Don’t crash when packaging YAML templates without transforms (closes #32

)

cmd/load_save.go

@@ -5,18 +5,25 @@ import (
 	"encoding/json"
 	"github.com/glassechidna/stackit/pkg/stackit"
 	"github.com/pkg/errors"
-	"gopkg.in/yaml.v2"
+	"gopkg.in/yaml.v3"
 	"io/ioutil"
+	"strings"
 )
 
 var DefaultOutputPath = "./stackit.packaged.yml"
 
 func savePreparedOutput(prepared *stackit.PrepareOutput) error {
+	jsonBody, err := ensureJson(prepared.TemplateBody)
+	if err != nil {
+		return errors.Wrap(err, "ensuring template is json")
+	}
+
 	prettyBuf := &bytes.Buffer{}
-	err := json.Indent(prettyBuf, []byte(prepared.TemplateBody), "", "  ")
+	err = json.Indent(prettyBuf, jsonBody, "", "  ")
 	if err != nil {
 		return errors.Wrap(err, "pretty-printing json of template body")
 	}
+
 	prepared.TemplateBody = prettyBuf.String()
 
 	marshalled, err := yaml.Marshal(prepared)
@@ -42,3 +49,49 @@ func loadPreparedOutput() (*stackit.PrepareOutput, error) {
 
 	return &output, nil
 }
+
+func ensureJson(input string) ([]byte, error) {
+	if strings.HasPrefix(input, "{") {
+		return []byte(input), nil
+	} else {
+		// we assume it's yaml
+		node := yaml.Node{}
+		err := yaml.Unmarshal([]byte(input), &node)
+		if err != nil {
+			return nil, errors.Wrap(err, "unmarshalling yaml into node")
+		}
+
+		return json.Marshal(jsonYamlNode(node))
+	}
+}
+
+type jsonYamlNode yaml.Node
+
+func (j jsonYamlNode) MarshalJSON() ([]byte, error) {
+	switch j.Kind {
+	case yaml.DocumentNode:
+		return json.Marshal(jsonYamlNode(*j.Content[0]))
+	case yaml.SequenceNode:
+		arr := []jsonYamlNode{}
+		for _, n := range j.Content {
+			arr = append(arr, jsonYamlNode(*n))
+		}
+		return json.Marshal(arr)
+	case yaml.MappingNode:
+		kv := map[string]jsonYamlNode{}
+		idx := 0
+		for idx < len(j.Content) {
+			keynode := j.Content[idx]
+			valnode := j.Content[idx+1]
+			kv[keynode.Value] = jsonYamlNode(*valnode)
+			idx += 2
+		}
+		return json.Marshal(kv)
+	case yaml.ScalarNode:
+		// TODO what about numerics?
+		return json.Marshal(j.Value)
+	case yaml.AliasNode:
+		panic("aliases not supported")
+	}
+	return nil, nil
+}

cmd/load_save_test.go

@@ -0,0 +1,20 @@
+package cmd
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestEnsureJson(t *testing.T) {
+	t.Run("input json", func(t *testing.T) {
+		output, err := ensureJson(`{"Hello": "world"}`)
+		assert.NoError(t, err)
+		assert.Equal(t, `{"Hello": "world"}`, string(output))
+	})
+
+	t.Run("input yaml", func(t *testing.T) {
+		output, err := ensureJson(`Hello: world`)
+		assert.NoError(t, err)
+		assert.Equal(t, `{"Hello":"world"}`, string(output))
+	})
+}

go.mod

@@ -23,4 +23,5 @@ require (
 	golang.org/x/sys v0.0.0-20181122145206-62eef0e2fa9b // indirect
 	gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
 	gopkg.in/yaml.v2 v2.2.1
+	gopkg.in/yaml.v3 v3.0.0-20190502103701-55513cacd4ae
 )

go.sum

@@ -71,3 +71,5 @@ gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.1 h1:mUhvW9EsL+naU5Q3cakzfE91YhliOondGd6ZrsDBHQE=
 gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v3 v3.0.0-20190502103701-55513cacd4ae h1:ehhBuCxzgQEGk38YjhFv/97fMIc2JGHZAhAWMmEjmu0=
+gopkg.in/yaml.v3 v3.0.0-20190502103701-55513cacd4ae/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=