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package chromedp_test
import (
"bytes"
"context"
"fmt"
"io"
"io/ioutil"
"log"
"net/http"
"net/http/httptest"
"os"
"path/filepath"
"strings"
"time"
"github.com/chromedp/cdproto/cdp"
"github.com/chromedp/cdproto/dom"
"github.com/chromedp/cdproto/page"
"github.com/chromedp/cdproto/runtime"
"github.com/chromedp/cdproto/target"
"github.com/chromedp/chromedp"
"github.com/chromedp/chromedp/device"
)
func writeHTML(content string) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "text/html")
io.WriteString(w, strings.TrimSpace(content))
})
}
func ExampleTitle() {
ctx, cancel := chromedp.NewContext(context.Background())
defer cancel()
ts := httptest.NewServer(writeHTML(`
<head>
<title>fancy website title</title>
</head>
<body>
<div id="content"></div>
</body>
`))
defer ts.Close()
var title string
if err := chromedp.Run(ctx,
chromedp.Navigate(ts.URL),
chromedp.Title(&title),
); err != nil {
panic(err)
}
fmt.Println(title)
// Output:
// fancy website title
}
func ExampleExecAllocator() {
dir, err := ioutil.TempDir("", "chromedp-example")
if err != nil {
panic(err)
}
defer os.RemoveAll(dir)
opts := append(chromedp.DefaultExecAllocatorOptions[:],
chromedp.DisableGPU,
chromedp.UserDataDir(dir),
)
allocCtx, cancel := chromedp.NewExecAllocator(context.Background(), opts...)
defer cancel()
// also set up a custom logger
taskCtx, cancel := chromedp.NewContext(allocCtx, chromedp.WithLogf(log.Printf))
defer cancel()
// ensure that the browser process is started
if err := chromedp.Run(taskCtx); err != nil {
panic(err)
}
path := filepath.Join(dir, "DevToolsActivePort")
bs, err := ioutil.ReadFile(path)
if err != nil {
panic(err)
}
lines := bytes.Split(bs, []byte("\n"))
fmt.Printf("DevToolsActivePort has %d lines\n", len(lines))
// Output:
// DevToolsActivePort has 2 lines
}
func ExampleNewContext_reuseBrowser() {
ts := httptest.NewServer(writeHTML(`
<body>
<script>
// Show the current cookies.
var p = document.createElement("p")
p.innerText = document.cookie
p.setAttribute("id", "cookies")
document.body.appendChild(p)
// Override the cookies.
document.cookie = "foo=bar"
</script>
</body>
`))
defer ts.Close()
// create a new browser
ctx, cancel := chromedp.NewContext(context.Background())
defer cancel()
// start the browser without a timeout
if err := chromedp.Run(ctx); err != nil {
panic(err)
}
for i := 0; i < 2; i++ {
// look at the page twice, with a timeout set up; we skip
// cancels for the sake of brevity
ctx, _ := context.WithTimeout(ctx, time.Second)
ctx, _ = chromedp.NewContext(ctx)
var cookies string
if err := chromedp.Run(ctx,
chromedp.Navigate(ts.URL),
chromedp.Text("#cookies", &cookies),
); err != nil {
panic(err)
}
fmt.Printf("Cookies at i=%d: %q\n", i, cookies)
}
// Output:
// Cookies at i=0: ""
// Cookies at i=1: "foo=bar"
}
func ExampleNewContext_manyTabs() {
// new browser, first tab
ctx1, cancel := chromedp.NewContext(context.Background())
defer cancel()
// ensure the first tab is created
if err := chromedp.Run(ctx1); err != nil {
panic(err)
}
// same browser, second tab
ctx2, _ := chromedp.NewContext(ctx1)
// ensure the second tab is created
if err := chromedp.Run(ctx2); err != nil {
panic(err)
}
c1 := chromedp.FromContext(ctx1)
c2 := chromedp.FromContext(ctx2)
fmt.Printf("Same browser: %t\n", c1.Browser == c2.Browser)
fmt.Printf("Same tab: %t\n", c1.Target == c2.Target)
// Output:
// Same browser: true
// Same tab: false
}
func ExampleListenTarget_consoleLog() {
ctx, cancel := chromedp.NewContext(context.Background())
defer cancel()
ts := httptest.NewServer(writeHTML(`
<body>
<script>
console.log("hello js world")
console.warn("scary warning", 123)
null.throwsException
</script>
</body>
`))
defer ts.Close()
gotException := make(chan bool, 1)
chromedp.ListenTarget(ctx, func(ev interface{}) {
switch ev := ev.(type) {
case *runtime.EventConsoleAPICalled:
fmt.Printf("* console.%s call:\n", ev.Type)
for _, arg := range ev.Args {
fmt.Printf("%s - %s\n", arg.Type, arg.Value)
}
case *runtime.EventExceptionThrown:
fmt.Printf("* %s\n", ev.ExceptionDetails)
gotException <- true
}
})
if err := chromedp.Run(ctx, chromedp.Navigate(ts.URL)); err != nil {
panic(err)
}
<-gotException
// Output:
// * console.log call:
// string - "hello js world"
// * console.warning call:
// string - "scary warning"
// number - 123
// * encountered exception 'Uncaught' (4:6)
}
func ExampleWaitNewTarget() {
ctx, cancel := chromedp.NewContext(context.Background())
defer cancel()
mux := http.NewServeMux()
mux.Handle("/first", writeHTML(`
<input id='newtab' type='button' value='open' onclick='window.open("/second", "_blank");'/>
`))
mux.Handle("/second", writeHTML(``))
ts := httptest.NewServer(mux)
defer ts.Close()
// Grab the first spawned tab that isn't blank.
ch := chromedp.WaitNewTarget(ctx, func(info *target.Info) bool {
return info.URL != ""
})
if err := chromedp.Run(ctx,
chromedp.Navigate(ts.URL+"/first"),
chromedp.Click("#newtab", chromedp.ByID),
); err != nil {
panic(err)
}
newCtx, cancel := chromedp.NewContext(ctx, chromedp.WithTargetID(<-ch))
defer cancel()
var urlstr string
if err := chromedp.Run(newCtx, chromedp.Location(&urlstr)); err != nil {
panic(err)
}
fmt.Println("new tab's path:", strings.TrimPrefix(urlstr, ts.URL))
// Output:
// new tab's path: /second
}
func ExampleListenTarget_acceptAlert() {
ctx, cancel := chromedp.NewContext(context.Background())
defer cancel()
mux := http.NewServeMux()
mux.Handle("/second", writeHTML(``))
ts := httptest.NewServer(writeHTML(`
<input id='alert' type='button' value='alert' onclick='alert("alert text");'/>
`))
defer ts.Close()
chromedp.ListenTarget(ctx, func(ev interface{}) {
if ev, ok := ev.(*page.EventJavascriptDialogOpening); ok {
fmt.Println("closing alert:", ev.Message)
go func() {
if err := chromedp.Run(ctx,
page.HandleJavaScriptDialog(true),
); err != nil {
panic(err)
}
}()
}
})
if err := chromedp.Run(ctx,
chromedp.Navigate(ts.URL),
chromedp.Click("#alert", chromedp.ByID),
); err != nil {
panic(err)
}
// Output:
// closing alert: alert text
}
func Example_retrieveHTML() {
ctx, cancel := chromedp.NewContext(context.Background())
defer cancel()
ts := httptest.NewServer(writeHTML(`
<body>
<p id="content" onclick="changeText()">Original content.</p>
<script>
function changeText() {
document.getElementById("content").textContent = "New content!"
}
</script>
</body>
`))
defer ts.Close()
var outerBefore, outerAfter string
if err := chromedp.Run(ctx,
chromedp.Navigate(ts.URL),
chromedp.OuterHTML("#content", &outerBefore),
chromedp.Click("#content", chromedp.ByID),
chromedp.OuterHTML("#content", &outerAfter),
); err != nil {
panic(err)
}
fmt.Println("OuterHTML before clicking:")
fmt.Println(outerBefore)
fmt.Println("OuterHTML after clicking:")
fmt.Println(outerAfter)
// Output:
// OuterHTML before clicking:
// <p id="content" onclick="changeText()">Original content.</p>
// OuterHTML after clicking:
// <p id="content" onclick="changeText()">New content!</p>
}
func ExampleEmulate() {
ctx, cancel := chromedp.NewContext(context.Background())
defer cancel()
var buf []byte
if err := chromedp.Run(ctx,
chromedp.Emulate(device.IPhone7),
chromedp.Navigate(`https://google.com/`),
chromedp.WaitVisible(`#main`, chromedp.ByID),
chromedp.SendKeys(`input[name=q]`, "what's my user agent?\n"),
chromedp.WaitVisible(`#rso`, chromedp.ByID),
chromedp.CaptureScreenshot(&buf),
); err != nil {
panic(err)
}
if err := ioutil.WriteFile("google-iphone7.png", buf, 0644); err != nil {
panic(err)
}
}
func ExamplePrintToPDF() {
ctx, cancel := chromedp.NewContext(context.Background())
defer cancel()
var buf []byte
if err := chromedp.Run(ctx,
chromedp.Navigate(`https://godoc.org/github.com/chromedp/chromedp`),
chromedp.ActionFunc(func(ctx context.Context) error {
var err error
buf, _, err = page.PrintToPDF().
WithDisplayHeaderFooter(false).
WithLandscape(true).
Do(ctx)
return err
}),
); err != nil {
panic(err)
}
if err := ioutil.WriteFile("page.pdf", buf, 0644); err != nil {
panic(err)
}
}
func ExampleByJSPath() {
ctx, cancel := chromedp.NewContext(context.Background())
defer cancel()
ts := httptest.NewServer(writeHTML(`
<body>
<div id="content">cool content</div>
</body>
`))
defer ts.Close()
var ids []cdp.NodeID
var html string
if err := chromedp.Run(ctx,
chromedp.Navigate(ts.URL),
chromedp.NodeIDs(`document`, &ids, chromedp.ByJSPath),
chromedp.ActionFunc(func(ctx context.Context) error {
var err error
html, err = dom.GetOuterHTML().WithNodeID(ids[0]).Do(ctx)
return err
}),
); err != nil {
panic(err)
}
fmt.Println("Outer HTML:")
fmt.Println(html)
// Output:
// Outer HTML:
// <html><head></head><body>
// <div id="content">cool content</div>
// </body></html>
}
func Example_documentDump() {
ctx, cancel := chromedp.NewContext(context.Background())
defer cancel()
ts := httptest.NewServer(writeHTML(`<!doctype html>
<html>
<body>
<div id="content">the content</div>
</body>
</html>`))
defer ts.Close()
const expr = `(function(d, id, v) {
var b = d.querySelector('body');
var el = d.createElement('div');
el.id = id;
el.innerText = v;
b.insertBefore(el, b.childNodes[0]);
})(document, %q, %q);`
var nodes []*cdp.Node
if err := chromedp.Run(ctx,
chromedp.Navigate(ts.URL),
chromedp.Nodes(`document`, &nodes, chromedp.ByJSPath),
chromedp.WaitVisible(`#content`),
chromedp.ActionFunc(func(ctx context.Context) error {
s := fmt.Sprintf(expr, "thing", "a new thing!")
_, exp, err := runtime.Evaluate(s).Do(ctx)
if err != nil {
return err
}
if exp != nil {
return exp
}
return nil
}),
chromedp.WaitVisible(`#thing`),
); err != nil {
panic(err)
}
fmt.Println("Document tree:")
fmt.Print(nodes[0].Dump(" ", " ", false))
// Output:
// Document tree:
// #document <Document>
// html <DocumentType>
// html
// head
// body
// div#thing
// #text "a new thing!"
// div#content
// #text "the content"
}
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