From 408a0edb172c73bdadd3caaefa90d529cab3a54c Mon Sep 17 00:00:00 2001
From: Jorge Marey <jorge.marey.oton.next@bbva.com>
Date: Sun, 27 Feb 2022 09:09:10 +0100
Subject: [PATCH] Add metadata to namespaces

---
 api/namespace.go                              |  1 +
 command/namespace_apply.go                    | 13 ++++++++++++
 command/namespace_status.go                   | 13 ++++++++++++
 nomad/structs/structs.go                      | 21 +++++++++++++++++++
 .../content/docs/commands/namespace/apply.mdx |  5 +++++
 5 files changed, 53 insertions(+)

diff --git a/api/namespace.go b/api/namespace.go
index 409a62bdd..7e5352126 100644
--- a/api/namespace.go
+++ b/api/namespace.go
@@ -71,6 +71,7 @@ type Namespace struct {
 	Description  string
 	Quota        string
 	Capabilities *NamespaceCapabilities `hcl:"capabilities,block"`
+	Meta         map[string]string
 	CreateIndex  uint64
 	ModifyIndex  uint64
 }
diff --git a/command/namespace_apply.go b/command/namespace_apply.go
index 118645963..edab6bff2 100644
--- a/command/namespace_apply.go
+++ b/command/namespace_apply.go
@@ -216,6 +216,7 @@ func parseNamespaceSpecImpl(result *api.Namespace, list *ast.ObjectList) error {
 	}
 
 	delete(m, "capabilities")
+	delete(m, "meta")
 
 	// Decode the rest
 	if err := mapstructure.WeakDecode(m, result); err != nil {
@@ -238,5 +239,17 @@ func parseNamespaceSpecImpl(result *api.Namespace, list *ast.ObjectList) error {
 		}
 	}
 
+	if metaO := list.Filter("meta"); len(metaO.Items) > 0 {
+		for _, o := range metaO.Elem().Items {
+			var m map[string]interface{}
+			if err := hcl.DecodeObject(&m, o.Val); err != nil {
+				return err
+			}
+			if err := mapstructure.WeakDecode(m, &result.Meta); err != nil {
+				return err
+			}
+		}
+	}
+
 	return nil
 }
diff --git a/command/namespace_status.go b/command/namespace_status.go
index 4f0f58b7f..654d1883d 100644
--- a/command/namespace_status.go
+++ b/command/namespace_status.go
@@ -2,6 +2,7 @@ package command
 
 import (
 	"fmt"
+	"sort"
 	"strings"
 
 	"github.com/hashicorp/nomad/api"
@@ -81,6 +82,18 @@ func (c *NamespaceStatusCommand) Run(args []string) int {
 
 	c.Ui.Output(formatNamespaceBasics(ns))
 
+	if len(ns.Meta) > 0 {
+		c.Ui.Output(c.Colorize().Color("\n[bold]Metadata[reset]"))
+		var keys []string
+		for k := range ns.Meta {
+			keys = append(keys, k)
+		}
+		sort.Strings(keys)
+		for _, k := range keys {
+			c.Ui.Output(fmt.Sprintf("%s:\x1f%s", k, ns.Meta[k]))
+		}
+	}
+
 	if ns.Quota != "" {
 		quotas := client.Quotas()
 		spec, _, err := quotas.Info(ns.Quota, nil)
diff --git a/nomad/structs/structs.go b/nomad/structs/structs.go
index 9a30381cf..78082eb44 100644
--- a/nomad/structs/structs.go
+++ b/nomad/structs/structs.go
@@ -4963,6 +4963,9 @@ type Namespace struct {
 	// Capabilities is the set of capabilities allowed for this namespace
 	Capabilities *NamespaceCapabilities
 
+	// Meta is the set of metadata key/value pairs that attached to the namespace
+	Meta map[string]string
+
 	// Hash is the hash of the namespace which is used to efficiently replicate
 	// cross-regions.
 	Hash []byte
@@ -5016,6 +5019,18 @@ func (n *Namespace) SetHash() []byte {
 		}
 	}
 
+	// sort keys to ensure hash stability when meta is stored later
+	var keys []string
+	for k := range n.Meta {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+
+	for _, k := range keys {
+		_, _ = hash.Write([]byte(k))
+		_, _ = hash.Write([]byte(n.Meta[k]))
+	}
+
 	// Finalize the hash
 	hashVal := hash.Sum(nil)
 
@@ -5035,6 +5050,12 @@ func (n *Namespace) Copy() *Namespace {
 		c.DisabledTaskDrivers = helper.CopySliceString(n.Capabilities.DisabledTaskDrivers)
 		nc.Capabilities = c
 	}
+	if n.Meta != nil {
+		nc.Meta = make(map[string]string, len(n.Meta))
+		for k, v := range n.Meta {
+			nc.Meta[k] = v
+		}
+	}
 	copy(nc.Hash, n.Hash)
 	return nc
 }
diff --git a/website/content/docs/commands/namespace/apply.mdx b/website/content/docs/commands/namespace/apply.mdx
index d9f93453c..fa54517c2 100644
--- a/website/content/docs/commands/namespace/apply.mdx
+++ b/website/content/docs/commands/namespace/apply.mdx
@@ -64,5 +64,10 @@ capabilities {
   enabled_task_drivers  = ["docker", "exec"]
   disabled_task_drivers = ["raw_exec"]
 }
+
+meta {
+  owner = "John Doe"
+  contact_mail = "john@mycompany.com
+}
 $ nomad namespace apply namespace.json
 ```