examples: add Word template example

Add an example that shows how to use a Word document
as a template and pull its styles for use in a new document.

_examples/document/use-template/main.go

@@ -0,0 +1,56 @@
+package main
+
+import (
+	"fmt"
+	"log"
+
+	"baliance.com/gooxml/document"
+)
+
+var lorem = `Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin lobortis, lectus dictum feugiat tempus, sem neque finibus enim, sed eleifend sem nunc ac diam. Vestibulum tempus sagittis elementum`
+
+func main() {
+	// When Word saves a document, it removes all unused styles.  This means to
+	// copy the styles from an existing document, you must first create a
+	// document that contains text in each style of interest.  As an example,
+	// see the template.docx in this directory.  It contains a paragraph set in
+	// each style that Word supports by default.
+	doc, err := document.OpenTemplate("template.docx")
+	if err != nil {
+		log.Fatalf("error opening Windows Word 2016 document: %s", err)
+	}
+
+	// We can now print out all styles in the document, verifying that they
+	// exist.
+	for _, s := range doc.Styles.ParagraphStyles() {
+		fmt.Println("style", s.Name(), "has ID of", s.StyleID())
+	}
+
+	// And create documents setting their style to the style ID (not style name).
+	para := doc.AddParagraph()
+	para.SetStyle("Title")
+	para.AddRun().AddText("My Document Title")
+
+	para = doc.AddParagraph()
+	para.SetStyle("Subtitle")
+	para.AddRun().AddText("Document Subtitle")
+
+	para = doc.AddParagraph()
+	para.SetStyle("Heading1")
+	para.AddRun().AddText("Major Section")
+	para = doc.AddParagraph()
+	para = doc.AddParagraph()
+	for i := 0; i < 4; i++ {
+		para.AddRun().AddText(lorem)
+	}
+
+	para = doc.AddParagraph()
+	para.SetStyle("Heading2")
+	para.AddRun().AddText("Minor Section")
+	para = doc.AddParagraph()
+	for i := 0; i < 4; i++ {
+		para.AddRun().AddText(lorem)
+	}
+
+	doc.SaveToFile("use-template.docx")
+}

document/document.go

@@ -272,6 +272,20 @@ func Open(filename string) (*Document, error) {
 	return Read(f, fi.Size())
 }
 
+// OpenTemplate opens a document, removing all content so it can be used as a
+// template.  Since Word removes unused styles from a document upon save, to
+// create a template in Word add a paragraph with every style of interest.  When
+// opened with OpenTemplate the documents styles will be available but the
+// content will be gone.
+func OpenTemplate(filename string) (*Document, error) {
+	d, err := Open(filename)
+	if err != nil {
+		return nil, err
+	}
+	d.x.Body = wml.NewCT_Body()
+	return d, nil
+}
+
 // Read reads a document from an io.Reader.
 func Read(r io.ReaderAt, size int64) (*Document, error) {
 	doc := New()

document/style.go

@@ -21,6 +21,11 @@ func (s Style) X() *wml.CT_Style {
 	return s.x
 }
 
+// Type returns the type of the style.
+func (s Style) Type() wml.ST_StyleType {
+	return s.x.TypeAttr
+}
+
 // StyleID returns the style ID.
 func (s Style) StyleID() string {
 	if s.x.StyleIdAttr == nil {

document/styles.go

@@ -206,3 +206,24 @@ func (s Styles) initializeDocDefaults() {
 	s.x.DocDefaults.PPrDefault.PPr.Spacing.LineAttr.Int32 = gooxml.Int32(259)
 	s.x.DocDefaults.PPrDefault.PPr.Spacing.LineRuleAttr = wml.ST_LineSpacingRuleAuto
 }
+
+// Styles returns all styles.
+func (s Styles) Styles() []Style {
+	ret := []Style{}
+	for _, s := range s.x.Style {
+		ret = append(ret, Style{s})
+	}
+	return ret
+}
+
+// Styles returns only paragraph styles.
+func (s Styles) ParagraphStyles() []Style {
+	ret := []Style{}
+	for _, s := range s.x.Style {
+		if s.TypeAttr != wml.ST_StyleTypeParagraph {
+			continue
+		}
+		ret = append(ret, Style{s})
+	}
+	return ret
+}

document/styles_test.go

@@ -0,0 +1,64 @@
+package document_test
+
+import (
+	"bytes"
+	"encoding/xml"
+	"fmt"
+	"os"
+	"testing"
+
+	"baliance.com/gooxml/document"
+	"baliance.com/gooxml/testhelper"
+	"baliance.com/gooxml/zippkg"
+)
+
+func TestStylesUnmarshal(t *testing.T) {
+	f, err := os.Open("testdata/styles.xml")
+	if err != nil {
+		t.Fatalf("error reading content types file")
+	}
+	defer f.Close()
+	dec := xml.NewDecoder(f)
+	r := document.NewStyles()
+	if err := dec.Decode(r.X()); err != nil {
+		t.Errorf("error decoding content types: %s", err)
+	}
+	got := &bytes.Buffer{}
+	fmt.Fprintf(got, zippkg.XMLHeader)
+	enc := xml.NewEncoder(zippkg.SelfClosingWriter{W: got})
+	if err := enc.Encode(r.X()); err != nil {
+		t.Errorf("error encoding content types: %s", err)
+	}
+
+	testhelper.CompareGoldenXML(t, "styles.xml", got.Bytes())
+}
+
+func TestStylesList(t *testing.T) {
+	f, err := os.Open("testdata/styles.xml")
+	if err != nil {
+		t.Fatalf("error reading content types file")
+	}
+	defer f.Close()
+	dec := xml.NewDecoder(f)
+	r := document.NewStyles()
+	if err := dec.Decode(r.X()); err != nil {
+		t.Errorf("error decoding content types: %s", err)
+	}
+	expStyleCnt := 26
+	if got := len(r.Styles()); got != expStyleCnt {
+		t.Errorf("expected %d total styles, got %d", expStyleCnt, got)
+	}
+
+	expParaStyleCnt := 9
+	if got := len(r.ParagraphStyles()); got != expParaStyleCnt {
+		t.Errorf("expected %d total paragraph styles, got %d", expStyleCnt, got)
+	}
+	for _, ps := range r.ParagraphStyles() {
+		switch ps.StyleID() {
+		case "Normal", "Heading1", "Heading2", "Heading3",
+			"Title", "Subtitle", "Quote", "IntenseQuote", "ListParagraph":
+		default:
+			t.Errorf("unexpected paragraph style: %s", ps.StyleID())
+		}
+	}
+}

spreadsheet/styles/stylesheet_test.go

@@ -19,7 +19,7 @@ import (
 	"baliance.com/gooxml/zippkg"
 )
 
-func TestWtyleSheetUnmarshal(t *testing.T) {
+func TestStyleSheetUnmarshal(t *testing.T) {
 	f, err := os.Open("testdata/styles.xml")
 	if err != nil {
 		t.Fatalf("error reading content types file")