1 // Copyright 2011 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 /* 6 Package http provides HTTP client and server implementations. 7 8 Get, Head, Post, and PostForm make HTTP (or HTTPS) requests: 9 10 resp, err := http.Get("http://example.com/") 11 ... 12 resp, err := http.Post("http://example.com/upload", "image/jpeg", &buf) 13 ... 14 resp, err := http.PostForm("http://example.com/form", 15 url.Values{"key": {"Value"}, "id": {"123"}}) 16 17 The client must close the response body when finished with it: 18 19 resp, err := http.Get("http://example.com/") 20 if err != nil { 21 // handle error 22 } 23 defer resp.Body.Close() 24 body, err := ioutil.ReadAll(resp.Body) 25 // ... 26 27 For control over HTTP client headers, redirect policy, and other 28 settings, create a Client: 29 30 client := &http.Client{ 31 CheckRedirect: redirectPolicyFunc, 32 } 33 34 resp, err := client.Get("http://example.com") 35 // ... 36 37 req, err := http.NewRequest("GET", "http://example.com", nil) 38 // ... 39 req.Header.Add("If-None-Match", `W/"wyzzy"`) 40 resp, err := client.Do(req) 41 // ... 42 43 For control over proxies, TLS configuration, keep-alives, 44 compression, and other settings, create a Transport: 45 46 tr := &http.Transport{ 47 MaxIdleConns: 10, 48 IdleConnTimeout: 30 * time.Second, 49 DisableCompression: true, 50 } 51 client := &http.Client{Transport: tr} 52 resp, err := client.Get("https://example.com") 53 54 Clients and Transports are safe for concurrent use by multiple 55 goroutines and for efficiency should only be created once and re-used. 56 57 ListenAndServe starts an HTTP server with a given address and handler. 58 The handler is usually nil, which means to use DefaultServeMux. 59 Handle and HandleFunc add handlers to DefaultServeMux: 60 61 http.Handle("/foo", fooHandler) 62 63 http.HandleFunc("/bar", func(w http.ResponseWriter, r *http.Request) { 64 fmt.Fprintf(w, "Hello, %q", html.EscapeString(r.URL.Path)) 65 }) 66 67 log.Fatal(http.ListenAndServe(":8080", nil)) 68 69 More control over the server's behavior is available by creating a 70 custom Server: 71 72 s := &http.Server{ 73 Addr: ":8080", 74 Handler: myHandler, 75 ReadTimeout: 10 * time.Second, 76 WriteTimeout: 10 * time.Second, 77 MaxHeaderBytes: 1 << 20, 78 } 79 log.Fatal(s.ListenAndServe()) 80 81 Starting with Go 1.6, the http package has transparent support for the 82 HTTP/2 protocol when using HTTPS. Programs that must disable HTTP/2 83 can do so by setting Transport.TLSNextProto (for clients) or 84 Server.TLSNextProto (for servers) to a non-nil, empty 85 map. Alternatively, the following GODEBUG environment variables are 86 currently supported: 87 88 GODEBUG=http2client=0 # disable HTTP/2 client support 89 GODEBUG=http2server=0 # disable HTTP/2 server support 90 GODEBUG=http2debug=1 # enable verbose HTTP/2 debug logs 91 GODEBUG=http2debug=2 # ... even more verbose, with frame dumps 92 93 The GODEBUG variables are not covered by Go's API compatibility 94 promise. Please report any issues before disabling HTTP/2 95 support: https://golang.org/s/http2bug 96 97 The http package's Transport and Server both automatically enable 98 HTTP/2 support for simple configurations. To enable HTTP/2 for more 99 complex configurations, to use lower-level HTTP/2 features, or to use 100 a newer version of Go's http2 package, import "golang.org/x/net/http2" 101 directly and use its ConfigureTransport and/or ConfigureServer 102 functions. Manually configuring HTTP/2 via the golang.org/x/net/http2 103 package takes precedence over the net/http package's built-in HTTP/2 104 support. 105 106 */ 107 package http 108