Add hidden placeholder of `.Self` for `docker node ls --format`

This commit adds a hidden placeholder of `.Self` for
`docker node ls --format` so that if the node is the same
as the current docker daemon, then a `*` is outputed.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

cli/command/formatter/node.go

@@ -7,9 +7,10 @@ import (
 )
 
 const (
-	defaultNodeTableFormat = "table {{.ID}}\t{{.Hostname}}\t{{.Status}}\t{{.Availability}}\t{{.ManagerStatus}}"
+	defaultNodeTableFormat = "table {{.ID}} {{if .Self}}*{{else}} {{ end }}\t{{.Hostname}}\t{{.Status}}\t{{.Availability}}\t{{.ManagerStatus}}"
 
 	nodeIDHeader        = "ID"
+	selfHeader          = ""
 	hostnameHeader      = "HOSTNAME"
 	availabilityHeader  = "AVAILABILITY"
 	managerStatusHeader = "MANAGER STATUS"
@@ -46,6 +47,7 @@ func NodeWrite(ctx Context, nodes []swarm.Node, info types.Info) error {
 	nodeCtx := nodeContext{}
 	nodeCtx.header = nodeHeaderContext{
 		"ID":            nodeIDHeader,
+		"Self":          selfHeader,
 		"Hostname":      hostnameHeader,
 		"Status":        statusHeader,
 		"Availability":  availabilityHeader,
@@ -67,11 +69,11 @@ func (c *nodeContext) MarshalJSON() ([]byte, error) {
 }
 
 func (c *nodeContext) ID() string {
-	nodeID := c.n.ID
-	if nodeID == c.info.Swarm.NodeID {
-		nodeID = nodeID + " *"
-	}
-	return nodeID
+	return c.n.ID
+}
+
+func (c *nodeContext) Self() bool {
+	return c.n.ID == c.info.Swarm.NodeID
 }
 
 func (c *nodeContext) Hostname() string {

cli/command/formatter/node_test.go

@@ -148,8 +148,8 @@ func TestNodeContextWriteJSON(t *testing.T) {
 		{ID: "nodeID2", Description: swarm.NodeDescription{Hostname: "foobar_bar"}},
 	}
 	expectedJSONs := []map[string]interface{}{
-		{"Availability": "", "Hostname": "foobar_baz", "ID": "nodeID1", "ManagerStatus": "", "Status": ""},
-		{"Availability": "", "Hostname": "foobar_bar", "ID": "nodeID2", "ManagerStatus": "", "Status": ""},
+		{"Availability": "", "Hostname": "foobar_baz", "ID": "nodeID1", "ManagerStatus": "", "Status": "", "Self": false},
+		{"Availability": "", "Hostname": "foobar_bar", "ID": "nodeID2", "ManagerStatus": "", "Status": "", "Self": false},
 	}
 
 	out := bytes.NewBufferString("")

cli/command/node/list_test.go

@@ -129,7 +129,7 @@ func TestNodeListDefaultFormat(t *testing.T) {
 	})
 	cmd := newListCommand(cli)
 	assert.NilError(t, cmd.Execute())
-	assert.Contains(t, buf.String(), `nodeID1 *: nodeHostname1 Ready/Leader`)
+	assert.Contains(t, buf.String(), `nodeID1: nodeHostname1 Ready/Leader`)
 	assert.Contains(t, buf.String(), `nodeID2: nodeHostname2 Ready/Reachable`)
 	assert.Contains(t, buf.String(), `nodeID3: nodeHostname3 Ready`)
 }

docs/reference/commandline/cli.md

@@ -169,8 +169,8 @@ format. For a list of supported formatting directives, see
 
 The property `nodesFormat` specifies the default format for `docker node ls` output.
 When the `--format` flag is not provided with the `docker node ls` command,
-Docker's client uses this property. If this property is not set, the client
-falls back to the default table format. For a list of supported formatting
+Docker's client uses the value of `nodesFormat`. If the value of `nodesFormat` is not set,
+the client uses the default table format. For a list of supported formatting
 directives, see the [**Formatting** section in the `docker node ls` documentation](node_ls.md)
 
 The property `credsStore` specifies an external binary to serve as the default

docs/reference/commandline/node_ls.md

@@ -46,9 +46,10 @@ ID                           HOSTNAME        STATUS  AVAILABILITY  MANAGER STATU
 38ciaotwjuritcdtn9npbnkuz    swarm-worker1   Ready   Active
 e216jshn25ckzbvmwlnh5jr3g *  swarm-manager1  Ready   Active        Leader
 ```
-> **Note:**
-> If the `ID` field of the node is followed by a `*` (e.g., `e216jshn25ckzbvmwlnh5jr3g *`)
-> in the above example output, then this node is also the node of the current docker daemon.
+> **Note**:
+> In the above example output, there is a hidden column of `.Self` that indicates if the
+> node is the same node as the current docker daemon. A `*` (e.g., `e216jshn25ckzbvmwlnh5jr3g *`)
+> means this node is the current docker daemon.
 
 
 ### Filtering
@@ -139,6 +140,7 @@ Valid placeholders for the Go template are listed below:
 Placeholder      | Description
 -----------------|------------------------------------------------------------------------------------------
 `.ID`            | Node ID
+`.Self`          | Node of the daemon (`true/false`, `true`indicates that the node is the same as current docker daemon)
 `.Hostname`      | Node hostname
 `.Status`        | Node status
 `.Availability`  | Node availability ("active", "pause", or "drain")
@@ -153,7 +155,7 @@ The following example uses a template without headers and outputs the
 
 ```bash
 $ docker node ls --format "{{.ID}}: {{.Hostname}}"
-e216jshn25ckzbvmwlnh5jr3g *: swarm-manager1
+e216jshn25ckzbvmwlnh5jr3g: swarm-manager1
 ``