feat: allow to bind to multiple host IP addresses specified as CIDR prefix in x-ports (#358)

Signed-off-by: Miek Gieben <miek@miek.nl>
Co-authored-by: Pasha Sviderski <me@psviderski.name>

pkg/client/compose/port.go

@@ -112,10 +112,14 @@ func convertServicePortConfigToPortSpec(port types.ServicePortConfig) (api.PortS
 	// Set host IP if specified
 	if port.HostIP != "" {
 		hostIP, err := netip.ParseAddr(port.HostIP)
-		if err != nil {
-			return spec, fmt.Errorf("invalid host IP %q: %w", port.HostIP, err)
+		if err == nil {
+			spec.HostIP = hostIP
+		} else {
+			spec.HostPrefix, err = netip.ParsePrefix(port.HostIP)
+			if err != nil {
+				return spec, fmt.Errorf("invalid host IP or prefix '%s': %w", port.HostIP, err)
+			}
 		}
-		spec.HostIP = hostIP
 	}
 
 	// Validate the resulting spec

pkg/client/compose/port_test.go

@@ -58,6 +58,15 @@ func TestConvertStandardPortsToPortSpecs(t *testing.T) {
 				{ContainerPort: 8080, PublishedPort: 80, Protocol: "tcp", Mode: "host", HostIP: mustParseAddr("::1")},
 			},
 		},
+		{
+			name: "host prefix",
+			ports: []types.ServicePortConfig{
+				{Target: 8080, Published: "80", Protocol: "tcp", HostIP: "192.168.76.0/24", Mode: "host"},
+			},
+			expected: []api.PortSpec{
+				{ContainerPort: 8080, PublishedPort: 80, Protocol: "tcp", Mode: "host", HostPrefix: netip.MustParsePrefix("192.168.76.0/24")},
+			},
+		},
 	}
 
 	for _, tt := range tests {

pkg/client/compose/service_test.go

@@ -315,7 +315,7 @@ func TestServiceSpecFromCompose(t *testing.T) {
 					return strings.Compare(a.Name, b.Name)
 				})
 
-				cmpOpts := cmp.Options{cmpopts.EquateEmpty(), cmpopts.EquateComparable(netip.Addr{})}
+				cmpOpts := cmp.Options{cmpopts.EquateEmpty(), cmpopts.EquateComparable(netip.Addr{}, netip.Prefix{})}
 				assert.True(t, cmp.Equal(spec, expectedSpec, cmpOpts...), cmp.Diff(spec, expectedSpec, cmpOpts...))
 			}
 		})