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// Copyright 2015 Canonical Ltd.
// Licensed under the LGPLv3, see LICENCE file for details.
package testing_test
import (
"fmt"
"io"
"net"
"sync"
"time"
"github.com/juju/testing"
gc "gopkg.in/check.v1"
)
var _ = gc.Suite(&tcpProxySuite{})
type tcpProxySuite struct{}
func (*tcpProxySuite) TestTCPProxy(c *gc.C) {
var wg sync.WaitGroup
listener, err := net.Listen("tcp", "127.0.0.1:0")
c.Assert(err, gc.IsNil)
defer listener.Close()
wg.Add(1)
go tcpEcho(&wg, listener)
p := testing.NewTCPProxy(c, listener.Addr().String())
c.Assert(p.Addr(), gc.Not(gc.Equals), listener.Addr().String())
// Dial the proxy and check that we see the text echoed correctly.
conn, err := net.Dial("tcp", p.Addr())
c.Assert(err, gc.IsNil)
defer conn.Close()
assertEcho(c, conn)
// Close the connection and check that we see
// the connection closed for read.
conn.(*net.TCPConn).CloseWrite()
assertEOF(c, conn)
// Make another connection and close the proxy,
// which should close down the proxy and cause us
// to get an error.
conn, err = net.Dial("tcp", p.Addr())
c.Assert(err, gc.IsNil)
defer conn.Close()
p.Close()
assertEOF(c, conn)
// Make sure that we cannot dial the proxy address either.
conn, err = net.Dial("tcp", p.Addr())
c.Assert(err, gc.ErrorMatches, ".*connection refused")
listener.Close()
// Make sure that all our connections have gone away too.
wg.Wait()
}
func (*tcpProxySuite) TestCloseConns(c *gc.C) {
var wg sync.WaitGroup
listener, err := net.Listen("tcp", "127.0.0.1:0")
c.Assert(err, gc.IsNil)
defer listener.Close()
wg.Add(1)
go tcpEcho(&wg, listener)
p := testing.NewTCPProxy(c, listener.Addr().String())
c.Assert(p.Addr(), gc.Not(gc.Equals), listener.Addr().String())
// Make a couple of connections through the proxy
// and test that they work.
conn1, err := net.Dial("tcp", p.Addr())
c.Assert(err, gc.IsNil)
defer conn1.Close()
assertEcho(c, conn1)
conn2, err := net.Dial("tcp", p.Addr())
c.Assert(err, gc.IsNil)
defer conn1.Close()
assertEcho(c, conn1)
p.CloseConns()
// Assert that both the connections have been broken.
assertEOF(c, conn1)
assertEOF(c, conn2)
// Check that we can still make a connection.
conn3, err := net.Dial("tcp", p.Addr())
c.Assert(err, gc.IsNil)
defer conn3.Close()
assertEcho(c, conn3)
// Close the proxy and check that the last connection goes.
p.Close()
assertEOF(c, conn3)
listener.Close()
// Make sure that all our connections have gone away too.
wg.Wait()
}
func (*tcpProxySuite) TestPauseConns(c *gc.C) {
var wg sync.WaitGroup
listener, err := net.Listen("tcp", "127.0.0.1:0")
c.Assert(err, gc.IsNil)
defer listener.Close()
wg.Add(1)
go tcpEcho(&wg, listener)
p := testing.NewTCPProxy(c, listener.Addr().String())
c.Assert(p.Addr(), gc.Not(gc.Equals), listener.Addr().String())
// Make a connection through the proxy
// and test that it works.
conn, err := net.Dial("tcp", p.Addr())
c.Assert(err, gc.IsNil)
defer conn.Close()
assertEcho(c, conn)
p.PauseConns()
msg := "hello, world\n"
n, err := fmt.Fprint(conn, msg)
c.Assert(err, gc.IsNil)
c.Assert(n, gc.Equals, len(msg))
assertReadTimeout(c, conn)
p.ResumeConns()
buf := make([]byte, n)
n, err = conn.Read(buf)
c.Assert(err, gc.IsNil)
c.Assert(n, gc.Equals, len(msg))
c.Assert(string(buf), gc.Equals, msg)
}
// tcpEcho listens on the given listener for TCP connections,
// writes all traffic received back to the sender, and calls
// wg.Done when all its goroutines have completed.
func tcpEcho(wg *sync.WaitGroup, listener net.Listener) {
defer wg.Done()
for {
conn, err := listener.Accept()
if err != nil {
return
}
wg.Add(1)
go func() {
defer wg.Done()
defer conn.Close()
// Echo anything that was written.
io.Copy(conn, conn)
}()
}
}
func assertEcho(c *gc.C, conn net.Conn) {
txt := "hello, world\n"
fmt.Fprint(conn, txt)
buf := make([]byte, len(txt))
n, err := io.ReadFull(conn, buf)
c.Assert(err, gc.IsNil)
c.Assert(string(buf[0:n]), gc.Equals, txt)
}
func assertEOF(c *gc.C, r io.Reader) {
n, err := r.Read(make([]byte, 1))
c.Assert(err, gc.Equals, io.EOF)
c.Assert(n, gc.Equals, 0)
}
func assertReadTimeout(c *gc.C, conn net.Conn) {
err := conn.SetReadDeadline(time.Now().Add(500 * time.Millisecond))
c.Assert(err, gc.IsNil)
defer conn.SetReadDeadline(time.Time{})
buf := make([]byte, 1)
n, err := conn.Read(buf)
c.Assert(n, gc.Equals, 0)
nerr, ok := err.(net.Error)
c.Assert(ok, gc.Equals, true)
c.Assert(nerr.Timeout(), gc.Equals, true)
}
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