From bcb9d77de04ee2a8a8bc23262dfb9b15b8efe0d5 Mon Sep 17 00:00:00 2001
From: Nikita Tokarchuk <nikita@tokarch.uk>
Date: Fri, 3 Dec 2021 02:50:31 +0100
Subject: [PATCH] Implement template writer helper

---
 frontend/renderer/output.go | 38 +++++++++++++++++++++++++++++++++++++
 go.mod                      |  1 +
 2 files changed, 39 insertions(+)
 create mode 100644 frontend/renderer/output.go

diff --git a/frontend/renderer/output.go b/frontend/renderer/output.go
new file mode 100644
index 0000000..d9caa33
--- /dev/null
+++ b/frontend/renderer/output.go
@@ -0,0 +1,38 @@
+package renderer
+
+import (
+	"io"
+
+	"code.tokarch.uk/mainnika/nikita-tokarch-uk/frontend/templates"
+	routing "github.com/jackwhelpton/fasthttp-routing/v2"
+	"github.com/valyala/fasthttp"
+)
+
+var _ routing.DataWriter = (*TemplateWriter)(nil)
+
+// staticWriter is thread-safe static instance of template writer
+var staticWriter = &TemplateWriter{}
+
+// TemplateWriter is the fasthttp data writer that loads and executes template using the content
+type TemplateWriter struct{}
+
+// SetHeader sets the content type to HTML since all templates are HTML
+func (tw *TemplateWriter) SetHeader(rh *fasthttp.ResponseHeader) {
+	rh.SetContentType(routing.MIME_HTML)
+}
+
+// Write executes the template and writes result to the response writer
+func (tw *TemplateWriter) Write(w io.Writer, content interface{}) error {
+
+	template := templates.GetTemplateOf(content)
+
+	return template.Execute(w, content)
+}
+
+// useTemplateWriter is the routing middleware to set the default data writer
+func (r *Renderer) useTemplateWriter(c *routing.Context) (err error) {
+
+	c.SetDataWriter(staticWriter)
+
+	return
+}
diff --git a/go.mod b/go.mod
index 84f71cf..aacb4ed 100644
--- a/go.mod
+++ b/go.mod
@@ -3,6 +3,7 @@ module code.tokarch.uk/mainnika/nikita-tokarch-uk
 go 1.17
 
 require (
+	github.com/jackwhelpton/fasthttp-routing/v2 v2.0.0
 	github.com/sirupsen/logrus v1.8.1
 	github.com/spf13/pflag v1.0.5
 	github.com/spf13/viper v1.9.0