Merge pull request #25 from technosophos/feat/toml-parser

feat(chart): add values parser

glide.lock

@@ -1,8 +1,10 @@
-hash: 7f9a27ad54a10edaa7c57521246676477d0f84ef4246524bae75f8df9d049983
-updated: 2016-04-14T12:24:49.130995956-06:00
+hash: e7c99013acb06eb359cf20390579af9a4553ef0fbed3f7bbb784b4ab7c8df807
+updated: 2016-04-15T15:15:21.87772545-06:00
 imports:
 - name: github.com/aokoli/goutils
   version: 9c37978a95bd5c709a15883b6242714ea6709e64
+- name: github.com/BurntSushi/toml
+  version: bbd5bb678321a0d6e58f1099321dfa73391c1b6f
 - name: github.com/codegangsta/cli
   version: 71f57d300dd6a780ac1856c005c4b518cfd498ec
 - name: github.com/golang/protobuf
@@ -28,7 +30,7 @@ imports:
   - http2/hpack
   - internal/timeseries
 - name: google.golang.org/grpc
-  version: 9ac074585f926c8506b6351bfdc396d2b19b1cb1
+  version: 8eeecf2291de9d171d0b1392a27ff3975679f4f5
   subpackages:
   - codes
   - credentials

glide.yaml

@@ -12,3 +12,4 @@ import:
 - package: gopkg.in/yaml.v2
 - package: github.com/Masterminds/semver
   version: 1.1.0
+- package: github.com/BurntSushi/toml

pkg/chart/testdata/coleridge.toml

@@ -0,0 +1,11 @@
+poet = "Coleridge"
+title = "Rime of the Ancient Mariner"
+stanza = ["at", "length", "did", "cross", "an", "Albatross"]
+
+[mariner]
+with = "crossbow"
+shot = "ALBATROSS"
+
+[water.water]
+where = "everywhere"
+nor = "any drop to drink"

pkg/chart/values.go

@@ -0,0 +1,67 @@
+package chart
+
+import (
+	"errors"
+	"io/ioutil"
+	"strings"
+
+	"github.com/BurntSushi/toml"
+)
+
+var ErrNoTable = errors.New("no table")
+
+type Values map[string]interface{}
+
+// Table gets a table (TOML subsection) from a Values object.
+//
+// The table is returned as a Values.
+//
+// Compound table names may be specified with dots:
+//
+//	foo.bar
+//
+// The above will be evaluated as "The table bar inside the table
+// foo".
+//
+// An ErrNoTable is returned if the table does not exist.
+func (v Values) Table(name string) (Values, error) {
+	names := strings.Split(name, ".")
+	table := v
+	var err error
+
+	for _, n := range names {
+		table, err = tableLookup(table, n)
+		if err != nil {
+			return table, err
+		}
+	}
+	return table, err
+}
+
+func tableLookup(v Values, simple string) (Values, error) {
+	v2, ok := v[simple]
+	if !ok {
+		return v, ErrNoTable
+	}
+	vv, ok := v2.(map[string]interface{})
+	if !ok {
+		return vv, ErrNoTable
+	}
+	return vv, nil
+}
+
+// ReadValues will parse TOML byte data into a Values.
+func ReadValues(data []byte) (Values, error) {
+	out := map[string]interface{}{}
+	err := toml.Unmarshal(data, out)
+	return out, err
+}
+
+// ReadValuesFile will parse a TOML file into a Values.
+func ReadValuesFile(filename string) (Values, error) {
+	data, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return map[string]interface{}{}, err
+	}
+	return ReadValues(data)
+}

pkg/chart/values_test.go

@@ -0,0 +1,134 @@
+package chart
+
+import (
+	"bytes"
+	"fmt"
+	"testing"
+	"text/template"
+)
+
+func TestReadValues(t *testing.T) {
+	doc := `# Test TOML parse
+poet = "Coleridge"
+title = "Rime of the Ancient Mariner"
+stanza = ["at", "length", "did", "cross", "an", "Albatross"]
+
+[mariner]
+with = "crossbow"
+shot = "ALBATROSS"
+
+[water.water]
+where = "everywhere"
+nor = "any drop to drink"
+`
+
+	data, err := ReadValues([]byte(doc))
+	if err != nil {
+		t.Fatalf("Error parsing bytes: %s", err)
+	}
+	matchValues(t, data)
+}
+
+func TestReadValuesFile(t *testing.T) {
+	data, err := ReadValuesFile("./testdata/coleridge.toml")
+	if err != nil {
+		t.Fatalf("Error reading TOML file: %s", err)
+	}
+	matchValues(t, data)
+}
+
+func ExampleValues() {
+	doc := `title="Moby Dick"
+[chapter.one]
+title = "Loomings"
+
+[chapter.two]
+title = "The Carpet-Bag"
+
+[chapter.three]
+title = "The Spouter Inn"
+`
+	d, err := ReadValues([]byte(doc))
+	if err != nil {
+		panic(err)
+	}
+	ch1, err := d.Table("chapter.one")
+	if err != nil {
+		panic("could not find chapter one")
+	}
+	fmt.Print(ch1["title"])
+	// Output:
+	// Loomings
+}
+
+func TestTable(t *testing.T) {
+	doc := `title="Moby Dick"
+[chapter.one]
+title = "Loomings"
+
+[chapter.two]
+title = "The Carpet-Bag"
+
+[chapter.three]
+title = "The Spouter Inn"
+`
+	d, err := ReadValues([]byte(doc))
+	if err != nil {
+		t.Fatalf("Failed to parse the White Whale: %s", err)
+	}
+
+	if _, err := d.Table("title"); err == nil {
+		t.Fatalf("Title is not a table.")
+	}
+
+	if _, err := d.Table("chapter"); err != nil {
+		t.Fatalf("Failed to get the chapter table: %s\n%v", err, d)
+	}
+
+	if v, err := d.Table("chapter.one"); err != nil {
+		t.Errorf("Failed to get chapter.one: %s", err)
+	} else if v["title"] != "Loomings" {
+		t.Errorf("Unexpected title: %s", v["title"])
+	}
+
+	if _, err := d.Table("chapter.three"); err != nil {
+		t.Errorf("Chapter three is missing: %s\n%v", err, d)
+	}
+
+	if _, err := d.Table("chapter.OneHundredThirtySix"); err == nil {
+		t.Errorf("I think you mean 'Epilogue'")
+	}
+}
+
+func matchValues(t *testing.T, data map[string]interface{}) {
+	if data["poet"] != "Coleridge" {
+		t.Errorf("Unexpected poet: %s", data["poet"])
+	}
+
+	if o, err := ttpl("{{len .stanza}}", data); err != nil {
+		t.Errorf("len stanza: %s", err)
+	} else if o != "6" {
+		t.Errorf("Expected 6, got %s", o)
+	}
+
+	if o, err := ttpl("{{.mariner.shot}}", data); err != nil {
+		t.Errorf(".mariner.shot: %s", err)
+	} else if o != "ALBATROSS" {
+		t.Errorf("Expected that mariner shot ALBATROSS")
+	}
+
+	if o, err := ttpl("{{.water.water.where}}", data); err != nil {
+		t.Errorf(".water.water.where: %s", err)
+	} else if o != "everywhere" {
+		t.Errorf("Expected water water everywhere")
+	}
+}
+
+func ttpl(tpl string, v map[string]interface{}) (string, error) {
+	var b bytes.Buffer
+	tt := template.Must(template.New("t").Parse(tpl))
+	if err := tt.Execute(&b, v); err != nil {
+		return "", err
+	}
+	return b.String(), nil
+}