Differences

This shows you the differences between two versions of the page.

--- go:stdlib:http_server [2025/12/29 23:29] – phong2018
+++ go:stdlib:http_server [2025/12/29 23:33] (current) – phong2018
@@ Line 1: / Line 1: @@
-===== HTTP Server =====
+===== HTTP Server (net/http) =====
 ==== What is it? ====
 An **HTTP server** is a program (service) that:
-  * **listens** on a network address (host:port), and
+  * **listens** on an address (host:port),
-  * **handles** incoming HTTP requests, then
+  * accepts incoming HTTP connections/requests,
-  * sends back HTTP responses.
+  * runs a **handler** to process each request,
+  * writes an HTTP response (status + headers + body).
-In Go, you commonly build HTTP servers using the standard library package `net/http`.
+In Go, the standard library package `net/http` provides everything needed to build an HTTP server.
 ==== What is it used for? ====
-  * Build web APIs (REST) and microservices.
+  * Build REST APIs and microservices.
-  * Serve web pages, JSON, files.
+  * Serve web pages, JSON, files, webhooks.
-  * Provide health checks (e.g. `/health`) for monitoring and load balancers.
+  * Provide health checks (e.g. `/health`) for monitoring/load balancers.
-==== How it works (simple flow) ====
+==== Core building blocks ====
-  - Client (browser/app) sends an HTTP request (example: `GET /health`)
+  * **Handler**: processes requests and writes responses
-  - Server receives the request
+    * `http.Handler` (interface)
-  - Server calls a **handler**
+    * `http.HandlerFunc` (function adapter)
-  - Handler writes an HTTP response (status code + headers + body)
+  * **ResponseWriter**: writes status code, headers, and body.
+  * **Request**: method, URL, headers, body, context.
+  * **ServeMux (router)**: maps URL paths to handlers
+    * `http.DefaultServeMux` is the default global mux.
+    * `http.NewServeMux()` creates a dedicated mux.
-==== Minimal example (Go net/http) ====
+==== Minimal server (custom mux) ====
 <code go>
 package main
-import "net/http"
+import (
+    "log"
+    "net/http"
+)
 func main() {
-    http.HandleFunc("/health", func(w http.ResponseWriter, r *http.Request) {
+    mux := http.NewServeMux()
+    mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+        w.Write([]byte("hello"))
+    })
+    mux.HandleFunc("/health", func(w http.ResponseWriter, r *http.Request) {
         w.WriteHeader(http.StatusOK)
         w.Write([]byte("ok"))
     })
-    http.ListenAndServe(":8080", nil)
+    log.Println("listening on :8080")
+    log.Fatal(http.ListenAndServe(":8080", mux))
 }
 </code>
-==== Key concepts ====
+==== Common patterns ====
-  * **Handler**: code that processes a request and writes a response.
+  * **Default mux pattern** (quick demos): use `http.HandleFunc` + `ListenAndServe(..., nil)`
-  * **ResponseWriter**: used to write headers/status/body.
+  * **Custom mux pattern** (recommended): `mux := http.NewServeMux()` and pass it to server
-  * **Request**: contains method, URL, headers, body, context.
+  * **Middleware pattern**: wrap handlers (logging, auth, recover, rate limit)
-  * **ServeMux (router)**: maps URL paths to handlers.
+==== Production notes (important) ====
+For production, prefer `http.Server{...}` with timeouts and graceful shutdown.
+Time-outs help protect against slow-client attacks and avoid hanging connections.
 ==== Related pages ====
-  * [[go:stdlib:http_server_listenandserve|http.ListenAndServe]]
+  * [[go:stdlib:http_server_struct|http.Server]]
-  * [[go:stdlib:http_server|http.Server]]
+  * [[go:stdlib:http_listenandserve|http.ListenAndServe]]
   * [[go:stdlib:http_client|http.Client]]
   * [[go:stdlib:middleware|Middleware]]
+  * [[go:stdlib:httptest|httptest]]
 ==== Hard words (English) ====
@@ Line 52: / Line 71: @@
   * **service** /ˈsɝːvɪs/: dịch vụ
   * **listen** /ˈlɪsən/: lắng nghe (mở cổng nhận kết nối)
-  * **handle** /ˈhændəl/: xử lý
+  * **accept** /əkˈsept/: chấp nhận kết nối/nhận vào
-  * **request** /rɪˈkwest/: yêu cầu
+  * **handler** /ˈhændlər/: bộ xử lý request
-  * **response** /rɪˈspɑːns/: phản hồi
+  * **interface** /ˈɪntərfeɪs/: giao diện (hợp đồng)
-  * **status code** /ˈsteɪtəs koʊd/: mã trạng thái (200, 404, 500...)
+  * **adapter** /əˈdæptər/: bộ chuyển/đệm để khớp kiểu
-  * **header** /ˈhedər/: header (thông tin kèm theo)
-  * **body** /ˈbɑːdi/: nội dung
   * **router** /ˈruːtər/: bộ định tuyến (map path -> handler)
-  * **health check** /helθ tʃek/: kiểm tra tình trạng
+  * **multiplexer (mux)** /ˈmʌltɪˌpleksər/: bộ chọn route theo đường dẫn
+  * **webhook** /ˈwebhʊk/: callback qua HTTP
+  * **load balancer** /ˈloʊd ˌbælənser/: cân bằng tải
+  * **middleware** /ˈmɪdəlwer/: lớp trung gian (bọc handler)
+  * **graceful shutdown** /ˈɡreɪsfəl ˈʃʌtdaʊn/: tắt êm
+  * **timeout** /ˈtaɪmaʊt/: hết thời gian chờ
+  * **hanging** /ˈhæŋɪŋ/: treo/chờ mãi