forked from ahmetb/go-httpbin
/
handlers.go
682 lines (601 loc) · 19.6 KB
/
handlers.go
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// Package httpbin providers HTTP handlers for httpbin.org endpoints and a
// multiplexer to directly hook it up to any http.Server or httptest.Server.
package httpbin
import (
"compress/flate"
"compress/gzip"
"encoding/json"
"fmt"
"image"
"image/color"
"image/gif"
"image/jpeg"
"image/png"
"io"
"io/ioutil"
"math"
"math/rand"
"net"
"net/http"
"strconv"
"strings"
"time"
"github.com/andybalholm/brotli"
"github.com/gorilla/mux"
"github.com/pkg/errors"
)
var (
// BinaryChunkSize is buffer length used for stuff like generating
// large blobs.
BinaryChunkSize = 64 * 1024
// DelayMax is the maximum execution time for /delay endpoint.
DelayMax = 10 * time.Second
// StreamInterval is the default interval between writing objects to the stream.
StreamInterval = 1 * time.Second
)
// GetMux returns the mux with handlers for httpbin endpoints registered.
func GetMux() *mux.Router {
r := mux.NewRouter()
r.HandleFunc(`/`, HomeHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/ip`, IPHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/user-agent`, UserAgentHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/headers`, HeadersHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/get`, GetHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/post`, PostHandler).Methods(http.MethodPost)
r.HandleFunc(`/redirect/{n:[\d]+}`, RedirectHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/absolute-redirect/{n:[\d]+}`, AbsoluteRedirectHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/redirect-to`, RedirectToHandler).Methods(http.MethodGet, http.MethodHead).Queries("url", "{url:.+}")
r.HandleFunc(`/status/{code:[\d]+}`, StatusHandler)
r.HandleFunc(`/bytes/{n:[\d]+}`, BytesHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/delay/{n:\d+(?:\.\d+)?}`, DelayHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/stream/{n:[\d]+}`, StreamHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/drip`, DripHandler).Methods(http.MethodGet, http.MethodHead).Queries(
"numbytes", `{numbytes:\d+}`,
"duration", `{duration:\d+(?:\.\d+)?}`)
r.HandleFunc(`/cookies`, CookiesHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/cookies/set`, SetCookiesHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/cookies/delete`, DeleteCookiesHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/cache`, CacheHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/cache/{n:[\d]+}`, SetCacheHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/gzip`, GZIPHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/brotli`, BrotliHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/deflate`, DeflateHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/html`, HTMLHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/xml`, XMLHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/robots.txt`, RobotsTXTHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/deny`, DenyHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/basic-auth/{u}/{p}`, BasicAuthHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/hidden-basic-auth/{u}/{p}`, HiddenBasicAuthHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/image/gif`, GIFHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/image/png`, PNGHandler).Methods(http.MethodGet, http.MethodHead)
r.HandleFunc(`/image/jpeg`, JPEGHandler).Methods(http.MethodGet, http.MethodHead)
return r
}
// HomeHandler serves static HTML content for the index page.
func HomeHandler(w http.ResponseWriter, r *http.Request) {
fmt.Fprintf(w, `<!DOCTYPE html>
<html lang="en">
<head>
<title>go-httpbin</title>
<head>
<body>
<h1>go-httpbin</h1>
<p>
<a href="https://github.com/ahmetb/go-httpbin">
Read documentation →
</a>
</body>
</html>`)
}
// IPHandler returns Origin IP.
func IPHandler(w http.ResponseWriter, r *http.Request) {
h, _, _ := net.SplitHostPort(r.RemoteAddr)
if err := writeJSON(w, ipResponse{h}); err != nil {
writeErrorJSON(w, errors.Wrap(err, "failed to write json")) // TODO handle this error in writeJSON(w,v)
}
}
// UserAgentHandler returns user agent.
func UserAgentHandler(w http.ResponseWriter, r *http.Request) {
if err := writeJSON(w, userAgentResponse{r.UserAgent()}); err != nil {
writeErrorJSON(w, errors.Wrap(err, "failed to write json"))
}
}
// HeadersHandler returns user agent.
func HeadersHandler(w http.ResponseWriter, r *http.Request) {
if err := writeJSON(w, headersResponse{getHeaders(r)}); err != nil {
writeErrorJSON(w, errors.Wrap(err, "failed to write json"))
}
}
// GetHandler returns user agent.
func GetHandler(w http.ResponseWriter, r *http.Request) {
h, _, _ := net.SplitHostPort(r.RemoteAddr)
v := getResponse{
headersResponse: headersResponse{getHeaders(r)},
ipResponse: ipResponse{h},
Args: flattenValues(r.URL.Query()),
}
if err := writeJSON(w, v); err != nil {
writeErrorJSON(w, errors.Wrap(err, "failed to write json"))
}
}
// PostHandler accept a post and echo its data back
func PostHandler(w http.ResponseWriter, r *http.Request) {
h, _, _ := net.SplitHostPort(r.RemoteAddr)
data, err := parseData(r)
if err != nil {
writeErrorJSON(w, errors.Wrap(err, "failed to read body"))
return
}
var jsonPayload interface{}
if strings.Contains(r.Header.Get("Content-Type"), "json") {
err := json.Unmarshal(data, &jsonPayload)
if err != nil {
writeErrorJSON(w, errors.Wrap(err, "failed to read body"))
return
}
}
v := postResponse{
headersResponse: headersResponse{getHeaders(r)},
ipResponse: ipResponse{h},
Args: flattenValues(r.URL.Query()),
Data: string(data),
JSON: jsonPayload,
}
if err := writeJSON(w, v); err != nil {
writeErrorJSON(w, errors.Wrap(err, "failed to write json"))
}
}
// RedirectHandler returns a 302 Found response if n=1 pointing
// to /get, otherwise to /redirect/(n-1)
func RedirectHandler(w http.ResponseWriter, r *http.Request) {
n := mux.Vars(r)["n"]
i, _ := strconv.Atoi(n) // shouldn't fail due to route pattern
var loc string
if i <= 1 {
loc = "/get"
} else {
loc = fmt.Sprintf("/redirect/%d", i-1)
}
w.Header().Set("Location", loc)
w.WriteHeader(http.StatusFound)
}
// AbsoluteRedirectHandler returns a 302 Found response if n=1 pointing
// to /host/get, otherwise to /host/absolute-redirect/(n-1)
func AbsoluteRedirectHandler(w http.ResponseWriter, r *http.Request) {
n := mux.Vars(r)["n"]
i, _ := strconv.Atoi(n) // shouldn't fail due to route pattern
var loc string
if i <= 1 {
loc = "/get"
} else {
loc = fmt.Sprintf("/absolute-redirect/%d", i-1)
}
w.Header().Set("Location", "http://"+r.Host+loc)
w.WriteHeader(http.StatusFound)
}
// RedirectToHandler returns a 302 Found response pointing to
// the url query parameter
func RedirectToHandler(w http.ResponseWriter, r *http.Request) {
u := mux.Vars(r)["url"]
w.Header().Set("Location", u)
w.WriteHeader(http.StatusFound)
}
// StatusHandler returns a proper response for provided status code
func StatusHandler(w http.ResponseWriter, r *http.Request) {
code, _ := strconv.Atoi(mux.Vars(r)["code"])
statusWritten := false
switch code {
case http.StatusMovedPermanently,
http.StatusFound,
http.StatusSeeOther,
http.StatusUseProxy,
http.StatusTemporaryRedirect:
w.Header().Set("Location", "/redirect/1")
case http.StatusUnauthorized: // 401
w.Header().Set("WWW-Authenticate", `Basic realm="Fake Realm"`)
case http.StatusPaymentRequired: // 402
w.WriteHeader(code)
statusWritten = true
io.WriteString(w, "Fuck you, pay me!")
w.Header().Set("x-more-info", "http://vimeo.com/22053820")
case http.StatusNotAcceptable: // 406
w.WriteHeader(code)
statusWritten = true
io.WriteString(w, `{"message": "Client did not request a supported media type.", "accept": ["image/webp", "image/svg+xml", "image/jpeg", "image/png", "image/*"]}`)
case http.StatusTeapot:
w.WriteHeader(code)
statusWritten = true
w.Header().Set("x-more-info", "http://tools.ietf.org/html/rfc2324")
io.WriteString(w, `
-=[ teapot ]=-
_...._
.' _ _ '.
| ." ^ ". _,
\_;'"---"'|//
| ;/
\_ _/
'"""'
`)
}
if !statusWritten {
w.WriteHeader(code)
}
}
// BytesHandler returns n random bytes of binary data and accepts an
// optional 'seed' integer query parameter.
func BytesHandler(w http.ResponseWriter, r *http.Request) {
n, _ := strconv.Atoi(mux.Vars(r)["n"]) // shouldn't fail due to route pattern
seedStr := r.URL.Query().Get("seed")
if seedStr == "" {
seedStr = fmt.Sprintf("%d", time.Now().UnixNano())
}
seed, _ := strconv.ParseInt(seedStr, 10, 64) // shouldn't fail due to route pattern
rnd := rand.New(rand.NewSource(seed))
buf := make([]byte, BinaryChunkSize)
for n > 0 {
rnd.Read(buf) // will never return err
if n >= len(buf) {
n -= len(buf)
w.Write(buf)
} else {
// last chunk
w.Write(buf[:n])
break
}
}
}
// DelayHandler delays responding for min(n, 10) seconds and responds
// with /get endpoint
func DelayHandler(w http.ResponseWriter, r *http.Request) {
n, _ := strconv.ParseFloat(mux.Vars(r)["n"], 64) // shouldn't fail due to route pattern
// allow only millisecond precision
duration := time.Millisecond * time.Duration(n*float64(time.Second/time.Millisecond))
if duration > DelayMax {
duration = DelayMax
}
time.Sleep(duration)
GetHandler(w, r)
}
// StreamHandler writes a json object to a new line every second.
func StreamHandler(w http.ResponseWriter, r *http.Request) {
n, _ := strconv.Atoi(mux.Vars(r)["n"]) // shouldn't fail due to route pattern
nl := []byte{'\n'}
// allow only millisecond precision
for i := 0; i < n; i++ {
time.Sleep(StreamInterval)
b, _ := json.Marshal(struct {
N int `json:"n"`
Time time.Time `json:"time"`
}{i, time.Now().UTC()})
w.Write(b)
w.Write(nl)
if f, ok := w.(http.Flusher); ok {
f.Flush()
}
}
}
// CookiesHandler returns the cookies provided in the request.
func CookiesHandler(w http.ResponseWriter, r *http.Request) {
if err := writeJSON(w, cookiesResponse{getCookies(r.Cookies())}); err != nil {
writeErrorJSON(w, errors.Wrap(err, "failed to write json"))
}
}
// SetCookiesHandler sets the query key/value pairs as cookies
// in the response and returns a 302 redirect to /cookies.
func SetCookiesHandler(w http.ResponseWriter, r *http.Request) {
for k := range r.URL.Query() {
v := r.URL.Query().Get(k)
http.SetCookie(w, &http.Cookie{
Name: k,
Value: v,
Path: "/",
})
}
w.Header().Set("Location", "/cookies")
w.WriteHeader(http.StatusFound)
}
// DeleteCookiesHandler deletes cookies with provided query value keys
// in the response by settings a Unix epoch expiration date and returns
// a 302 redirect to /cookies.
func DeleteCookiesHandler(w http.ResponseWriter, r *http.Request) {
for k := range r.URL.Query() {
http.SetCookie(w, &http.Cookie{
Name: k,
Value: "",
Path: "/",
Expires: time.Unix(0, 0),
MaxAge: 0,
})
}
w.Header().Set("Location", "/cookies")
w.WriteHeader(http.StatusFound)
}
// DripHandler drips data over a duration after an optional initial delay,
// then optionally returns with the given status code.
func DripHandler(w http.ResponseWriter, r *http.Request) {
var retCode int
retCodeStr := r.URL.Query().Get("code")
delayStr := r.URL.Query().Get("delay")
durationSec, _ := strconv.ParseFloat(mux.Vars(r)["duration"], 32) // shouldn't fail due to route pattern
numBytes, _ := strconv.Atoi(mux.Vars(r)["numbytes"]) // shouldn't fail due to route pattern
if retCodeStr != "" { // optional: status code
var err error
retCode, err = strconv.Atoi(r.URL.Query().Get("code"))
if err != nil {
writeErrorJSON(w, errors.New("failed to parse 'code'"))
return
}
w.WriteHeader(retCode)
}
if delayStr != "" { // optional: initial delay
delaySec, err := strconv.ParseFloat(r.URL.Query().Get("delay"), 64)
if err != nil {
writeErrorJSON(w, errors.New("failed to parse 'delay'"))
return
}
delayMs := (time.Second / time.Millisecond) * time.Duration(delaySec)
time.Sleep(delayMs * time.Millisecond)
}
t := time.Second * time.Duration(durationSec) / time.Duration(numBytes)
for i := 0; i < numBytes; i++ {
w.Write([]byte{'*'})
if f, ok := w.(http.Flusher); ok {
f.Flush()
}
time.Sleep(t)
}
}
// CacheHandler returns 200 with the response of /get unless an If-Modified-Since
//or If-None-Match header is provided, when it returns a 304.
func CacheHandler(w http.ResponseWriter, r *http.Request) {
if r.Header.Get("If-Modified-Since") != "" || r.Header.Get("If-None-Match") != "" {
w.WriteHeader(http.StatusNotModified)
return
}
GetHandler(w, r)
}
// SetCacheHandler sets a Cache-Control header for n seconds and returns with
// the /get response.
func SetCacheHandler(w http.ResponseWriter, r *http.Request) {
n, _ := strconv.Atoi(mux.Vars(r)["n"]) // shouldn't fail due to route pattern
w.Header().Set("Cache-Control", fmt.Sprintf("public, max-age=%d", n))
GetHandler(w, r)
}
// GZIPHandler returns a GZIP-encoded response
func GZIPHandler(w http.ResponseWriter, r *http.Request) {
h, _, _ := net.SplitHostPort(r.RemoteAddr)
v := gzipResponse{
headersResponse: headersResponse{getHeaders(r)},
ipResponse: ipResponse{h},
Gzipped: true,
}
w.Header().Set("Content-Type", "application/json")
w.Header().Add("Content-Encoding", "gzip")
ww := gzip.NewWriter(w)
defer ww.Close() // flush
if err := writeJSON(ww, v); err != nil {
writeErrorJSON(w, errors.Wrap(err, "failed to write json"))
}
}
// DeflateHandler returns a DEFLATE-encoded response.
func DeflateHandler(w http.ResponseWriter, r *http.Request) {
h, _, _ := net.SplitHostPort(r.RemoteAddr)
v := deflateResponse{
headersResponse: headersResponse{getHeaders(r)},
ipResponse: ipResponse{h},
Deflated: true,
}
w.Header().Set("Content-Encoding", "deflate")
ww, _ := flate.NewWriter(w, flate.BestCompression)
defer ww.Close() // flush
if err := writeJSON(ww, v); err != nil {
writeErrorJSON(w, errors.Wrap(err, "failed to write json"))
}
}
// BrotliHandler returns a Brotli-encoded response
func BrotliHandler(w http.ResponseWriter, r *http.Request) {
h, _, _ := net.SplitHostPort(r.RemoteAddr)
v := brotliResponse{
headersResponse: headersResponse{getHeaders(r)},
ipResponse: ipResponse{h},
Compressed: true,
}
w.Header().Set("Content-Type", "application/json")
w.Header().Add("Content-Encoding", "br")
ww := brotli.NewWriter(w)
defer ww.Close() // flush
if err := writeJSON(ww, v); err != nil {
writeErrorJSON(w, errors.Wrap(err, "failed to write json"))
}
}
// RobotsTXTHandler returns a robots.txt response.
func RobotsTXTHandler(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "text/plain")
fmt.Fprint(w, "User-agent: *\nDisallow: /deny\n")
}
// DenyHandler returns a plain-text response.
func DenyHandler(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "text/plain")
fmt.Fprint(w, `
.-''''''-.
.' _ _ '.
/ O O \
: :
| |
: __ :
\ .-"' '"-. /
'. .'
'-......-'
YOU SHOULDN'T BE HERE
`)
}
// BasicAuthHandler challenges with given username and password.
func BasicAuthHandler(w http.ResponseWriter, r *http.Request) {
basicAuthHandler(w, r, http.StatusUnauthorized)
}
// HiddenBasicAuthHandler challenges with given username and password and
// returns 404 if authentication fails.
func HiddenBasicAuthHandler(w http.ResponseWriter, r *http.Request) {
basicAuthHandler(w, r, http.StatusNotFound)
}
func basicAuthHandler(w http.ResponseWriter, r *http.Request, status int) {
user := mux.Vars(r)["u"]
pass := mux.Vars(r)["p"]
inUser, inPass, ok := r.BasicAuth()
if !ok || inUser != user || inPass != pass {
w.WriteHeader(status)
} else {
v := basicAuthResponse{
Authenticated: true,
User: user,
}
if err := writeJSON(w, v); err != nil {
writeErrorJSON(w, errors.Wrap(err, "failed to write json"))
}
}
}
// HTMLHandler returns some HTML response.
func HTMLHandler(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "text/html")
fmt.Fprint(w, htmlData)
}
// XMLHandler returns some XML response.
func XMLHandler(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "text/xml")
fmt.Fprint(w, xmlData)
}
type circle struct {
X, Y, R float64
}
func (c *circle) Brightness(x, y float64) uint8 {
var dx, dy float64 = c.X - x, c.Y - y
d := math.Sqrt(dx*dx+dy*dy) / c.R
if d > 1 {
return 0
}
return 255
}
// GIFHandler returns an animated GIF image.
// Source: http://tech.nitoyon.com/en/blog/2016/01/07/go-animated-gif-gen/
func GIFHandler(rw http.ResponseWriter, r *http.Request) {
var w, h int = 240, 240
var hw, hh float64 = float64(w / 2), float64(h / 2)
circles := []*circle{{}, {}, {}}
var palette = []color.Color{
color.RGBA{0x00, 0x00, 0x00, 0xff},
color.RGBA{0x00, 0x00, 0xff, 0xff},
color.RGBA{0x00, 0xff, 0x00, 0xff},
color.RGBA{0x00, 0xff, 0xff, 0xff},
color.RGBA{0xff, 0x00, 0x00, 0xff},
color.RGBA{0xff, 0x00, 0xff, 0xff},
color.RGBA{0xff, 0xff, 0x00, 0xff},
color.RGBA{0xff, 0xff, 0xff, 0xff},
}
var images []*image.Paletted
var delays []int
steps := 20
for step := 0; step < steps; step++ {
img := image.NewPaletted(image.Rect(0, 0, w, h), palette)
images = append(images, img)
delays = append(delays, 0)
θ := 2.0 * math.Pi / float64(steps) * float64(step)
for i, circle := range circles {
θ0 := 2 * math.Pi / 3 * float64(i)
circle.X = hw - 40*math.Sin(θ0) - 20*math.Sin(θ0+θ)
circle.Y = hh - 40*math.Cos(θ0) - 20*math.Cos(θ0+θ)
circle.R = 50
}
for x := 0; x < w; x++ {
for y := 0; y < h; y++ {
img.Set(x, y, color.RGBA{
circles[0].Brightness(float64(x), float64(y)),
circles[1].Brightness(float64(x), float64(y)),
circles[2].Brightness(float64(x), float64(y)),
255,
})
}
}
}
gif.EncodeAll(rw, &gif.GIF{
Image: images,
Delay: delays,
})
}
// JPEGHandler returns a JPEG image.
func JPEGHandler(w http.ResponseWriter, r *http.Request) {
jpeg.Encode(w, getImg(), nil)
}
// PNGHandler returns a PNG image.
func PNGHandler(w http.ResponseWriter, r *http.Request) {
png.Encode(w, getImg())
}
func getImg() image.Image {
const n = 512
img := image.NewRGBA(image.Rect(0, 0, n, n))
abs := func(n int) int {
if n < 0 {
return -n
}
return n
}
sq := func(i int) int { return i * i }
for x := 0; x <= n; x++ {
for y := 0; y <= n; y++ {
if x == n/2 && y == n/2 {
continue
}
d := math.Sqrt(float64(sq(abs(x-n/2)) + sq(abs(y-n/2))))
if d > n/2 {
continue
}
sin := float64(y-n/2) / d
deg := math.Asin(sin)/math.Pi*359.0 + 180
sec := int(deg) / 60
var fix, mod *uint8
var inc bool
c := color.RGBA{0, 0, 0, 0xFF}
switch sec {
case 0:
fix, mod = &c.R, &c.G
inc = true
case 1:
fix, mod = &c.G, &c.R
inc = false
case 2:
fix, mod = &c.G, &c.B
inc = true
case 3:
fix, mod = &c.B, &c.G
inc = false
case 4:
fix, mod = &c.B, &c.R
inc = true
case 5:
fix, mod = &c.R, &c.B
inc = false
default:
panic(fmt.Sprintf("deg=%f sec=%d", deg, sec))
}
v := uint8((int(deg) % 60) * 255.0 / 60.0)
*fix = 255
if inc {
*mod = v
} else {
*mod = 255 - v
}
img.Set(x, y, c)
}
}
return img
}
func parseData(r *http.Request) ([]byte, error) {
if r.Body == nil {
return nil, nil
}
defer r.Body.Close()
data, err := ioutil.ReadAll(r.Body)
if err != nil {
return nil, err
}
return data, nil
}