Added Ability to turn template into a byte string

def.go

@@ -18,6 +18,7 @@ package gofpdf
 
 import (
 	"bytes"
+	"encoding/gob"
 	"io"
 	"time"
 )
@@ -175,6 +176,101 @@ type ImageInfoType struct {
 	dpi   float64
 }
 
+func (info *ImageInfoType) GobEncode() ([]byte, error) {
+	w := new(bytes.Buffer)
+	encoder := gob.NewEncoder(w)
+
+	err := encoder.Encode(info.data)
+	if err == nil {
+		err = encoder.Encode(info.smask)
+	}
+	if err == nil {
+		err = encoder.Encode(info.i)
+	}
+	if err == nil {
+		err = encoder.Encode(info.n)
+	}
+	if err == nil {
+		err = encoder.Encode(info.w)
+	}
+	if err == nil {
+		err = encoder.Encode(info.h)
+	}
+	if err == nil {
+		err = encoder.Encode(info.cs)
+	}
+	if err == nil {
+		err = encoder.Encode(info.pal)
+	}
+	if err == nil {
+		err = encoder.Encode(info.bpc)
+	}
+	if err == nil {
+		err = encoder.Encode(info.f)
+	}
+	if err == nil {
+		err = encoder.Encode(info.dp)
+	}
+	if err == nil {
+		err = encoder.Encode(info.trns)
+	}
+	if err == nil {
+		err = encoder.Encode(info.scale)
+	}
+	if err == nil {
+		err = encoder.Encode(info.dpi)
+	}
+
+	return w.Bytes(), err
+}
+
+func (info *ImageInfoType) GobDecode(buf []byte) error {
+	r := bytes.NewBuffer(buf)
+	decoder := gob.NewDecoder(r)
+
+	err := decoder.Decode(&info.data)
+	if err == nil {
+		err = decoder.Decode(&info.smask)
+	}
+	if err == nil {
+		err = decoder.Decode(&info.i)
+	}
+	if err == nil {
+		err = decoder.Decode(&info.n)
+	}
+	if err == nil {
+		err = decoder.Decode(&info.w)
+	}
+	if err == nil {
+		err = decoder.Decode(&info.h)
+	}
+	if err == nil {
+		err = decoder.Decode(&info.cs)
+	}
+	if err == nil {
+		err = decoder.Decode(&info.pal)
+	}
+	if err == nil {
+		err = decoder.Decode(&info.bpc)
+	}
+	if err == nil {
+		err = decoder.Decode(&info.f)
+	}
+	if err == nil {
+		err = decoder.Decode(&info.dp)
+	}
+	if err == nil {
+		err = decoder.Decode(&info.trns)
+	}
+	if err == nil {
+		err = decoder.Decode(&info.scale)
+	}
+	if err == nil {
+		err = decoder.Decode(&info.dpi)
+	}
+	return err
+}
+
 // PointConvert returns the value of pt, expressed in points (1/72 inch), as a
 // value expressed in the unit of measure specified in New(). Since font
 // management in Fpdf uses points, this method can help with line height

fpdf_test.go

@@ -19,6 +19,7 @@ package gofpdf_test
 import (
 	"bufio"
 	"bytes"
+	"encoding/gob"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -1950,10 +1951,23 @@ func ExampleFpdf_CreateTemplate() {
 	pdf.SetLineWidth(2.5)
 	pdf.SetFont("Arial", "B", 16)
 
+	template3 := new(gofpdf.FpdfTpl)
+	b := new(bytes.Buffer)
+	enc := gob.NewEncoder(b)
+
+	if err := enc.Encode(template); err != nil {
+		pdf.SetError(err)
+	}
+
+	dec := gob.NewDecoder(b)
+	if err := dec.Decode(template3); err != nil {
+		pdf.SetError(err)
+	}
+
 	pdf.AddPage()
-	pdf.UseTemplate(template)
-	pdf.UseTemplateScaled(template, gofpdf.PointType{X: 0, Y: 30}, tplSize)
-	pdf.UseTemplateScaled(template, gofpdf.PointType{X: 0, Y: 60}, tplSize.ScaleBy(1.4))
+	pdf.UseTemplate(template3)
+	pdf.UseTemplateScaled(template3, gofpdf.PointType{X: 0, Y: 30}, tplSize)
+	pdf.UseTemplateScaled(template3, gofpdf.PointType{X: 0, Y: 60}, tplSize.ScaleBy(1.4))
 	pdf.Line(40, 210, 60, 210)
 	pdf.Text(40, 200, "Template example page 1")
 

template.go

@@ -18,6 +18,7 @@ package gofpdf
  */
 
 import (
+	"encoding/gob"
 	"sort"
 )
 
@@ -107,6 +108,8 @@ type Template interface {
 	Bytes() []byte
 	Images() map[string]*ImageInfoType
 	Templates() []Template
+	gob.GobDecoder
+	gob.GobEncoder
 }
 
 func (f *Fpdf) templateFontCatalog() {

template_impl.go

@@ -1,5 +1,10 @@
 package gofpdf
 
+import (
+	"bytes"
+	"encoding/gob"
+)
+
 /*
  * Copyright (c) 2015 Kurt Jung (Gmail: kurt.w.jung),
  *   Marcus Downing, Jan Slabon (Setasign)
@@ -80,6 +85,60 @@ func (t *FpdfTpl) Templates() []Template {
 	return t.templates
 }
 
+func (t *FpdfTpl) GobEncode() ([]byte, error) {
+	w := new(bytes.Buffer)
+	encoder := gob.NewEncoder(w)
+
+	err := encoder.Encode(t.id)
+	if err == nil {
+		err = encoder.Encode(t.corner)
+	}
+	if err == nil {
+		err = encoder.Encode(t.size)
+	}
+	if err == nil {
+		err = encoder.Encode(t.bytes)
+	}
+	if err == nil {
+		err = encoder.Encode(t.images)
+	}
+	if err == nil {
+		err = encoder.Encode(t.templates)
+	}
+
+	return w.Bytes(), err
+}
+
+func (t *FpdfTpl) GobDecode(buf []byte) error {
+	r := bytes.NewBuffer(buf)
+	decoder := gob.NewDecoder(r)
+
+	err := decoder.Decode(&t.id)
+	if err == nil {
+		err = decoder.Decode(&t.corner)
+	}
+	if err == nil {
+		err = decoder.Decode(&t.size)
+	}
+	if err == nil {
+		err = decoder.Decode(&t.bytes)
+	}
+	if err == nil {
+		err = decoder.Decode(&t.images)
+	}
+	if err == nil {
+		templates := make([]*FpdfTpl, 0)
+		err = decoder.Decode(&templates)
+		t.templates = make([]Template, len(templates))
+
+		for x := 0; x < len(templates); x++ {
+			t.templates[x] = templates[x]
+		}
+	}
+
+	return err
+}
+
 // Tpl is an Fpdf used for writing a template. It has most of the facilities of
 // an Fpdf, but cannot add more pages. Tpl is used directly only during the
 // limited time a template is writable.