WIP use structured type

Still failing when joining;

    docker container ls --format 'table {{.ID}}\t{{join .IPAddresses ", "}}'
    CONTAINER ID   IP ADDRESSES
    245bd1d81375   bridge/172.17.0.2, foo/172.19.0.2

    docker container ls --format '{{json .IPAddresses}}'
    [{"Network":"bridge","IP":"172.17.0.2"},{"Network":"foo","IP":"172.19.0.2"}]

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cli/command/formatter/container.go

@@ -4,8 +4,10 @@
 package formatter
 
 import (
+	"cmp"
 	"fmt"
 	"net"
+	"slices"
 	"sort"
 	"strconv"
 	"strings"
@@ -40,6 +42,16 @@ func (p Platform) String() string {
 	return platforms.FormatAll(p.Platform)
 }
 
+// NetworkIP describes an IP-address and the network it's associated with.
+type NetworkIP struct {
+	Network string `json:"Network,omitempty"`
+	IP      string `json:"IP"`
+}
+
+func (p NetworkIP) String() string {
+	return p.Network + "/" + p.IP
+}
+
 // NewContainerFormat returns a Format for rendering using a Context
 func NewContainerFormat(source string, quiet bool, size bool) Format {
 	switch source {
@@ -340,19 +352,30 @@ func (c *ContainerContext) Networks() string {
 // IPAddresses returns the list of IP-addresses assigned to the container
 // IP-addresses are prefixed with the name of the network, separated with a colon.
 // For example: "bridge:192.168.1.10"
-func (c *ContainerContext) IPAddresses() []string {
+func (c *ContainerContext) IPAddresses() []NetworkIP {
-	ipAddresses := []string{}
+	if c.c.NetworkSettings == nil || len(c.c.NetworkSettings.Networks) == 0 {
-	if c.c.NetworkSettings == nil {
+		return []NetworkIP{}
-		return ipAddresses
 	}
+	ipAddresses := make([]NetworkIP, 0, len(c.c.NetworkSettings.Networks))
 	for name, nw := range c.c.NetworkSettings.Networks {
 		if nw.IPAddress != "" {
-			ipAddresses = append(ipAddresses, name+":"+nw.IPAddress)
+			ipAddresses = append(ipAddresses, NetworkIP{
+				Network: name,
+				IP:      nw.IPAddress,
+			})
 		}
 		if nw.GlobalIPv6Address != "" {
-			ipAddresses = append(ipAddresses, name+":"+nw.GlobalIPv6Address)
+			ipAddresses = append(ipAddresses, NetworkIP{
+				Network: name,
+				IP:      nw.GlobalIPv6Address,
+			})
 		}
 	}
+
+	slices.SortFunc(ipAddresses, func(a, b NetworkIP) int {
+		return cmp.Compare(a.String(), b.String())
+	})
+
 	return ipAddresses
 }
 

cli/command/formatter/container_test.go

@@ -439,7 +439,18 @@ func TestContainerContextWriteJSON(t *testing.T) {
 			Image:   "ubuntu",
 			Created: unix,
 			State:   container.StateRunning,
-
+			NetworkSettings: &container.NetworkSettingsSummary{
+				Networks: map[string]*network.EndpointSettings{
+					"bridge": {
+						IPAddress:         "172.17.0.1",
+						GlobalIPv6Address: "ff02::1",
+					},
+					"my-net": {
+						IPAddress:         "172.18.0.1",
+						GlobalIPv6Address: "ff02::2",
+					},
+				},
+			},
 			ImageManifestDescriptor: &ocispec.Descriptor{Platform: &ocispec.Platform{Architecture: "amd64", OS: "linux"}},
 		},
 		{
@@ -458,6 +469,7 @@ func TestContainerContextWriteJSON(t *testing.T) {
 			"Command":      `""`,
 			"CreatedAt":    expectedCreated,
 			"ID":           "containerID1",
+			"IPAddresses":  []any{},
 			"Image":        "ubuntu",
 			"Labels":       "",
 			"LocalVolumes": "0",
@@ -475,12 +487,18 @@ func TestContainerContextWriteJSON(t *testing.T) {
 			"Command":   `""`,
 			"CreatedAt": expectedCreated,
 			"ID":        "containerID2",
+			"IPAddresses": []any{
+				map[string]any{"IP": "172.17.0.1", "Network": "bridge"},
+				map[string]any{"IP": "ff02::1", "Network": "bridge"},
+				map[string]any{"IP": "172.18.0.1", "Network": "my-net"},
+				map[string]any{"IP": "ff02::2", "Network": "my-net"},
+			},
 			"Image":        "ubuntu",
 			"Labels":       "",
 			"LocalVolumes": "0",
 			"Mounts":       "",
 			"Names":        "foobar_bar",
-			"Networks":     "",
+			"Networks":     "bridge,my-net",
 			"Platform":     map[string]any{"architecture": "amd64", "os": "linux"},
 			"Ports":        "",
 			"RunningFor":   "About a minute ago",
@@ -492,6 +510,7 @@ func TestContainerContextWriteJSON(t *testing.T) {
 			"Command":      `""`,
 			"CreatedAt":    expectedCreated,
 			"ID":           "containerID3",
+			"IPAddresses":  []any{},
 			"Image":        "ubuntu",
 			"Labels":       "",
 			"LocalVolumes": "0",
@@ -564,8 +583,8 @@ func TestContainerContextIPAddresses(t *testing.T) {
 	out := bytes.NewBufferString("")
 	err := ContainerWrite(Context{Format: "{{.IPAddresses}}", Output: out}, containers)
 	assert.NilError(t, err)
-	assert.Equal(t, out.String(), `[one:192.168.1.2 two:192.168.178.2]
+	assert.Equal(t, out.String(), `[one/192.168.1.2 two/192.168.178.2]
-[one:192.168.1.3 two:192.168.178.3]
+[one/192.168.1.3 two/192.168.178.3]
 `)
 }
 

docs/reference/commandline/container_ls.md

@@ -455,6 +455,6 @@ Show the IP-addresses that containers have:
 $ docker ps --format "table {{.ID}}\\t{{join .IPAddresses \", \"}}"
 
 CONTAINER ID   IP ADDRESSES
-c0cf2877da71   bridge:172.17.0.3
+c0cf2877da71   bridge/172.17.0.3
-17e7d1910fc0   bridge:172.17.0.2, mynetwork:172.19.0.2
+17e7d1910fc0   bridge/172.17.0.2, mynetwork/172.19.0.2
 ```