Fix websocket dial to ipv6 (#1454)

* fix ipv6 dial

* fly by pass the context to dial

internal/rpc/client_test.go

@@ -7,6 +7,7 @@ import (
 	"crypto/tls"
 	"crypto/x509"
 	"encoding/json"
+	"net"
 	"net/http"
 	"net/http/httptest"
 	"strings"
@@ -507,6 +508,27 @@ func newServer(f func(*websocket.Conn) error) *server {
 	return &srv
 }
 
+func newIPv6Server(f func(*websocket.Conn) error) *server {
+	var srv server
+	l, _ := net.Listen("tcp", "[::1]:0")
+	server := httptest.Server{
+		Listener: l,
+		Config:   &http.Server{Handler: handleWS(f)}, //nolint:gosec
+	}
+	server.StartTLS()
+	srv.Server = &server
+	srv.URL = "ws" + strings.TrimPrefix(srv.Server.URL, "http")
+	cp := x509.NewCertPool()
+	cp.AddCert(srv.Certificate())
+	srv.dialer = &rpc.Dialer{
+		TLSConfig: &tls.Config{
+			RootCAs:    cp,
+			MinVersion: tls.VersionTLS12,
+		},
+	}
+	return &srv
+}
+
 func handleWS(f func(*websocket.Conn) error) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
 		var u websocket.Upgrader

internal/rpc/dial _test.go

@@ -0,0 +1,66 @@
+// Copyright 2024 Canonical.
+
+package rpc_test
+
+import (
+	"context"
+	"encoding/pem"
+	"net/http"
+	"testing"
+
+	qt "github.com/frankban/quicktest"
+	"github.com/juju/juju/core/network"
+	jujuparams "github.com/juju/juju/rpc/params"
+	"github.com/juju/names/v5"
+
+	"github.com/canonical/jimm/v3/internal/dbmodel"
+	"github.com/canonical/jimm/v3/internal/rpc"
+)
+
+func TestDialIPv4(t *testing.T) {
+	c := qt.New(t)
+	ctx := context.Background()
+	fakeController := newServer(echo)
+	defer fakeController.Close()
+	controller := dbmodel.Controller{}
+	pemData := pem.EncodeToMemory(&pem.Block{
+		Type:  "CERTIFICATE",
+		Bytes: fakeController.Certificate().Raw,
+	})
+	controller.CACertificate = string(pemData)
+	hp, err := network.ParseMachineHostPort(fakeController.Listener.Addr().String())
+	c.Assert(err, qt.Equals, nil)
+	controller.Addresses = append(make([][]jujuparams.HostPort, 0), []jujuparams.HostPort{{
+		Address: jujuparams.Address{
+			Value: hp.Value,
+			Type:  "ipv4",
+		},
+		Port: hp.Port(),
+	}})
+	_, err = rpc.Dial(ctx, &controller, names.ModelTag{}, "", http.Header{})
+	c.Assert(err, qt.Equals, nil)
+}
+
+func TestDialIPv6(t *testing.T) {
+	c := qt.New(t)
+	ctx := context.Background()
+	fakeController := newIPv6Server(echo)
+	defer fakeController.Close()
+	controller := dbmodel.Controller{}
+	pemData := pem.EncodeToMemory(&pem.Block{
+		Type:  "CERTIFICATE",
+		Bytes: fakeController.Certificate().Raw,
+	})
+	controller.CACertificate = string(pemData)
+	hp, err := network.ParseMachineHostPort(fakeController.Listener.Addr().String())
+	c.Assert(err, qt.Equals, nil)
+	controller.Addresses = append(make([][]jujuparams.HostPort, 0), []jujuparams.HostPort{{
+		Address: jujuparams.Address{
+			Value: hp.Value,
+			Type:  "ipv6",
+		},
+		Port: hp.Port(),
+	}})
+	_, err = rpc.Dial(ctx, &controller, names.ModelTag{}, "", http.Header{})
+	c.Assert(err, qt.Equals, nil)
+}

internal/rpc/dial.go

@@ -45,7 +45,7 @@ func (d Dialer) DialWebsocket(ctx context.Context, url string, headers http.Head
 	dialer := websocket.Dialer{
 		TLSClientConfig: d.TLSConfig,
 	}
-	conn, resp, err := dialer.DialContext(context.Background(), url, headers)
+	conn, resp, err := dialer.DialContext(ctx, url, headers)
 	if err != nil {
 		zapctx.Error(ctx, "BasicDial failed", zap.Error(err))
 		return nil, errors.E(op, err)
@@ -89,7 +89,13 @@ func Dial(ctx context.Context, ctl *dbmodel.Controller, modelTag names.ModelTag,
 	for _, hps := range ctl.Addresses {
 		for _, hp := range hps {
 			if maybeReachable(hp.Scope) {
-				urls = append(urls, websocketURL(fmt.Sprintf("%s:%d", hp.Value, hp.Port), modelTag, finalPath))
+				var ip string
+				if hp.Type == string(network.IPv6Address) {
+					ip = fmt.Sprintf("[%s]:%d", hp.Value, hp.Port)
+				} else {
+					ip = fmt.Sprintf("%s:%d", hp.Value, hp.Port)
+				}
+				urls = append(urls, websocketURL(ip, modelTag, finalPath))
 			}
 		}
 	}