osbuild2: new org.osbuild.ostree.passwd stage

Add support for the `org.osbuild.ostree.passwd` and with it also
support for the `org.osbuild.ostree.checkout` input.
This stage can be used to pre-load the user and groups database
from an existing commit to ensure that uids/gids are stable.

internal/osbuild2/ostree_input.go

@@ -13,3 +13,30 @@ func NewOSTreeInput() *OSTreeInput {
 	input.Origin = "org.osbuild.source"
 	return input
 }
+
+// Inputs of type org.osbuild.ostree.checkout
+type OSTreeCheckoutInput struct {
+	inputCommon
+	References OSTreeCheckoutReferences `json:"references"`
+}
+
+func (OSTreeCheckoutInput) isStageInput() {}
+
+type OSTreeCheckoutReferences []string
+
+func (OSTreeCheckoutReferences) isReferences() {}
+
+// NewOSTreeCommitsInput creates a new OSTreeCommitsInputs
+// where `origin` is either "org.osbuild.source" or "org.osbuild.pipeline
+// `name` is the id of the commit, i.e. its digest or the pipeline name that
+// produced it)
+func NewOSTreeCheckoutInput(origin, name string) *OSTreeCheckoutInput {
+	input := new(OSTreeCheckoutInput)
+	input.Type = "org.osbuild.ostree.checkout"
+	input.Origin = origin
+
+	inputRefs := make([]string, 1)
+	inputRefs[0] = name
+	input.References = inputRefs
+	return input
+}

internal/osbuild2/ostree_passwd_stage.go

@@ -0,0 +1,21 @@
+package osbuild2
+
+// The org.osbuild.ostree.passwd stage has no options so far.
+type OSTreePasswdStageOptions struct {
+}
+
+func (s *OSTreePasswdStageOptions) isStageOptions() {}
+
+type OSTreePasswdStageInputs struct {
+	Commits *OSTreeCheckoutInput `json:"commits"`
+}
+
+func (OSTreePasswdStageInputs) isStageInputs() {}
+
+// A new org.osbuild.ostree.passwd stage to pre-fill the user and group databases
+func NewOSTreePasswdStage(origin, name string) *Stage {
+	return &Stage{
+		Type:   "org.osbuild.ostree.passwd",
+		Inputs: &OSTreePasswdStageInputs{Commits: NewOSTreeCheckoutInput(origin, name)},
+	}
+}

internal/osbuild2/stage.go

@@ -100,6 +100,9 @@ func (stage *Stage) UnmarshalJSON(data []byte) error {
 	case "org.osbuild.ostree.commit":
 		options = new(OSTreeCommitStageOptions)
 		inputs = new(OSTreeCommitStageInputs)
+	case "org.osbuild.ostree.passwd":
+		options = new(OSTreePasswdStageOptions)
+		inputs = new(OSTreePasswdStageInputs)
 	case "org.osbuild.ostree.pull":
 		options = new(OSTreePullStageOptions)
 		inputs = new(OSTreePullStageInputs)