How to get full server URL from any endpoint handler in Gin

Question

I'm creating an endpoint using Go's Gin web framework. I need full server URL in my handler function. For example, if server is running on http://localhost:8080 and my endpoint is /foo then I need http://localhost:8080/foo when my handler is called.

If anyone is familiar with Python's fast API, the Request object has a method url_for(<endpoint_name>) which has the exact same functionality: https://stackoverflow.com/a/63682957/5353128

In Go, I've tried accessing context.FullPath() but that only returns my endpoint /foo and not the full URL. Other than this, I can't find appropriate method in docs: https://pkg.go.dev/github.com/gin-gonic/gin#Context

So is this possible via gin.Context object itself or are there other ways as well? I'm completely new to Go.

Answer 1

c.Request.Host+c.Request.URL.Path should work but the scheme has to be determined.

package main

import (
    "fmt"

    "github.com/gin-gonic/gin"
)

func main() {
    r := gin.Default()

    r.GET("/foo", func(c *gin.Context) {
        fmt.Println("The URL: ", c.Request.Host+c.Request.URL.Path)
    })

    r.Run(":8080")
}

You can determine scheme which also you may know already. But you can check as follows:

scheme := "http"
if c.Request.TLS != nil {
    scheme = "https"
}

If your server is behind the proxy, you can get the scheme by c.Request.Header.Get("X-Forwarded-Proto")