Repository: lima-vm/lima (go)

Issue:
Embedded json templates are failing jsonschema validation
### Description

The files do not match the limayaml definition:

```go
type LimaYAML struct {
        Base                  BaseTemplates `yaml:"base,omitempty" json:"base,omitempty" jsonschema:"nullable"`
...
        Images                []Image       `yaml:"images" json:"images"` // REQUIRED
```

```go
type BaseTemplates []LocatorWithDigest

type LocatorWithDigest struct {
        URL    string  `yaml:"url" json:"url"`
        Digest *string `yaml:"digest,omitempty" json:"digest,omitempty" jsonschema:"nullable"` // TODO currently unused
}
```

There is no alternative, for string only (no wrapper)

```yaml
minimumLimaVersion: 1.1.0

base:
- template://_images/ubuntu-24.10
- template://_default/mounts
```

```
- at '': validation failed
  - at '': missing property 'images'
  - at '/base': oneOf failed, none matched
    - at '/base': validation failed
      - at '/base/0': got string, want object
      - at '/base/1': got string, want object
    - at '/base': got array, want null 
```

And it probably doesn't need to use "nullable" either?

```yaml
base: null
```

```yaml
- url: template://_images/default
  digest: null
```

It was mostly there for legacy (empty) yaml mappings.


Pull request:
Make the jsonschema validate the base
The images can now be null, since they can be embedded with base later on. Also allow strings for Templates and Locator.

There is no need to allow null values for the new fields, or to allow single items for the array in BaseTemplates.

Closes #3511

Patch:
diff --git a/Makefile b/Makefile
index 5f679955..c0b576d0 100644
--- a/Makefile
+++ b/Makefile
@@ -436,14 +436,15 @@ ifeq ($(native_compiling),true)
 	$< tmpl copy --embed-all templates/default.yaml $@
 endif
 
-schema-limayaml.json: _output/bin/limactl$(exe) default-template.yaml
+schema-limayaml.json: _output/bin/limactl$(exe) templates/default.yaml default-template.yaml
 ifeq ($(native_compiling),true)
-	$< generate-jsonschema --schemafile $@ default-template.yaml
+	# validate both the original template (with the "base" etc), and the embedded template
+	$< generate-jsonschema --schemafile $@ templates/default.yaml default-template.yaml
 endif
 
 .PHONY: check-jsonschema
-check-jsonschema: schema-limayaml.json default-template.yaml
-	check-jsonschema --schemafile schema-limayaml.json default-template.yaml
+check-jsonschema: schema-limayaml.json templates/default.yaml default-template.yaml
+	check-jsonschema --schemafile schema-limayaml.json templates/default.yaml default-template.yaml
 
 ################################################################################
 .PHONY: diagrams
diff --git a/cmd/limactl/genschema.go b/cmd/limactl/genschema.go
index 8de619fd..296db8ee 100644
--- a/cmd/limactl/genschema.go
+++ b/cmd/limactl/genschema.go
@@ -60,6 +60,18 @@ func genschemaAction(cmd *cobra.Command, args []string) error {
 		{Type: "string"},
 		{Type: "object"},
 	}
+	// allow BaseTemplates to be either string (url) or array (array)
+	schema.Definitions["BaseTemplates"].Type = "" // was: "array"
+	schema.Definitions["BaseTemplates"].OneOf = []*jsonschema.Schema{
+		{Type: "string"},
+		{Type: "array"},
+	}
+	// allow LocatorWithDigest to be either string (url) or object (struct)
+	schema.Definitions["LocatorWithDigest"].Type = "" // was: "object"
+	schema.Definitions["LocatorWithDigest"].OneOf = []*jsonschema.Schema{
+		{Type: "string"},
+		{Type: "object"},
+	}
 	properties := schema.Definitions["LimaYAML"].Properties
 	getProp(properties, "os").Enum = toAny(limayaml.OSTypes)
 	getProp(properties, "arch").Enum = toAny(limayaml.ArchTypes)
diff --git a/pkg/limayaml/limayaml.go b/pkg/limayaml/limayaml.go
index 4082b82d..d72e5b60 100644
--- a/pkg/limayaml/limayaml.go
+++ b/pkg/limayaml/limayaml.go
@@ -10,13 +10,13 @@ import (
 )
 
 type LimaYAML struct {
-	Base                  BaseTemplates `yaml:"base,omitempty" json:"base,omitempty" jsonschema:"nullable"`
+	Base                  BaseTemplates `yaml:"base,omitempty" json:"base,omitempty"`
 	MinimumLimaVersion    *string       `yaml:"minimumLimaVersion,omitempty" json:"minimumLimaVersion,omitempty" jsonschema:"nullable"`
 	VMType                *VMType       `yaml:"vmType,omitempty" json:"vmType,omitempty" jsonschema:"nullable"`
 	VMOpts                VMOpts        `yaml:"vmOpts,omitempty" json:"vmOpts,omitempty"`
 	OS                    *OS           `yaml:"os,omitempty" json:"os,omitempty" jsonschema:"nullable"`
 	Arch                  *Arch         `yaml:"arch,omitempty" json:"arch,omitempty" jsonschema:"nullable"`
-	Images                []Image       `yaml:"images" json:"images"` // REQUIRED
+	Images                []Image       `yaml:"images,omitempty" json:"images,omitempty" jsonschema:"nullable"`
 	CPUType               CPUType       `yaml:"cpuType,omitempty" json:"cpuType,omitempty" jsonschema:"nullable"`
 	CPUs                  *int          `yaml:"cpus,omitempty" json:"cpus,omitempty" jsonschema:"nullable"`
 	Memory                *string       `yaml:"memory,omitempty" json:"memory,omitempty" jsonschema:"nullable"` // go-units.RAMInBytes
@@ -58,7 +58,7 @@ type BaseTemplates []LocatorWithDigest
 
 type LocatorWithDigest struct {
 	URL    string  `yaml:"url" json:"url"`
-	Digest *string `yaml:"digest,omitempty" json:"digest,omitempty" jsonschema:"nullable"` // TODO currently unused
+	Digest *string `yaml:"digest,omitempty" json:"digest,omitempty"` // TODO currently unused
 }
 
 type (
@@ -229,7 +229,7 @@ const (
 type Provision struct {
 	Mode                            ProvisionMode      `yaml:"mode,omitempty" json:"mode,omitempty" jsonschema:"default=system"`
 	SkipDefaultDependencyResolution *bool              `yaml:"skipDefaultDependencyResolution,omitempty" json:"skipDefaultDependencyResolution,omitempty"`
-	Script                          string             `yaml:"script" json:"script"`
+	Script                          string             `yaml:"script,omitempty" json:"script,omitempty"`
 	File                            *LocatorWithDigest `yaml:"file,omitempty" json:"file,omitempty" jsonschema:"nullable"`
 	Playbook                        string             `yaml:"playbook,omitempty" json:"playbook,omitempty"` // DEPRECATED
 	// All ProvisionData fields must be nil unless Mode is ProvisionModeData
diff --git a/pkg/limayaml/marshal.go b/pkg/limayaml/marshal.go
index 0380fa9b..70caee2f 100644
--- a/pkg/limayaml/marshal.go
+++ b/pkg/limayaml/marshal.go
@@ -45,11 +45,6 @@ func unmarshalBaseTemplates(dst *BaseTemplates, b []byte) error {
 		*dst = BaseTemplates{LocatorWithDigest{URL: s}}
 		return nil
 	}
-	var locator LocatorWithDigest
-	if err := yaml.Unmarshal(b, &locator); err == nil {
-		*dst = BaseTemplates{locator}
-		return nil
-	}
 	return yaml.UnmarshalWithOptions(b, dst, yaml.CustomUnmarshaler[LocatorWithDigest](unmarshalLocatorWithDigest))
 }
 


Test patch:
diff --git a/pkg/limatmpl/abs_test.go b/pkg/limatmpl/abs_test.go
index b4f192f6..fbf7c19b 100644
--- a/pkg/limatmpl/abs_test.go
+++ b/pkg/limatmpl/abs_test.go
@@ -35,9 +35,9 @@ var useAbsLocatorsTestCases = []useAbsLocatorsTestCase{
 	{
 		"Flow style array of one base template",
 		"template://foo",
-		`base: {url: bar.yaml, digest: deadbeef}`,
+		`base: [{url: bar.yaml, digest: deadbeef}]`,
 		// not sure why the quotes around the URL were added; maybe because we don't copy the style from the source
-		`base: {url: 'template://bar.yaml', digest: deadbeef}`,
+		`base: [{url: 'template://bar.yaml', digest: deadbeef}]`,
 	},
 	{
 		"Flow style array of sequence of two base URLs",
diff --git a/pkg/limatmpl/embed_test.go b/pkg/limatmpl/embed_test.go
index a8e19291..e1db9ba2 100644
--- a/pkg/limatmpl/embed_test.go
+++ b/pkg/limatmpl/embed_test.go
@@ -374,13 +374,7 @@ provision:
 		`provision: [{script: "#! my script"}]`,
 	},
 	{
-		"ERROR base digest is not yet implemented (1)",
-		"",
-		"base: {url: base.yaml, digest: deafbad}",
-		"not yet implemented",
-	},
-	{
-		"ERROR base digest is not yet implemented (2)",
+		"ERROR base digest is not yet implemented",
 		"",
 		"base: [{url: base.yaml, digest: deafbad}]",
 		"not yet implemented",
diff --git a/pkg/limayaml/limayaml_test.go b/pkg/limayaml/limayaml_test.go
index a0320232..39c929ea 100644
--- a/pkg/limayaml/limayaml_test.go
+++ b/pkg/limayaml/limayaml_test.go
@@ -17,7 +17,7 @@ func dumpJSON(t *testing.T, d any) string {
 	return string(b)
 }
 
-const emptyYAML = "images: []\n"
+const emptyYAML = "{}\n"
 
 func TestEmptyYAML(t *testing.T) {
 	var y LimaYAML
@@ -27,7 +27,7 @@ func TestEmptyYAML(t *testing.T) {
 	assert.Equal(t, string(b), emptyYAML)
 }
 
-const defaultYAML = "images: []\n"
+const defaultYAML = "{}\n"
 
 func TestDefaultYAML(t *testing.T) {
 	bytes, err := os.ReadFile("default.yaml")
diff --git a/pkg/limayaml/marshal_test.go b/pkg/limayaml/marshal_test.go
index 29f2f72c..0f77b11f 100644
--- a/pkg/limayaml/marshal_test.go
+++ b/pkg/limayaml/marshal_test.go
@@ -28,7 +28,6 @@ func TestMarshalTilde(t *testing.T) {
 	// yaml will load ~ (or null) as null
 	// make sure that it is always quoted
 	assert.Equal(t, string(b), `---
-images: []
 mounts:
 - location: "~"
   writable: false