feat: add groupipam networkservice server chain element

pkg/networkservice/ipam/groupipam/server.go

@@ -0,0 +1,67 @@
+// Copyright (c) 2023 Cisco and/or its affiliates.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at:
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package groupipam provides a networkservice.NetworkServiceServer chain element to handle a group of []*net.IPNet.
+// The chain element should be used when the endpoint should assign a few addresses for the connection.
+// By default `groupipam` uses `point2pointipam` to handle *net.IPNet.
+package groupipam
+
+import (
+	"net"
+
+	"github.com/networkservicemesh/api/pkg/api/networkservice"
+
+	"github.com/networkservicemesh/sdk/pkg/networkservice/core/chain"
+	"github.com/networkservicemesh/sdk/pkg/networkservice/ipam/point2pointipam"
+)
+
+type options struct {
+	newIPAMServerFn func(...*net.IPNet) networkservice.NetworkServiceServer
+}
+
+// Option allows to change a default behavior
+type Option func(*options)
+
+// WithCustomIPAMServer replaces default `point2pointipam` to custom implementation
+func WithCustomIPAMServer(f func(...*net.IPNet) networkservice.NetworkServiceServer) Option {
+	if f == nil {
+		panic("nil is not allowed")
+	}
+
+	return func(o *options) {
+		o.newIPAMServerFn = f
+	}
+}
+
+// NewServer creates a new instance of groupipam chain element that handles a group of []*net.IPNet.
+// Requires a group of []*net.IPNet.
+// Options can be passed optionally
+func NewServer(groups [][]*net.IPNet, opts ...Option) networkservice.NetworkServiceServer {
+	var ipamServers []networkservice.NetworkServiceServer
+	var o = options{
+		newIPAMServerFn: point2pointipam.NewServer,
+	}
+
+	for _, opt := range opts {
+		opt(&o)
+	}
+
+	for _, group := range groups {
+		ipamServers = append(ipamServers, o.newIPAMServerFn(group...))
+	}
+
+	return chain.NewNetworkServiceServer(ipamServers...)
+}

pkg/networkservice/ipam/groupipam/server_test.go

@@ -0,0 +1,128 @@
+// Copyright (c) 2023 Cisco and/or its affiliates.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at:
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package groupipam_test
+
+import (
+	"context"
+	"net"
+	"testing"
+
+	"github.com/networkservicemesh/api/pkg/api/networkservice"
+	"github.com/stretchr/testify/require"
+
+	"github.com/networkservicemesh/sdk/pkg/networkservice/common/updatepath"
+	"github.com/networkservicemesh/sdk/pkg/networkservice/core/chain"
+	"github.com/networkservicemesh/sdk/pkg/networkservice/ipam/groupipam"
+	"github.com/networkservicemesh/sdk/pkg/networkservice/ipam/singlepointipam"
+	"github.com/networkservicemesh/sdk/pkg/networkservice/utils/metadata"
+)
+
+func Test_NewServer_ShouldFailIfOptionIsNil(t *testing.T) {
+	require.Panics(t, func() {
+		groupipam.NewServer([][]*net.IPNet{}, groupipam.WithCustomIPAMServer(nil))
+	})
+}
+
+func Test_NewServer_UsesPoint2pointIPAMByDefault(t *testing.T) {
+	requireConns := func(t *testing.T, conn *networkservice.Connection, dsts, srcs []string) {
+		for i, dst := range dsts {
+			require.Equal(t, conn.Context.IpContext.DstIpAddrs[i], dst)
+			require.Equal(t, conn.Context.IpContext.SrcRoutes[i].Prefix, dst)
+		}
+		for i, src := range srcs {
+			require.Equal(t, conn.Context.IpContext.SrcIpAddrs[i], src)
+			require.Equal(t, conn.Context.IpContext.DstRoutes[i].Prefix, src)
+		}
+	}
+
+	_, ipNet1, err := net.ParseCIDR("172.92.3.4/16")
+	require.NoError(t, err)
+	_, ipNet2, err := net.ParseCIDR("fe80::/64")
+	require.NoError(t, err)
+
+	srv := groupipam.NewServer([][]*net.IPNet{{ipNet1}, {ipNet2}})
+
+	req := &networkservice.NetworkServiceRequest{
+		Connection: &networkservice.Connection{
+			Context: &networkservice.ConnectionContext{
+				IpContext: new(networkservice.IPContext),
+			},
+		},
+	}
+
+	req.Connection.Context.IpContext.ExcludedPrefixes = []string{"172.92.0.1/32", "fe80::1/128"}
+	conn, err := srv.Request(context.Background(), req.Clone())
+	require.NoError(t, err)
+	requireConns(t, conn, []string{"172.92.0.0/32", "fe80::/128"}, []string{"172.92.0.2/32", "fe80::2/128"})
+
+	req.Connection = conn
+	conn, err = srv.Request(context.Background(), req.Clone())
+	require.NoError(t, err)
+	requireConns(t, conn, []string{"172.92.0.0/32", "fe80::/128"}, []string{"172.92.0.2/32", "fe80::2/128"})
+
+	req.Connection = conn.Clone()
+	req.Connection.Context.IpContext.ExcludedPrefixes = []string{"172.92.0.1/30", "fe80::1/126"}
+	conn, err = srv.Request(context.Background(), req)
+	require.NoError(t, err)
+	requireConns(t, conn, []string{"172.92.0.4/32", "fe80::4/128"}, []string{"172.92.0.5/32", "fe80::5/128"})
+}
+
+func Test_NewServer_GroupOfCustomIPAMServers(t *testing.T) {
+	requireConns := func(t *testing.T, conn *networkservice.Connection, srcs []string) {
+		require.Equal(t, len(srcs), len(conn.Context.IpContext.SrcIpAddrs))
+		for i, src := range srcs {
+			require.Equal(t, src, conn.Context.IpContext.SrcIpAddrs[i])
+		}
+	}
+
+	_, ipNet1, err := net.ParseCIDR("172.92.3.4/16")
+	require.NoError(t, err)
+	_, ipNet2, err := net.ParseCIDR("fd00::/8")
+	require.NoError(t, err)
+
+	srv := chain.NewNetworkServiceServer(
+		updatepath.NewServer("ipam"),
+		metadata.NewServer(),
+		groupipam.NewServer([][]*net.IPNet{{ipNet1}, {ipNet2}}, groupipam.WithCustomIPAMServer(singlepointipam.NewServer)),
+	)
+	req := &networkservice.NetworkServiceRequest{
+		Connection: &networkservice.Connection{
+			Context: &networkservice.ConnectionContext{
+				IpContext: new(networkservice.IPContext),
+			},
+		},
+	}
+
+	conn1, err := srv.Request(context.Background(), req.Clone())
+	require.NoError(t, err)
+	requireConns(t, conn1, []string{"172.92.0.1/16", "fd00::1/8"})
+
+	conn2, err := srv.Request(context.Background(), req.Clone())
+	require.NoError(t, err)
+	requireConns(t, conn2, []string{"172.92.0.2/16", "fd00::2/8"})
+
+	_, err = srv.Close(context.Background(), conn1)
+	require.NoError(t, err)
+
+	conn3, err := srv.Request(context.Background(), req.Clone())
+	require.NoError(t, err)
+	requireConns(t, conn3, []string{"172.92.0.1/16", "fd00::1/8"})
+
+	conn4, err := srv.Request(context.Background(), req.Clone())
+	require.NoError(t, err)
+	requireConns(t, conn4, []string{"172.92.0.3/16", "fd00::3/8"})
+}