From 18f2ffaaa95077a0199a298a4c712b91293e7f01 Mon Sep 17 00:00:00 2001
From: William Petit <wpetit@cadoles.com>
Date: Fri, 24 Jan 2020 13:09:16 +0100
Subject: [PATCH] template: add layout loading API

---
 go.mod                    |  1 +
 template/html/provider.go |  2 +-
 template/html/service.go  | 54 +++++++++++++++++++++++++++++----------
 3 files changed, 43 insertions(+), 14 deletions(-)

diff --git a/go.mod b/go.mod
index 8cae12c..3eba97c 100644
--- a/go.mod
+++ b/go.mod
@@ -3,6 +3,7 @@ module gitlab.com/wpetit/goweb
 go 1.12
 
 require (
+	github.com/davecgh/go-spew v1.1.0
 	github.com/go-chi/chi v4.0.2+incompatible
 	github.com/go-playground/locales v0.12.1 // indirect
 	github.com/go-playground/universal-translator v0.16.0 // indirect
diff --git a/template/html/provider.go b/template/html/provider.go
index 1329fde..92263a3 100644
--- a/template/html/provider.go
+++ b/template/html/provider.go
@@ -6,7 +6,7 @@ import "gitlab.com/wpetit/goweb/service"
 // the HTML template service implementation
 func ServiceProvider(templateDir string, funcs ...OptionFunc) service.Provider {
 	templateService := NewTemplateService(funcs...)
-	err := templateService.LoadTemplates(templateDir)
+	err := templateService.LoadTemplatesDir(templateDir)
 	return func(container *service.Container) (interface{}, error) {
 		if err != nil {
 			return nil, err
diff --git a/template/html/service.go b/template/html/service.go
index 71b7211..cc05848 100644
--- a/template/html/service.go
+++ b/template/html/service.go
@@ -3,6 +3,7 @@ package html
 import (
 	"fmt"
 	"html/template"
+	"io/ioutil"
 	"net/http"
 	"path/filepath"
 
@@ -16,35 +17,62 @@ type TemplateService struct {
 	helpers   template.FuncMap
 }
 
-// LoadTemplates loads the templates used by the service
-func (t *TemplateService) LoadTemplates(templatesDir string) error {
+func (t *TemplateService) LoadLayout(name string, layout string, blocks []string) error {
+	tmpl := template.New(name)
+	tmpl.Funcs(t.helpers)
 
-	layouts, err := filepath.Glob(filepath.Join(templatesDir, "layouts", "*.tmpl"))
+	for _, b := range blocks {
+		if _, err := tmpl.Parse(b); err != nil {
+			return err
+		}
+	}
+
+	tmpl, err := tmpl.Parse(layout)
 	if err != nil {
 		return err
 	}
 
-	blocks, err := filepath.Glob(filepath.Join(templatesDir, "blocks", "*.tmpl"))
+	t.templates[name] = tmpl
+
+	return nil
+}
+
+// LoadTemplatesDir loads the templates used by the service
+func (t *TemplateService) LoadTemplatesDir(templatesDir string) error {
+
+	layoutFiles, err := filepath.Glob(filepath.Join(templatesDir, "layouts", "*.tmpl"))
 	if err != nil {
 		return err
 	}
 
-	// Generate our templates map from our layouts/ and blocks/ directories
-	for _, layout := range layouts {
+	blockFiles, err := filepath.Glob(filepath.Join(templatesDir, "blocks", "*.tmpl"))
+	if err != nil {
+		return err
+	}
 
-		var err error
-		files := append(blocks, layout)
+	blockTemplates := make([]string, 0, len(blockFiles))
 
-		tmpl := template.New("")
-		tmpl.Funcs(t.helpers)
-
-		tmpl, err = tmpl.ParseFiles(files...)
+	for _, f := range blockFiles {
+		templateData, err := ioutil.ReadFile(f)
 		if err != nil {
 			return err
 		}
 
-		t.templates[filepath.Base(layout)] = tmpl
+		blockTemplates = append(blockTemplates, string(templateData))
+	}
 
+	// Generate our templates map from our layouts/ and blocks/ directories
+	for _, f := range layoutFiles {
+		templateData, err := ioutil.ReadFile(f)
+		if err != nil {
+			return err
+		}
+
+		templateName := filepath.Base(f)
+
+		if err := t.LoadLayout(templateName, string(templateData), blockTemplates); err != nil {
+			return err
+		}
 	}
 
 	return nil