node pools: implement CLI (#17388)

command/node_pool_apply.go

@@ -0,0 +1,139 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package command
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+	"strings"
+
+	"github.com/hashicorp/hcl/v2/hclsimple"
+	"github.com/hashicorp/nomad/api"
+	"github.com/posener/complete"
+)
+
+type NodePoolApplyCommand struct {
+	Meta
+}
+
+func (c *NodePoolApplyCommand) Name() string {
+	return "node pool apply"
+}
+
+func (c *NodePoolApplyCommand) Synopsis() string {
+	return "Create or update a node pool"
+}
+
+func (c *NodePoolApplyCommand) Help() string {
+	helpText := `
+Usage: nomad node pool apply [options] <input>
+
+  Apply is used to create or update a node pool. The specification file is read
+  from stdin by specifying "-", otherwise a path to the file is expected.
+
+  If ACLs are enabled, this command requires a token with the 'write'
+  capability in a 'node_pool' policy that matches the node pool being targeted.
+
+General Options:
+
+  ` + generalOptionsUsage(usageOptsDefault) + `
+
+Apply Options:
+
+  -json
+    Parse the input as a JSON node pool specification.
+`
+	return strings.TrimSpace(helpText)
+}
+
+func (c *NodePoolApplyCommand) AutocompleteFlags() complete.Flags {
+	return mergeAutocompleteFlags(c.Meta.AutocompleteFlags(FlagSetClient),
+		complete.Flags{
+			"-json": complete.PredictNothing,
+		})
+}
+
+func (c *NodePoolApplyCommand) AutocompleteArgs() complete.Predictor {
+	return complete.PredictOr(
+		complete.PredictFiles("*.hcl"),
+		complete.PredictFiles("*.json"),
+	)
+}
+
+func (c *NodePoolApplyCommand) Run(args []string) int {
+	var jsonInput bool
+
+	flags := c.Meta.FlagSet(c.Name(), FlagSetClient)
+	flags.Usage = func() { c.Ui.Output(c.Help()) }
+	flags.BoolVar(&jsonInput, "json", false, "")
+
+	if err := flags.Parse(args); err != nil {
+		return 1
+	}
+
+	// Check that we only have one argument.
+	args = flags.Args()
+	if len(args) != 1 {
+		c.Ui.Error("This command takes one argument: <input>")
+		c.Ui.Error(commandErrorText(c))
+		return 1
+	}
+
+	// Read input content.
+	path := args[0]
+	var content []byte
+	var err error
+	switch path {
+	case "-":
+		content, err = io.ReadAll(os.Stdin)
+		if err != nil {
+			c.Ui.Error(fmt.Sprintf("Failed to read stdin: %v", err))
+			return 1
+		}
+		// Set .hcl extension so the decoder doesn't fail.
+		if !jsonInput {
+			path = "stdin.nomad.hcl"
+		}
+	default:
+		content, err = os.ReadFile(path)
+		if err != nil {
+			c.Ui.Error(fmt.Sprintf("Failed to read file %q: %v", path, err))
+			return 1
+		}
+	}
+
+	// Parse input.
+	var poolSpec nodePoolSpec
+	if jsonInput {
+		err = json.Unmarshal(content, &poolSpec.NodePool)
+	} else {
+		err = hclsimple.Decode(path, content, nil, &poolSpec)
+	}
+	if err != nil {
+		c.Ui.Error(fmt.Sprintf("Failed to parse input content: %v", err))
+		return 1
+	}
+
+	// Make API request.
+	client, err := c.Meta.Client()
+	if err != nil {
+		c.Ui.Error(fmt.Sprintf("Error initializing client: %s", err))
+		return 1
+	}
+
+	_, err = client.NodePools().Register(poolSpec.NodePool, nil)
+	if err != nil {
+		c.Ui.Error(fmt.Sprintf("Error applying node pool: %s", err))
+		return 1
+	}
+
+	c.Ui.Output(fmt.Sprintf("Successfully applied node pool %q!", poolSpec.NodePool.Name))
+	return 0
+}
+
+type nodePoolSpec struct {
+	NodePool *api.NodePool `hcl:"node_pool,block"`
+}