Templates

Rendering

Context#Render(code int, name string, data any) error renders a template with data and sends a text/html response with status code. Templates can be registered by setting Echo.Renderer, allowing us to use any template engine.

Example below shows how to use Go html/template:

Use default template renderer

e.Renderer =&echo.TemplateRenderer{
	Template: template.Must(template.New("hello").Parse("Hello, {{.}}!")),
}

or Implement echo.Renderer interface

type Template struct{
	templates *template.Template
}

func(t *Template)Render(c *echo.Context, w io.Writer, name string, data any)error{
return t.templates.ExecuteTemplate(w, name, data)
}

Pre-compile templates

public/views/hello.html

{{define "hello"}}Hello, {{.}}!{{end}}

t :=&Template{
 templates: template.Must(template.ParseGlob("public/views/*.html")),
}

e := echo.New()
e.Renderer = t
e.GET("/hello", Hello)

Render a template inside your handler

funcHello(c *echo.Context)error{
return c.Render(http.StatusOK,"hello","World")
}

Advanced - Calling Echo from templates

In certain situations it might be useful to generate URIs from the templates. In order to do so, you need to call Echo#Reverse from the templates itself. Golang's html/template package is not the best suited for this job, but this can be done in two ways: by providing a common method on all objects passed to templates or by passing map[string]any and augmenting this object in the custom renderer. Given the flexibility of the latter approach, here is a sample program:

template.html

<html>
<body>
<h1>Hello {{index . "name"}}</h1>

<p>{{ with $x := index . "reverse" }}
 {{ call $x "foobar" }} <!--- this will call the $x with parameter "foobar" -->
 {{ end }}
</p>
</body>
</html>

server.go

package main

import(
"html/template"
"io"
"net/http"

"github.com/labstack/echo/v5"
)

// TemplateRenderer is a custom html/template renderer for Echo framework
type TemplateRenderer struct{
	templates *template.Template
}

// Render renders a template document
func(t *TemplateRenderer)Render(c *echo.Context, w io.Writer, name string, data any)error{

// Add global methods if data is a map
if viewContext, isMap := data.(map[string]any); isMap {
		viewContext["reverse"]= c.RouteInfo().Reverse
}

return t.templates.ExecuteTemplate(w, name, data)
}

funcmain(){
	e := echo.New()
	e.Renderer =&TemplateRenderer{
		templates: template.Must(template.ParseGlob("main/*.html")),
}

	e.GET("/something/:name",func(c *echo.Context)error{
return c.Render(http.StatusOK,"template.html",map[string]any{
"name":"Dolly!",
})
})

if err := e.Start(":1323"); err !=nil{
		e.Logger.Error("shutting down the server","error", err)
}
}

Rendering​

Advanced - Calling Echo from templates​

Rendering

Advanced - Calling Echo from templates