vault namespaces: inject VAULT_NAMESPACE alongside VAULT_TOKEN + documentation

client/allocrunner/taskrunner/task_runner_getters.go

@@ -57,7 +57,7 @@ func (tr *TaskRunner) setVaultToken(token string) {
 	tr.vaultToken = token
 
 	// Update the task's environment
-	tr.envBuilder.SetVaultToken(token, tr.task.Vault.Env)
+	tr.envBuilder.SetVaultToken(token, tr.clientConfig.VaultConfig.Namespace, tr.task.Vault.Env)
 }
 
 // getDriverHandle returns a driver handle.

client/taskenv/env.go

@@ -85,6 +85,9 @@ const (
 
 	// VaultToken is the environment variable for passing the Vault token
 	VaultToken = "VAULT_TOKEN"
+
+	// VaultNamespace is the environment variable for passing the Vault namespace, if applicable
+	VaultNamespace = "VAULT_NAMESPACE"
 )
 
 // The node values that can be interpreted.
@@ -305,6 +308,7 @@ type Builder struct {
 	allocName        string
 	groupName        string
 	vaultToken       string
+	vaultNamespace   string
 	injectVaultToken bool
 	jobName          string
 
@@ -423,6 +427,11 @@ func (b *Builder) Build() *TaskEnv {
 		envMap[VaultToken] = b.vaultToken
 	}
 
+	// Build the Vault Namespace
+	if b.injectVaultToken && b.vaultNamespace != "" {
+		envMap[VaultNamespace] = b.vaultNamespace
+	}
+
 	// Copy task meta
 	for k, v := range b.taskMeta {
 		envMap[k] = v
@@ -753,9 +762,10 @@ func (b *Builder) SetTemplateEnv(m map[string]string) *Builder {
 	return b
 }
 
-func (b *Builder) SetVaultToken(token string, inject bool) *Builder {
+func (b *Builder) SetVaultToken(token, namespace string, inject bool) *Builder {
 	b.mu.Lock()
 	b.vaultToken = token
+	b.vaultNamespace = namespace
 	b.injectVaultToken = inject
 	b.mu.Unlock()
 	return b

client/taskenv/env_test.go

@@ -468,28 +468,59 @@ func TestEnvironment_VaultToken(t *testing.T) {
 	n := mock.Node()
 	a := mock.Alloc()
 	env := NewBuilder(n, a, a.Job.TaskGroups[0].Tasks[0], "global")
-	env.SetVaultToken("123", false)
+	env.SetVaultToken("123", "vault-namespace", false)
 
 	{
 		act := env.Build().All()
 		if act[VaultToken] != "" {
 			t.Fatalf("Unexpected environment variables: %s=%q", VaultToken, act[VaultToken])
 		}
+		if act[VaultNamespace] != "" {
+			t.Fatalf("Unexpected environment variables: %s=%q", VaultNamespace, act[VaultNamespace])
+		}
 	}
 
 	{
-		act := env.SetVaultToken("123", true).Build().List()
+		act := env.SetVaultToken("123", "", true).Build().List()
 		exp := "VAULT_TOKEN=123"
 		found := false
+		foundNs := false
 		for _, entry := range act {
 			if entry == exp {
 				found = true
-				break
+			}
+			if strings.HasPrefix(entry, "VAULT_NAMESPACE=") {
+				foundNs = true
 			}
 		}
 		if !found {
 			t.Fatalf("did not find %q in:\n%s", exp, strings.Join(act, "\n"))
 		}
+		if foundNs {
+			t.Fatalf("found unwanted VAULT_NAMESPACE in:\n%s", strings.Join(act, "\n"))
+		}
+	}
+
+	{
+		act := env.SetVaultToken("123", "vault-namespace", true).Build().List()
+		exp := "VAULT_TOKEN=123"
+		expNs := "VAULT_NAMESPACE=vault-namespace"
+		found := false
+		foundNs := false
+		for _, entry := range act {
+			if entry == exp {
+				found = true
+			}
+			if entry == expNs {
+				foundNs = true
+			}
+		}
+		if !found {
+			t.Fatalf("did not find %q in:\n%s", exp, strings.Join(act, "\n"))
+		}
+		if !foundNs {
+			t.Fatalf("did not find %q in:\n%s", expNs, strings.Join(act, "\n"))
+		}
 	}
 }
 

website/source/docs/job-specification/vault.html.md

@@ -47,8 +47,10 @@ job "docs" {
 ```
 
 The Nomad client will make the Vault token available to the task by writing it
-to the secret directory at `secrets/vault_token` and by injecting a VAULT_TOKEN
-environment variable.
+to the secret directory at `secrets/vault_token` and by injecting a `VAULT_TOKEN`
+environment variable. If the Nomad cluster is [configured](http://localhost:4567/docs/configuration/vault.html#namespace)
+to use [Vault Namespaces](https://www.vaultproject.io/docs/enterprise/namespaces/index.html), 
+a `VAULT_NAMESPACE` environment variable will be injected whenever `VAULT_TOKEN` is.
 
 If Nomad is unable to renew the Vault token (perhaps due to a Vault outage or
 network error), the client will attempt to retrieve a new Vault token. If successful, the
@@ -71,8 +73,8 @@ with Vault as well.
   string like `"SIGUSR1"` or `"SIGINT"`. This option is required if the
   `change_mode` is `signal`.
 
-- `env` `(bool: true)` - Specifies if the `VAULT_TOKEN` environment variable
-  should be set when starting the task.
+- `env` `(bool: true)` - Specifies if the `VAULT_TOKEN` and `VAULT_NAMESPACE`
+  environment variables should be set when starting the task.
 
 - `policies` `(array<string>: [])` - Specifies the set of Vault policies that
   the task requires. The Nomad client will retrieve a Vault token that is