Add dev flag to indicate development runs

Used to reload the templates on each page view.

lib/template.go

@@ -8,6 +8,7 @@ import (
 
 	"encoding/json"
 	"errors"
+	"io"
 	"net/http"
 	"path"
 	"strings"
@@ -53,9 +54,13 @@ func GetStatus(h handler) Status {
 	return s
 }
 
+type TemplateExecutor interface {
+	ExecuteTemplate(io.Writer, string, interface{}) error
+}
+
 type Template struct {
-	html *html_tmpl.Template
-	opds *txt_tmpl.Template
+	html TemplateExecutor
+	opds TemplateExecutor
 }
 
 func InitTemplate(assetsPath string) *Template {
@@ -78,6 +83,38 @@ func InitTemplate(assetsPath string) *Template {
 	return &t
 }
 
+type DevTemplateExecutor struct {
+	assetsPath string
+	tpe        string
+}
+
+func InitDevTemplate(assetsPath string) *Template {
+	return &Template{
+		html: DevTemplateExecutor{assetsPath, "html"},
+		opds: DevTemplateExecutor{assetsPath, "txt"},
+	}
+}
+
+func (e DevTemplateExecutor) ExecuteTemplate(wr io.Writer, name string, data interface{}) error {
+	templatePath := path.Join(e.assetsPath, "templates")
+	file := path.Join(templatePath, name)
+
+	var t TemplateExecutor
+	switch e.tpe {
+	case "html":
+		included_files := []string{file}
+		for _, f := range []string{"header.html", "footer.html", "book_list.html"} {
+			included_files = append(included_files, path.Join(templatePath, f))
+		}
+		t = html_tmpl.Must(html_tmpl.New("html").Funcs(html_tmpl.FuncMap{
+			"strings_join": strings.Join,
+		}).ParseFiles(included_files...))
+	case "txt":
+		t = txt_tmpl.Must(txt_tmpl.ParseFiles(file))
+	}
+	return t.ExecuteTemplate(wr, name, data)
+}
+
 func loadJson(w http.ResponseWriter, tmpl string, data interface{}) error {
 	var res []byte
 	var err error