add sample: appengine

samples/appengine/app.yaml

@@ -0,0 +1,8 @@
+application: draw2d-test
+version: 1
+runtime: go
+api_version: go1
+
+handlers:
+- url: /.*
+  script: _go_app

samples/appengine/server.go

@@ -0,0 +1,73 @@
+// +build appengine
+
+// Package gae demonstrates draw2d on a Google appengine server.
+package gae
+
+import (
+	"fmt"
+	"image"
+	"image/png"
+	"net/http"
+
+	"github.com/llgcode/draw2d"
+	"github.com/llgcode/draw2d/draw2dpdf"
+	"github.com/llgcode/draw2d/samples/android"
+
+	"appengine"
+)
+
+type appError struct {
+	Error   error
+	Message string
+	Code    int
+}
+
+type appHandler func(http.ResponseWriter, *http.Request) *appError
+
+func (fn appHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	if e := fn(w, r); e != nil { // e is *appError, not os.Error.
+		c := appengine.NewContext(r)
+		c.Errorf("%v", e.Error)
+		http.Error(w, e.Message, e.Code)
+	}
+}
+
+func init() {
+	http.Handle("/pdf", appHandler(pdf))
+	http.Handle("/png", appHandler(imgPng))
+}
+
+func pdf(w http.ResponseWriter, r *http.Request) *appError {
+	w.Header().Set("Content-type", "application/pdf")
+
+	// Initialize the graphic context on an pdf document
+	dest := draw2dpdf.NewPdf("L", "mm", "A4")
+	gc := draw2dpdf.NewGraphicContext(dest)
+
+	// Draw sample
+	android.Draw(gc, 65, 0)
+
+	err := dest.Output(w)
+	if err != nil {
+		return &appError{err, fmt.Sprintf("Can't write: %s", err), 500}
+	}
+	return nil
+}
+
+func imgPng(w http.ResponseWriter, r *http.Request) *appError {
+	w.Header().Set("Content-type", "image/png")
+
+	// Initialize the graphic context on an RGBA image
+	dest := image.NewRGBA(image.Rect(0, 0, 297, 210.0))
+	gc := draw2d.NewGraphicContext(dest)
+
+	// Draw sample
+	android.Draw(gc, 65, 0)
+
+	err := png.Encode(w, dest)
+	if err != nil {
+		return &appError{err, fmt.Sprintf("Can't encode: %s", err), 500}
+	}
+
+	return nil
+}