Go by Example: HTTP Server

Go by Example : HTTP Server

Writing a basic HTTP server is easy using the `net/http`package.	`package main`
	`import ( "fmt" "net/http" )`
A fundamental concept in `net/http`servers is handlers . A handler is an object implementing the `http.Handler`interface. A common way to write a handler is by using the `http.HandlerFunc`adapter on functions with the appropriate signature.	`func hello(w http.ResponseWriter, req *http.Request) {`
Functions serving as handlers take a `http.ResponseWriter`and a `http.Request`as arguments. The response writer is used to fill in the HTTP response. Here our simple response is just “hello\n”.	`fmt.Fprintf(w, "hello\n") }`
	`func headers(w http.ResponseWriter, req *http.Request) {`
This handler does something a little more sophisticated by reading all the HTTP request headers and echoing them into the response body.	`for name, headers := range req.Header { for _, h := range headers { fmt.Fprintf(w, "%v: %v\n", name, h) } } }`
	`func main() {`
We register our handlers on server routes using the `http.HandleFunc`convenience function. It sets up the default router in the `net/http`package and takes a function as an argument.	`http.HandleFunc("/hello", hello) http.HandleFunc("/headers", headers)`
Finally, we call the `ListenAndServe`with the port and a handler. `nil`tells it to use the default router we’ve just set up.	`http.ListenAndServe(":8090", nil) }`

Run the server in the background.	`$ go run http-servers.go &`
Access the `/hello`route.	`$ curl localhost:8090/hello hello`

Next example: Context .