add Element.Resource

markusbkk · Feb 12, 2020 · ad6ffb4 · ad6ffb4
1 parent 2cebc7d
commit ad6ffb4
Show file tree

Hide file tree

Showing 7 changed files with 75 additions and 11 deletions.
diff --git a/browser.go b/browser.go
@@ -114,14 +114,21 @@ func (b *Browser) PageE(url string) (*Page, error) {
 	target, err := b.Call(&cdp.Message{
 		Method: "Target.createTarget",
 		Params: cdp.Object{
-			"url": url,
+			"url": "about:blank",
 		},
 	})
 	if err != nil {
 		return nil, err
 	}
 
-	return b.page(target.Get("targetId").String())
+	page, err := b.page(target.Get("targetId").String())
+	if err != nil {
+		return nil, err
+	}
+
+	page.Navigate(url)
+
+	return page, nil
 }
 
 // Page creates a new page

diff --git a/element.go b/element.go
@@ -2,6 +2,7 @@ package rod
 
 import (
 	"context"
+	"encoding/base64"
 	"encoding/json"
 	"fmt"
 	"path/filepath"
@@ -45,7 +46,7 @@ func (el *Element) CancelTimeout() {
 
 // DescribeE ...
 func (el *Element) DescribeE() (kit.JSONResult, error) {
-	node, err := el.page.Ctx(el.ctx).Call(
+	val, err := el.page.Ctx(el.ctx).Call(
 		"DOM.describeNode",
 		cdp.Object{
 			"objectId": el.ObjectID,
@@ -54,16 +55,16 @@ func (el *Element) DescribeE() (kit.JSONResult, error) {
 	if err != nil {
 		return nil, err
 	}
-	return node, nil
+	node := val.Get("node")
+	return &node, nil
 }
 
 // Describe returns the element info
 // Returned json: https://chromedevtools.github.io/devtools-protocol/tot/DOM#type-Node
 func (el *Element) Describe() kit.JSONResult {
-	info, err := el.DescribeE()
+	node, err := el.DescribeE()
 	kit.E(err)
-	val := info.Get("node")
-	return &val
+	return node
 }
 
 // FrameE ...
@@ -74,7 +75,7 @@ func (el *Element) FrameE() (*Page, error) {
 	}
 
 	newPage := *el.page
-	newPage.FrameID = node.Get("node.frameId").String()
+	newPage.FrameID = node.Get("frameId").String()
 	newPage.element = el
 
 	return &newPage, newPage.initIsolatedWorld()
@@ -399,6 +400,49 @@ func (el *Element) Box() kit.JSONResult {
 	return box
 }
 
+// ResourceE ...
+func (el *Element) ResourceE() ([]byte, error) {
+	src, err := el.EvalE(true, `() => new Promise((resolve, reject) => {
+		if (this.complete) {
+			return resolve(this.src)
+		}
+		this.addEventListener('onload', () => resolve(this.src))
+		this.addEventListener('onerror', (e) => reject(e))
+	})`)
+	if err != nil {
+		return nil, err
+	}
+
+	res, err := el.page.Call("Page.getResourceContent", cdp.Object{
+		"frameId": el.page.FrameID,
+		"url":     src.String(),
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	data := res.Get("content").String()
+
+	var bin []byte
+	if res.Get("base64Encoded").Bool() {
+		bin, err = base64.StdEncoding.DecodeString(data)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		bin = []byte(data)
+	}
+
+	return bin, nil
+}
+
+// Resource returns the binary of the "src" properly, such as the image or audio file.
+func (el *Element) Resource() []byte {
+	bin, err := el.ResourceE()
+	kit.E(err)
+	return bin
+}
+
 // EvalE ...
 func (el *Element) EvalE(byValue bool, js string, params ...interface{}) (kit.JSONResult, error) {
 	return el.page.EvalE(byValue, el.ObjectID, js, params)

diff --git a/element_test.go b/element_test.go
@@ -136,6 +136,11 @@ func (s *S) TestWaitStable() {
 	p.Has("[event=click]")
 }
 
+func (s *S) TestResource() {
+	p := s.page.Navigate(s.htmlFile("fixtures/resource.html"))
+	s.Equal(15148, len(p.Element("img").Resource()))
+}
+
 func (s *S) TestFnErr() {
 	p := s.page.Navigate(s.htmlFile("fixtures/click.html"))
 	el := p.Element("button")

diff --git a/error.go b/error.go
@@ -9,6 +9,8 @@ const (
 	ErrExpectElements = "expect js to return an array of elements"
 	// ErrElementNotFound error code
 	ErrElementNotFound = "cannot find element"
+	// ErrSrcNotFound error code
+	ErrSrcNotFound = "element doesn't have src attribute"
 )
 
 // Error ...

diff --git a/fixtures/resource.html b/fixtures/resource.html
@@ -0,0 +1,5 @@
+<html>
+    <body>
+        <img src="./rod.png" alt="img">
+    </body>
+</html>
diff --git a/fixtures/rod.png b/fixtures/rod.png
diff --git a/page.go b/page.go
@@ -21,13 +21,13 @@ type Page struct {
 	TargetID  string
 	SessionID string
 	ContextID int64
+	FrameID   string
 
 	// devices
 	Mouse    *Mouse
 	Keyboard *Keyboard
 
 	// iframe only
-	FrameID string
 	element *Element
 
 	timeoutCancel       func()
@@ -57,9 +57,10 @@ func (p *Page) CancelTimeout() {
 
 // NavigateE ...
 func (p *Page) NavigateE(url string) error {
-	_, err := p.Call("Page.navigate", cdp.Object{
+	res, err := p.Call("Page.navigate", cdp.Object{
 		"url": url,
 	})
+	p.FrameID = res.Get("frameId").String()
 	return err
 }
 
@@ -447,7 +448,7 @@ func (p *Page) initSession() error {
 }
 
 func (p *Page) isIframe() bool {
-	return p.FrameID != ""
+	return p.element != nil
 }
 
 func (p *Page) rootFrame() *Page {