Allow specification of the local network interface for HTTP requests. Fixes #1389.

source/vibe/core/driver.d

@@ -108,7 +108,7 @@ interface EventDriver {
 
 	/** Establiches a tcp connection on the specified host/port.
 	*/
-	TCPConnection connectTCP(NetworkAddress address);
+	TCPConnection connectTCP(NetworkAddress address, NetworkAddress bind_address);
 
 	/** Listens on the specified port and interface for TCP connections.
 

source/vibe/core/drivers/libasync.d

@@ -270,7 +270,7 @@ final class LibasyncDriver : EventDriver {
 
 	}
 
-	LibasyncTCPConnection connectTCP(NetworkAddress addr)
+	LibasyncTCPConnection connectTCP(NetworkAddress addr, NetworkAddress bind_addr)
 	{
 		AsyncTCPConnection conn = new AsyncTCPConnection(getEventLoop());
 
@@ -285,6 +285,8 @@ final class LibasyncDriver : EventDriver {
 			tcp_connection.acquireWriter();
 
 		tcp_connection.m_tcpImpl.conn = conn;
+		//conn.local = bind_addr;
+		conn.ip(bind_addr.toAddressString(), bind_addr.port);
 		conn.peer = addr;
 
 		enforce(conn.run(&tcp_connection.handler), "An error occured while starting a new connection: " ~ conn.error);

source/vibe/core/drivers/libevent2.d

@@ -281,22 +281,17 @@ final class Libevent2Driver : EventDriver {
 		return msg.addr;
 	}
 
-	Libevent2TCPConnection connectTCP(NetworkAddress addr)
+	Libevent2TCPConnection connectTCP(NetworkAddress addr, NetworkAddress bind_addr)
 	{
+		assert(addr.family == bind_addr.family, "Mismatching bind and target address.");
 
 		auto sockfd_raw = socket(addr.family, SOCK_STREAM, 0);
 		// on Win64 socket() returns a 64-bit value but libevent expects an int
 		static if (typeof(sockfd_raw).max > int.max) assert(sockfd_raw <= int.max || sockfd_raw == ~0);
 		auto sockfd = cast(int)sockfd_raw;
 		socketEnforce(sockfd != -1, "Failed to create socket.");
 
-		NetworkAddress bind_addr;
-		bind_addr.family = addr.family;
-		if (addr.family == AF_INET) bind_addr.sockAddrInet4.sin_addr.s_addr = 0;
-		else bind_addr.sockAddrInet6.sin6_addr.s6_addr[] = 0;
 		socketEnforce(bind(sockfd, bind_addr.sockAddr, bind_addr.sockAddrLen) == 0, "Failed to bind socket.");
-		socklen_t balen = bind_addr.sockAddrLen;
-		socketEnforce(getsockname(sockfd, bind_addr.sockAddr, &balen) == 0, "getsockname failed.");
 
 		if( evutil_make_socket_nonblocking(sockfd) )
 			throw new Exception("Failed to make socket non-blocking.");
@@ -333,6 +328,10 @@ final class Libevent2Driver : EventDriver {
 			throw new Exception(format("Failed to connect to %s: %s", addr.toString(), e.msg));
 		}
 
+		socklen_t balen = bind_addr.sockAddrLen;
+		socketEnforce(getsockname(sockfd, bind_addr.sockAddr, &balen) == 0, "getsockname failed.");
+		cctx.local_addr = bind_addr;
+
 		logTrace("Connect result status: %d", cctx.status);
 		enforce(cctx.status == BEV_EVENT_CONNECTED, format("Failed to connect to host %s: %s", addr.toString(), cctx.status));
 

source/vibe/core/drivers/win32.d

@@ -277,17 +277,13 @@ final class Win32EventDriver : EventDriver {
 		return addr;
 	}
 
-	Win32TCPConnection connectTCP(NetworkAddress addr)
+	Win32TCPConnection connectTCP(NetworkAddress addr, NetworkAddress bind_addr)
 	{
 		assert(m_tid == GetCurrentThreadId());
 
 		auto sock = WSASocketW(AF_INET, SOCK_STREAM, IPPROTO_TCP, null, 0, WSA_FLAG_OVERLAPPED);
 		socketEnforce(sock != INVALID_SOCKET, "Failed to create socket");
 
-		NetworkAddress bind_addr;
-		bind_addr.family = addr.family;
-		if (addr.family == AF_INET) bind_addr.sockAddrInet4.sin_addr.s_addr = 0;
-		else bind_addr.sockAddrInet6.sin6_addr.s6_addr[] = 0;
 		socketEnforce(bind(sock, bind_addr.sockAddr, bind_addr.sockAddrLen) == 0, "Failed to bind socket");
 
 		auto conn = new Win32TCPConnection(this, sock, addr);

source/vibe/core/net.d

@@ -88,15 +88,31 @@ TCPListener listenTCP_s(ushort port, void function(TCPConnection stream) connect
 /**
 	Establishes a connection to the given host/port.
 */
-TCPConnection connectTCP(string host, ushort port)
+TCPConnection connectTCP(string host, ushort port, string bind_interface = null, ushort bind_port = 0)
 {
 	NetworkAddress addr = resolveHost(host);
 	addr.port = port;
-	return connectTCP(addr);
+	NetworkAddress bind_address;
+	if (bind_interface.length) bind_address = resolveHost(bind_interface, addr.family);
+	else {
+		bind_address.family = addr.family;
+		if (addr.family == AF_INET) bind_address.sockAddrInet4.sin_addr.s_addr = 0;
+		else bind_address.sockAddrInet6.sin6_addr.s6_addr[] = 0;
+	}
+	bind_address.port = bind_port;
+	return getEventDriver().connectTCP(addr, bind_address);
 }
 /// ditto
-TCPConnection connectTCP(NetworkAddress addr) {
-	return getEventDriver().connectTCP(addr);
+TCPConnection connectTCP(NetworkAddress addr, NetworkAddress bind_address = anyAddress)
+{
+	if (bind_address.family == AF_UNSPEC) {
+		bind_address.family = addr.family;
+		if (addr.family == AF_INET) bind_address.sockAddrInet4.sin_addr.s_addr = 0;
+		else bind_address.sockAddrInet6.sin6_addr.s6_addr[] = 0;
+		bind_address.port = 0;
+	}
+	enforce(addr.family == bind_address.family, "Destination address and bind address have different address families.");
+	return getEventDriver().connectTCP(addr, bind_address);
 }
 
 
@@ -108,6 +124,13 @@ UDPConnection listenUDP(ushort port, string bind_address = "0.0.0.0")
 	return getEventDriver().listenUDP(port, bind_address);
 }
 
+NetworkAddress anyAddress()
+{
+	NetworkAddress ret;
+	ret.family = AF_UNSPEC;
+	return ret;
+}
+
 version(VibeLibasyncDriver) {
 	public import libasync.events : NetworkAddress;
 } else {

source/vibe/http/client.d

@@ -168,20 +168,23 @@ unittest {
 	usually requestHTTP should be used for making requests instead of manually using a
 	HTTPClient to do so.
 */
-auto connectHTTP(string host, ushort port = 0, bool use_tls = false, HTTPClientSettings settings = defaultSettings)
+auto connectHTTP(string host, ushort port = 0, bool use_tls = false, HTTPClientSettings settings = null)
 {
-	static struct ConnInfo { string host; ushort port; bool useTLS; string proxyIP; ushort proxyPort; }
+	static struct ConnInfo { string host; ushort port; bool useTLS; string proxyIP; ushort proxyPort; NetworkAddress bind_addr; }
 	static FixedRingBuffer!(Tuple!(ConnInfo, ConnectionPool!HTTPClient), 16) s_connections;
+
+	if (!settings) settings = defaultSettings;
+
 	if( port == 0 ) port = use_tls ? 443 : 80;
-	auto ckey = ConnInfo(host, port, use_tls, settings?settings.proxyURL.host:null, settings?settings.proxyURL.port:0);
+	auto ckey = ConnInfo(host, port, use_tls, settings.proxyURL.host, settings.proxyURL.port, settings.networkInterface);
 
 	ConnectionPool!HTTPClient pool;
 	foreach (c; s_connections)
-		if (c[0].host == host && c[0].port == port && c[0].useTLS == use_tls && ((c[0].proxyIP == settings.proxyURL.host && c[0].proxyPort == settings.proxyURL.port) || settings is null))
+		if (c[0] == ckey)
 			pool = c[1];
 
 	if (!pool) {
-		logDebug("Create HTTP client pool %s:%s %s proxy %s:%d", host, port, use_tls, ( settings ) ? settings.proxyURL.host : string.init, ( settings ) ? settings.proxyURL.port : 0);
+		logDebug("Create HTTP client pool %s:%s %s proxy %s:%d", host, port, use_tls, settings.proxyURL.host, settings.proxyURL.port);
 		pool = new ConnectionPool!HTTPClient({
 				auto ret = new HTTPClient;
 				ret.connect(host, port, use_tls, settings);
@@ -205,6 +208,9 @@ auto connectHTTP(string host, ushort port = 0, bool use_tls = false, HTTPClientS
 class HTTPClientSettings {
 	URL proxyURL;
 	Duration defaultKeepAliveTimeout = 10.seconds;
+
+	/// Forces a specific network interface to use for outgoing connections.
+	NetworkAddress networkInterface = anyAddress;
 }
 
 ///
@@ -524,10 +530,13 @@ final class HTTPClient {
 
 				NetworkAddress proxyAddr = resolveHost(m_settings.proxyURL.host, 0, use_dns);
 				proxyAddr.port = m_settings.proxyURL.port;
-				m_conn = connectTCP(proxyAddr);
+				m_conn = connectTCP(proxyAddr, m_settings.networkInterface);
+			}
+			else {
+				auto addr = resolveHost(m_server);
+				addr.port = m_port;
+				m_conn = connectTCP(addr, m_settings.networkInterface);
 			}
-			else
-				m_conn = connectTCP(m_server, m_port);
 
 			m_stream = m_conn;
 			if (m_tls) {

tests/vibe.http.client.1389/dub.json

@@ -0,0 +1,7 @@
+{
+	"name": "1389",
+	"dependencies": {
+		"vibe-d:http": { "path": "../../" }
+	},
+	"versions": ["VibeDefaultMain"]
+}

tests/vibe.http.client.1389/source/app.d

@@ -0,0 +1,42 @@
+import vibe.core.core;
+import vibe.core.log;
+import vibe.http.client;
+import vibe.http.server;
+import vibe.stream.operations : readAllUTF8;
+import std.exception : assertThrown;
+
+shared static this()
+{
+	// determine external network interface
+	auto ec = connectTCP("vibed.org", 80);
+	auto li = ec.localAddress;
+	ec.close();
+	li.port = 0;
+	logInfo("External interface: %s", li.toString());
+
+	auto settings = new HTTPServerSettings;
+	// 10k + issue number -> Avoid bind errors
+	settings.port = 11389;
+	settings.bindAddresses = [li.toAddressString()];
+	listenHTTP(settings, (req, res) {
+		if (req.clientAddress.toAddressString() == "127.0.0.1")
+			res.writeBody("local");
+		else res.writeBody("remote");
+	});
+
+	runTask({
+		scope(exit) exitEventLoop(true);
+
+		auto url = "http://"~li.toAddressString~":11389/";
+
+		auto cs = new HTTPClientSettings;
+		cs.networkInterface = resolveHost("127.0.0.1");
+		auto res = requestHTTP(url, null, cs).bodyReader.readAllUTF8();
+		assert(res == "local", "Unexpected reply: "~res);
+
+		auto cs2 = new HTTPClientSettings;
+		cs2.networkInterface = li;
+		res = requestHTTP(url, null, cs2).bodyReader.readAllUTF8();
+		assert(res == "remote", "Unexpected reply: "~res);
+    });
+}