1. The basic principles of Go Web framework
Before writing a web framework, we need to understand the basic principles of a web framework. Web frameworks usually include the following parts:
- HTTP Server: Used to listen for and process HTTP requests.
- routing: Match the corresponding processing function according to the requested URL.
- middleware: Perform some common operations during the request processing process, such as authentication, logging, etc.
- Template Engine: Used to render dynamic web pages.
2. Write a simple web framework
1. Create an HTTP server
Use Go languagenet/httpPackages can easily create an HTTP server. Here is a simple example:
package main
import (
"fmt"
"net/http"
)
func main() {
("/", hello)
(":8080", nil)
}
func hello(w , r *) {
(w, "Hello, World!")
}
In this example, we define ahelloFunctions are used as request processing functions and useBind it to the root URL (/). Then, throughStart the HTTP server and listen to port 8080.
2. Implement routing
To implement the routing function, we need to match the corresponding processing function according to the requested URL. Here is a simple routing implementation:
package main
import (
"fmt"
"net/http"
)
var routes = map[string]{
"/": hello,
"/about": about,
}
func main() {
("/", root)
(":8080", nil)
}
func root(w , r *) {
handler := routes[]
if handler != nil {
handler(w, r)
} else {
(w, r)
}
}
func hello(w , r *) {
(w, "Hello, World!")
}
func about(w , r *) {
(w, "About Us")
}
In this example, we define aroutesMap, map the URL path to the corresponding processing function. Then, inrootIn the function, we look up the corresponding processing function based on the requested URL path and execute it. If the corresponding processing function cannot be found, a 404 error is returned.
3. Add middleware
Middleware can perform some common operations during request processing. Here is a simple middleware example for logging the IP address of each request:
package main
import (
"fmt"
"net/http"
)
var routes = map[string]{
"/": hello,
"/about": about,
}
func main() {
("/", middleware(root))
(":8080", nil)
}
func middleware(next ) {
return func(w , r *) {
("IP Address: %s\n", )
next(w, r)
}
}
func root(w , r *) {
handler := routes[]
if handler != nil {
handler(w, r)
} else {
(w, r)
}
}
func hello(w , r *) {
(w, "Hello, World!")
}
func about(w , r *) {
(w, "About Us")
}
In this example, we define amiddlewarefunction, which takes a processing function as an argument and returns a new processing function. The new processing function will record the requested IP address before executing the original processing function. Then, inmainIn the function, we willrootFunctions are applied as middleware to all routes.
4. Use the template engine
To render dynamic web pages, we can use the template engine. Go language has many excellent template engines to choose from, such ashtml/template、text/templateandgohtml/templatewait.
This is the end of this article about writing a simple web framework in Go. For more information about writing a web framework in Go, please search for my previous articles or continue browsing the related articles below. I hope everyone will support me in the future!