http.ClientRequest}
 
@@ -3571,11 +3631,13 @@ try{
 [`http.request()`]: #httprequestoptions-callback
 [`message.headers`]: #messageheaders
 [`message.socket`]: #messagesocket
+[`message.trailers`]: #messagetrailers
 [`net.Server.close()`]: net.md#serverclosecallback
 [`net.Server`]: net.md#class-netserver
 [`net.Socket`]: net.md#class-netsocket
 [`net.createConnection()`]: net.md#netcreateconnectionoptions-connectlistener
 [`new URL()`]: url.md#new-urlinput-base
+[`outgoingMessage.setHeader(name, value)`]: #outgoingmessagesetheadername-value
 [`outgoingMessage.socket`]: #outgoingmessagesocket
 [`removeHeader(name)`]: #requestremoveheadername
 [`request.destroy()`]: #requestdestroyerror

lib/_http_client.js

@@ -52,7 +52,11 @@ const{
  isLenient,
  prepareError,
 }=require('_http_common');
-const{ OutgoingMessage }=require('_http_outgoing');
+const{
+ kUniqueHeaders,
+ parseUniqueHeadersOption,
+ OutgoingMessage
+}=require('_http_outgoing');
 constAgent=require('_http_agent');
 const{ Buffer }=require('buffer');
 const{ defaultTriggerAsyncIdScope }=require('internal/async_hooks');
@@ -300,6 +304,8 @@ function ClientRequest(input, options, cb){
 options.headers);
 }
 
+this[kUniqueHeaders]=parseUniqueHeadersOption(options.uniqueHeaders);
+
 letoptsWithoutSignal=options;
 if(optsWithoutSignal.signal){
 optsWithoutSignal=ObjectAssign({},options);

lib/_http_incoming.js

@@ -33,8 +33,10 @@ const{
 const{ Readable, finished }=require('stream');
 
 constkHeaders=Symbol('kHeaders');
+constkHeadersDistinct=Symbol('kHeadersDistinct');
 constkHeadersCount=Symbol('kHeadersCount');
 constkTrailers=Symbol('kTrailers');
+constkTrailersDistinct=Symbol('kTrailersDistinct');
 constkTrailersCount=Symbol('kTrailersCount');
 
 functionreadStart(socket){
@@ -123,6 +125,25 @@ ObjectDefineProperty(IncomingMessage.prototype, 'headers',{
 }
 });
 
+ObjectDefineProperty(IncomingMessage.prototype,'headersDistinct',{
+get: function(){
+if(!this[kHeadersDistinct]){
+this[kHeadersDistinct]={};
+
+constsrc=this.rawHeaders;
+constdst=this[kHeadersDistinct];
+
+for(letn=0;n<this[kHeadersCount];n+=2){
+this._addHeaderLineDistinct(src[n+0],src[n+1],dst);
+}
+}
+returnthis[kHeadersDistinct];
+},
+set: function(val){
+this[kHeadersDistinct]=val;
+}
+});
+
 ObjectDefineProperty(IncomingMessage.prototype,'trailers',{
 get: function(){
 if(!this[kTrailers]){
@@ -142,6 +163,25 @@ ObjectDefineProperty(IncomingMessage.prototype, 'trailers',{
 }
 });
 
+ObjectDefineProperty(IncomingMessage.prototype,'trailersDistinct',{
+get: function(){
+if(!this[kTrailersDistinct]){
+this[kTrailersDistinct]={};
+
+constsrc=this.rawTrailers;
+constdst=this[kTrailersDistinct];
+
+for(letn=0;n<this[kTrailersCount];n+=2){
+this._addHeaderLineDistinct(src[n+0],src[n+1],dst);
+}
+}
+returnthis[kTrailersDistinct];
+},
+set: function(val){
+this[kTrailersDistinct]=val;
+}
+});
+
 IncomingMessage.prototype.setTimeout=functionsetTimeout(msecs,callback){
 if(callback)
 this.on('timeout',callback);
@@ -361,6 +401,16 @@ function _addHeaderLine(field, value, dest){
 }
 }
 
+IncomingMessage.prototype._addHeaderLineDistinct=_addHeaderLineDistinct;
+function_addHeaderLineDistinct(field,value,dest){
+field=StringPrototypeToLowerCase(field);
+if(!dest[field]){
+dest[field]=[value];
+}else{
+dest[field].push(value);
+}
+}
+
 
 // Call this instead of resume() if we want to just
 // dump all the data to /dev/null

lib/_http_outgoing.js

@@ -34,6 +34,7 @@ const{
  ObjectPrototypeHasOwnProperty,
  ObjectSetPrototypeOf,
  RegExpPrototypeTest,
+ SafeSet,
  StringPrototypeToLowerCase,
  Symbol,
 }=primordials;
@@ -82,6 +83,7 @@ let debug = require('internal/util/debuglog').debuglog('http', (fn) =>{
 constHIGH_WATER_MARK=getDefaultHighWaterMark();
 
 constkCorked=Symbol('corked');
+constkUniqueHeaders=Symbol('kUniqueHeaders');
 
 constnop=()=>{};
 
@@ -502,7 +504,10 @@ function processHeader(self, state, key, value, validate){
 if(validate)
 validateHeaderName(key);
 if(ArrayIsArray(value)){
-if(value.length<2||!isCookieField(key)){
+if(
+(value.length<2||!isCookieField(key))&&
+(!self[kUniqueHeaders]||!self[kUniqueHeaders].has(StringPrototypeToLowerCase(key)))
+){
 // Retain for(;) loop for performance reasons
 // Refs: https://github.com/nodejs/node/pull/30958
 for(leti=0;i<value.length;i++)
@@ -571,6 +576,20 @@ const validateHeaderValue = hideStackFrames((name, value) =>{
 }
 });
 
+functionparseUniqueHeadersOption(headers){
+if(!ArrayIsArray(headers)){
+returnnull;
+}
+
+constunique=newSafeSet();
+constl=headers.length;
+for(leti=0;i<l;i++){
+unique.add(StringPrototypeToLowerCase(headers[i]));
+}
+
+returnunique;
+}
+
 OutgoingMessage.prototype.setHeader=functionsetHeader(name,value){
 if(this._header){
 thrownewERR_HTTP_HEADERS_SENT('set');
@@ -586,6 +605,36 @@ OutgoingMessage.prototype.setHeader = function setHeader(name, value){
 returnthis;
 };
 
+OutgoingMessage.prototype.appendHeader=functionappendHeader(name,value){
+if(this._header){
+thrownewERR_HTTP_HEADERS_SENT('append');
+}
+validateHeaderName(name);
+validateHeaderValue(name,value);
+
+constfield=StringPrototypeToLowerCase(name);
+constheaders=this[kOutHeaders];
+if(headers===null||!headers[field]){
+returnthis.setHeader(name,value);
+}
+
+// Prepare the field for appending, if required
+if(!ArrayIsArray(headers[field][1])){
+headers[field][1]=[headers[field][1]];
+}
+
+constexistingValues=headers[field][1];
+if(ArrayIsArray(value)){
+for(leti=0,length=value.length;i<length;i++){
+existingValues.push(value[i]);
+}
+}else{
+existingValues.push(value);
+}
+
+returnthis;
+};
+
 
 OutgoingMessage.prototype.getHeader=functiongetHeader(name){
 validateString(name,'name');
@@ -797,7 +846,6 @@ function connectionCorkNT(conn){
 conn.uncork();
 }
 
-
 OutgoingMessage.prototype.addTrailers=functionaddTrailers(headers){
 this._trailer='';
 constkeys=ObjectKeys(headers);
@@ -817,11 +865,31 @@ OutgoingMessage.prototype.addTrailers = function addTrailers(headers){
 if(typeoffield!=='string'||!field||!checkIsHttpToken(field)){
 thrownewERR_INVALID_HTTP_TOKEN('Trailer name',field);
 }
-if(checkInvalidHeaderChar(value)){
-debug('Trailer "%s" contains invalid characters',field);
-thrownewERR_INVALID_CHAR('trailer content',field);
+
+// Check if the field must be sent several times
+constisArrayValue=ArrayIsArray(value);
+if(
+isArrayValue&&value.length>1&&
+(!this[kUniqueHeaders]||!this[kUniqueHeaders].has(StringPrototypeToLowerCase(field)))
+){
+for(letj=0,l=value.length;j<l;j++){
+if(checkInvalidHeaderChar(value[j])){
+debug('Trailer "%s"[%d] contains invalid characters',field,j);
+thrownewERR_INVALID_CHAR('trailer content',field);
+}
+this._trailer+=field+': '+value[j]+'\r\n';
+}
+}else{
+if(isArrayValue){
+value=ArrayPrototypeJoin(value,' ');
+}
+
+if(checkInvalidHeaderChar(value)){
+debug('Trailer "%s" contains invalid characters',field);
+thrownewERR_INVALID_CHAR('trailer content',field);
+}
+this._trailer+=field+': '+value+'\r\n';
 }
-this._trailer+=field+': '+value+'\r\n';
 }
 };
 
@@ -997,6 +1065,8 @@ function(err, event){
 };
 
 module.exports={
+ kUniqueHeaders,
+ parseUniqueHeadersOption,
  validateHeaderName,
  validateHeaderValue,
  OutgoingMessage

lib/_http_server.js

@@ -47,7 +47,11 @@ const{
  prepareError,
 }=require('_http_common');
 const{ ConnectionsList }=internalBinding('http_parser');
-const{ OutgoingMessage }=require('_http_outgoing');
+const{
+ kUniqueHeaders,
+ parseUniqueHeadersOption,
+ OutgoingMessage
+}=require('_http_outgoing');
 const{
  kOutHeaders,
  kNeedDrain,
@@ -450,6 +454,7 @@ function Server(options, requestListener){
 this.maxHeadersCount=null;
 this.maxRequestsPerSocket=0;
 setupConnectionsTracking(this);
+this[kUniqueHeaders]=parseUniqueHeadersOption(options.uniqueHeaders);
 }
 ObjectSetPrototypeOf(Server.prototype,net.Server.prototype);
 ObjectSetPrototypeOf(Server,net.Server);
@@ -916,6 +921,7 @@ function parserOnIncoming(server, socket, state, req, keepAlive){
 socket,state);
 
 res.shouldKeepAlive=keepAlive;
+res[kUniqueHeaders]=server[kUniqueHeaders];
 DTRACE_HTTP_SERVER_REQUEST(req,socket);
 
 if(onRequestStartChannel.hasSubscribers){