feat: environment vars for extension service

This allows setting environment variables for the extension service.

Signed-off-by: Noel Georgi <[email protected]>

internal/app/machined/pkg/system/services/extension.go

@@ -115,6 +115,10 @@ func (svc *Extension) getOCIOptions() []oci.SpecOpts {
 		ociOpts = append(ociOpts, oci.WithWriteableSysfs)
 	}
 
+	if svc.Spec.Container.Environment != nil {
+		ociOpts = append(ociOpts, oci.WithEnv(svc.Spec.Container.Environment))
+	}
+
 	if svc.Spec.Container.Security.MaskedPaths != nil {
 		ociOpts = append(ociOpts, oci.WithMaskedPaths(svc.Spec.Container.Security.MaskedPaths))
 	}

internal/app/machined/pkg/system/services/extension_test.go

@@ -136,4 +136,24 @@ func TestGetOCIOptions(t *testing.T) {
 		assert.NoError(t, err)
 		assert.Equal(t, true, spec.Root.Readonly)
 	})
+
+	t.Run("allows setting extra env vars", func(t *testing.T) {
+		// given
+		svc := &services.Extension{
+			Spec: &extservices.Spec{
+				Container: extservices.Container{
+					Environment: []string{
+						"FOO=BAR",
+					},
+				},
+			},
+		}
+
+		// when
+		spec, err := generateOCISpec(svc)
+
+		// then
+		assert.NoError(t, err)
+		assert.Equal(t, []string{"FOO=BAR"}, spec.Process.Env)
+	})
 }

pkg/machinery/extensions/services/services.go

@@ -36,6 +36,8 @@ type Spec struct {
 type Container struct {
 	// Entrypoint for the service, relative to the container rootfs.
 	Entrypoint string `yaml:"entrypoint"`
+	// Environment variables for the service.
+	Environment []string `yaml:"environment"`
 	// Args to pass to the entrypoint.
 	Args []string `yaml:"args"`
 	// Volume mounts.

website/content/v1.3/advanced/extension-services.md

@@ -27,6 +27,8 @@ Format of the extension service config:
 name: hello-world
 container:
   entrypoint: ./hello-world
+  environment:
+    - XDG_RUNTIME_DIR=/run
   args:
      - -f
   mounts:
@@ -52,6 +54,7 @@ The extension service will be registered as a Talos service under an `ext-<name>
 ### `container`
 
 * `entrypoint` defines the container entrypoint relative to the container root filesystem (`/usr/local/lib/containers/<name>`)
+* `environment` defines the container environment variables
 * `args` defines the additional arguments to pass to the entrypoint
 * `mounts` defines the volumes to be mounted into the container root