Code cleanup

- Refactored API calls to be cleaner
- Changed types that shoudn't be exported to not-exported
- Updated examples with API changes
- Added unit test for Title action

chromedp_test.go

@@ -54,9 +54,17 @@ func TestNavigate(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-
 	if !strings.HasPrefix(urlstr, "https://www.google.") {
-		t.Errorf("expected to be on google, got: %v", urlstr)
+		t.Errorf("expected to be on google domain, at: %s", urlstr)
+	}
+
+	var title string
+	err = c.Run(defaultContext, Title(&title))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(strings.ToLower(title), "google") {
+		t.Errorf("expected title to contain google, instead title is: %s", title)
 	}
 }
 

errors.go

@@ -0,0 +1,39 @@
+package chromedp
+
+import (
+	"errors"
+)
+
+// Error types.
+var (
+	// ErrInvalidDimensions is the error returned when the retrieved box model is
+	// invalid.
+	ErrInvalidDimensions = errors.New("invalid dimensions")
+
+	// ErrNoResults is the error returned when there are no matching nodes.
+	ErrNoResults = errors.New("no results")
+
+	// ErrHasResults is the error returned when there should not be any
+	// matching nodes.
+	ErrHasResults = errors.New("has results")
+
+	// ErrNotVisible is the error returned when a non-visible node should be
+	// visible.
+	ErrNotVisible = errors.New("not visible")
+
+	// ErrVisible is the error returned when a visible node should be
+	// non-visible.
+	ErrVisible = errors.New("visible")
+
+	// ErrDisabled is the error returned when a disabled node should be
+	// enabled.
+	ErrDisabled = errors.New("disabled")
+
+	// ErrNotSelected is the error returned when a non-selected node should be
+	// selected.
+	ErrNotSelected = errors.New("not selected")
+
+	// ErrInvalidBoxModel is the error returned when the retrieved box model
+	// data is invalid.
+	ErrInvalidBoxModel = errors.New("invalid box model")
+)

examples/click/main.go

@@ -44,7 +44,7 @@ func click() cdp.Tasks {
 	return cdp.Tasks{
 		cdp.Navigate(`https://golang.org/pkg/time/`),
 		cdp.WaitVisible(`#footer`),
-		cdp.Click(`#pkg-overview`, cdp.ElementVisible),
+		cdp.Click(`#pkg-overview`, cdp.NodeVisible),
 		cdp.Sleep(150 * time.Second),
 	}
 }

examples/text/main.go

@@ -45,6 +45,6 @@ func main() {
 func text(res *string) cdp.Tasks {
 	return cdp.Tasks{
 		cdp.Navigate(`https://golang.org/pkg/time/`),
-		cdp.Text(`#pkg-overview`, res, cdp.ElementVisible, cdp.ByID),
+		cdp.Text(`#pkg-overview`, res, cdp.NodeVisible, cdp.ByID),
 	}
 }

handler.go

@@ -504,7 +504,7 @@ func (h *TargetHandler) pageEvent(ctxt context.Context, ev interface{}) {
 	defer h.pageWaitGroup.Done()
 
 	var id cdp.FrameID
-	var op FrameOp
+	var op frameOp
 
 	switch e := ev.(type) {
 	case *page.EventFrameNavigated:
@@ -569,7 +569,7 @@ func (h *TargetHandler) domEvent(ctxt context.Context, ev interface{}) {
 	}
 
 	var id cdp.NodeID
-	var op NodeOp
+	var op nodeOp
 
 	switch e := ev.(type) {
 	case *dom.EventSetChildNodes:

input.go

@@ -2,7 +2,6 @@ package chromedp
 
 import (
 	"context"
-	"errors"
 	"time"
 
 	"github.com/knq/chromedp/cdp"
@@ -11,11 +10,6 @@ import (
 	"github.com/knq/chromedp/kb"
 )
 
-// Error types.
-var (
-	ErrInvalidDimensions = errors.New("invalid box dimensions")
-)
-
 // MouseAction is a mouse action.
 func MouseAction(typ input.MouseType, x, y int64, opts ...MouseOption) Action {
 	me := input.DispatchMouseEvent(typ, x, y)

nav.go

@@ -82,6 +82,16 @@ func NavigateForward(ctxt context.Context, h cdp.Handler) error {
 	return page.NavigateToHistoryEntry(entries[i+1].ID).Do(ctxt, h)
 }
 
+// Stop stops all navigation and pending resource retrieval.
+func Stop() Action {
+	return page.StopLoading()
+}
+
+// Reload reloads the current page.
+func Reload() Action {
+	return page.Reload()
+}
+
 // CaptureScreenshot captures takes a full page screenshot.
 func CaptureScreenshot(res *[]byte) Action {
 	if res == nil {
@@ -113,16 +123,20 @@ func RemoveOnLoadScript(id page.ScriptIdentifier) Action {
 	return page.RemoveScriptToEvaluateOnLoad(id)
 }
 
-// Stop stops all navigation and pending resource retrieval.
+// Location retrieves the document location.
-func Stop() Action {
-	return page.StopLoading()
-}
-
-// Location retrieves the URL location.
 func Location(urlstr *string) Action {
 	if urlstr == nil {
 		panic("urlstr cannot be nil")
 	}
 
-	return EvaluateAsDevTools(`location.toString()`, urlstr)
+	return EvaluateAsDevTools(`document.location.toString()`, urlstr)
+}
+
+// Title retrieves the document title.
+func Title(title *string) Action {
+	if title == nil {
+		panic("title cannot be nil")
+	}
+
+	return EvaluateAsDevTools(`document.title`, title)
 }

pool.go

@@ -8,14 +8,6 @@ import (
 	"github.com/knq/chromedp/runner"
 )
 
-const (
-	// DefaultStartPort is the default start port number.
-	DefaultStartPort = 9000
-
-	// DefaultEndPort is the default end port number.
-	DefaultEndPort = 10000
-)
-
 // Pool manages a pool of running Chrome processes.
 type Pool struct {
 	// start is the start port.
@@ -35,8 +27,8 @@ func NewPool(opts ...PoolOption) (*Pool, error) {
 	var err error
 
 	p := &Pool{
-		start: DefaultStartPort,
+		start: DefaultPoolStartPort,
-		end:   DefaultEndPort,
+		end:   DefaultPoolEndPort,
 		res:   make(map[int]*Res),
 	}
 

query.go

@@ -12,17 +12,12 @@ import (
 
 	"github.com/disintegration/imaging"
 	"github.com/knq/chromedp/cdp"
+	"github.com/knq/chromedp/cdp/css"
 	"github.com/knq/chromedp/cdp/dom"
 	"github.com/knq/chromedp/cdp/page"
 )
 
-var (
+// Nodes retrieves the document nodes matching the selector.
-	// ErrInvalidBoxModel is the error returned when the retrieved box model is
-	// invalid.
-	ErrInvalidBoxModel = errors.New("invalid box model")
-)
-
-// Nodes retrieves the DOM nodes matching the selector.
 func Nodes(sel interface{}, nodes *[]*cdp.Node, opts ...QueryOption) Action {
 	if nodes == nil {
 		panic("nodes cannot be nil")
@@ -34,7 +29,7 @@ func Nodes(sel interface{}, nodes *[]*cdp.Node, opts ...QueryOption) Action {
 	}, opts...)
 }
 
-// NodeIDs returns the node IDs of the matching selector.
+// NodeIDs retrieves the node IDs matching the selector.
 func NodeIDs(sel interface{}, ids *[]cdp.NodeID, opts ...QueryOption) Action {
 	if ids == nil {
 		panic("nodes cannot be nil")
@@ -52,7 +47,7 @@ func NodeIDs(sel interface{}, ids *[]cdp.NodeID, opts ...QueryOption) Action {
 	}, opts...)
 }
 
-// Focus focuses the first element returned by the selector.
+// Focus focuses the first node matching the selector.
 func Focus(sel interface{}, opts ...QueryOption) Action {
 	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
 		if len(nodes) < 1 {
@@ -63,7 +58,7 @@ func Focus(sel interface{}, opts ...QueryOption) Action {
 	}, opts...)
 }
 
-// Blur unfocuses (blurs) the first element returned by the selector.
+// Blur unfocuses (blurs) the first node matching the selector.
 func Blur(sel interface{}, opts ...QueryOption) Action {
 	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
 		if len(nodes) < 1 {
@@ -75,14 +70,32 @@ func Blur(sel interface{}, opts ...QueryOption) Action {
 		if err != nil {
 			return err
 		}
+
 		if !res {
 			return fmt.Errorf("could not blur node %d", nodes[0].NodeID)
 		}
+
 		return nil
 	}, opts...)
 }
 
-// Text retrieves the text of the first element matching the selector.
+// Dimensions retrieves the box model dimensions for the first node matching
+// the selector.
+func Dimensions(sel interface{}, model **dom.BoxModel, opts ...QueryOption) Action {
+	if model == nil {
+		panic("model cannot be nil")
+	}
+	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
+		if len(nodes) < 1 {
+			return fmt.Errorf("selector `%s` did not return any nodes", sel)
+		}
+		var err error
+		*model, err = dom.GetBoxModel(nodes[0].NodeID).Do(ctxt, h)
+		return err
+	}, opts...)
+}
+
+// Text retrieves the visible text of the first node matching the selector.
 func Text(sel interface{}, text *string, opts ...QueryOption) Action {
 	if text == nil {
 		panic("text cannot be nil")
@@ -97,7 +110,7 @@ func Text(sel interface{}, text *string, opts ...QueryOption) Action {
 	}, opts...)
 }
 
-// Clear clears input and textarea fields of their values.
+// Clear clears the values of any input/textarea nodes matching the selector.
 func Clear(sel interface{}, opts ...QueryOption) Action {
 	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
 		if len(nodes) < 1 {
@@ -138,23 +151,7 @@ func Clear(sel interface{}, opts ...QueryOption) Action {
 	}, opts...)
 }
 
-// Dimensions retrieves the box model dimensions for the first node matching
+// Value retrieves the value of the first node matching the selector.
-// the specified selector.
-func Dimensions(sel interface{}, model **dom.BoxModel, opts ...QueryOption) Action {
-	if model == nil {
-		panic("model cannot be nil")
-	}
-	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
-		if len(nodes) < 1 {
-			return fmt.Errorf("selector `%s` did not return any nodes", sel)
-		}
-		var err error
-		*model, err = dom.GetBoxModel(nodes[0].NodeID).Do(ctxt, h)
-		return err
-	}, opts...)
-}
-
-// Value retrieves the value of an element.
 func Value(sel interface{}, value *string, opts ...QueryOption) Action {
 	if value == nil {
 		panic("value cannot be nil")
@@ -189,7 +186,7 @@ func SetValue(sel interface{}, value string, opts ...QueryOption) Action {
 	}, opts...)
 }
 
-// Attributes retrieves the attributes for the specified element.
+// Attributes retrieves the attributes for the first node matching the selector.
 func Attributes(sel interface{}, attributes *map[string]string, opts ...QueryOption) Action {
 	if attributes == nil {
 		panic("attributes cannot be nil")
@@ -215,19 +212,26 @@ func Attributes(sel interface{}, attributes *map[string]string, opts ...QueryOpt
 	}, opts...)
 }
 
-// SetAttributes sets the attributes for the specified element.
+// SetAttributes sets the attributes for the first node matching the selector.
 func SetAttributes(sel interface{}, attributes map[string]string, opts ...QueryOption) Action {
 	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
 		if len(nodes) < 1 {
 			return errors.New("expected at least one element")
 		}
 
-		return nil
+		attrs := make([]string, len(attributes)*2)
+		i := 0
+		for k, v := range attributes {
+			attrs[i], attrs[i+1] = k, v
+			i += 2
+		}
+
+		return dom.SetAttributesAsText(nodes[0].NodeID, strings.Join(attrs, " ")).Do(ctxt, h)
 	}, opts...)
 }
 
-// AttributeValue retrieves the name'd attribute value for the specified
+// AttributeValue retrieves the attribute value for the first node matching the
-// element.
+// selector.
 func AttributeValue(sel interface{}, name string, value *string, ok *bool, opts ...QueryOption) Action {
 	if value == nil {
 		panic("value cannot be nil")
@@ -260,7 +264,8 @@ func AttributeValue(sel interface{}, name string, value *string, ok *bool, opts
 	}, opts...)
 }
 
-// SetAttributeValue sets an element's attribute with name to value.
+// SetAttributeValue sets the attribute with name to value on the first node
+// matching the selector.
 func SetAttributeValue(sel interface{}, name, value string, opts ...QueryOption) Action {
 	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
 		if len(nodes) < 1 {
@@ -271,7 +276,8 @@ func SetAttributeValue(sel interface{}, name, value string, opts ...QueryOption)
 	}, opts...)
 }
 
-// RemoveAttribute removes an element's attribute with name.
+// RemoveAttribute removes the attribute with name from the first node matching
+// the selector.
 func RemoveAttribute(sel interface{}, name string, opts ...QueryOption) Action {
 	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
 		if len(nodes) < 1 {
@@ -282,7 +288,7 @@ func RemoveAttribute(sel interface{}, name string, opts ...QueryOption) Action {
 	}, opts...)
 }
 
-// Click sends a click to the first element returned by the selector.
+// Click sends a mouse click event to the first node matching the selector.
 func Click(sel interface{}, opts ...QueryOption) Action {
 	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
 		if len(nodes) < 1 {
@@ -290,10 +296,11 @@ func Click(sel interface{}, opts ...QueryOption) Action {
 		}
 
 		return MouseClickNode(nodes[0]).Do(ctxt, h)
-	}, append(opts, ElementVisible)...)
+	}, append(opts, NodeVisible)...)
 }
 
-// DoubleClick does a double click on the first element returned by selector.
+// DoubleClick sends a mouse double click event to the first node matching the
+// selector.
 func DoubleClick(sel interface{}, opts ...QueryOption) Action {
 	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
 		if len(nodes) < 1 {
@@ -301,34 +308,21 @@ func DoubleClick(sel interface{}, opts ...QueryOption) Action {
 		}
 
 		return MouseClickNode(nodes[0], ClickCount(2)).Do(ctxt, h)
-	}, append(opts, ElementVisible)...)
+	}, append(opts, NodeVisible)...)
 }
 
-// NOTE: temporarily disabling this until a proper unit test can be written.
+// SendKeys synthesizes the key up, char, and down events as needed for the
-//
+// runes in v, sending them to the first node matching the selector.
-// Hover hovers (moves) the mouse over the first element returned by the
-// selector.
-//func Hover(sel interface{}, opts ...QueryOption) Action {
-//	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
-//		if len(nodes) < 1 {
-//			return fmt.Errorf("selector `%s` did not return any nodes", sel)
-//		}
-//
-//		return MouseClickNode(nodes[0], ButtonNone).Do(ctxt, h)
-//	}, append(opts, ElementVisible)...)
-//}
-
-// SendKeys sends keys to the first element returned by selector.
 func SendKeys(sel interface{}, v string, opts ...QueryOption) Action {
 	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
 		if len(nodes) < 1 {
 			return fmt.Errorf("selector `%s` did not return any nodes", sel)
 		}
 		return KeyActionNode(nodes[0], v).Do(ctxt, h)
-	}, append(opts, ElementVisible)...)
+	}, append(opts, NodeVisible)...)
 }
 
-// Screenshot takes a screenshot of the first element matching the selector.
+// Screenshot takes a screenshot of the first node matching the selector.
 func Screenshot(sel interface{}, picbuf *[]byte, opts ...QueryOption) Action {
 	if picbuf == nil {
 		panic("picbuf cannot be nil")
@@ -387,11 +381,11 @@ func Screenshot(sel interface{}, picbuf *[]byte, opts ...QueryOption) Action {
 		*picbuf = croppedBuf.Bytes()
 
 		return nil
-	}, append(opts, ElementVisible)...)
+	}, append(opts, NodeVisible)...)
 }
 
-// Submit is an action that submits whatever form the first element matching
+// Submit is an action that submits the form of the first node matching the
-// the selector belongs to.
+// selector belongs to.
 func Submit(sel interface{}, opts ...QueryOption) Action {
 	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
 		if len(nodes) < 1 {
@@ -412,7 +406,7 @@ func Submit(sel interface{}, opts ...QueryOption) Action {
 	}, opts...)
 }
 
-// Reset is an action that resets whatever form the first element matching the
+// Reset is an action that resets the form of the first node matching the
 // selector belongs to.
 func Reset(sel interface{}, opts ...QueryOption) Action {
 	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
@@ -434,84 +428,51 @@ func Reset(sel interface{}, opts ...QueryOption) Action {
 	}, opts...)
 }
 
-const (
+// ComputedStyle retrieves the computed style of the first node matching the selector.
-	// textJS is a javascript snippet that returns the concatenated textContent
+func ComputedStyle(sel interface{}, style *[]*css.ComputedProperty, opts ...QueryOption) Action {
-	// of all visible (ie, offsetParent !== null) children.
+	if style == nil {
-	textJS = `(function(a) {
+		panic("style cannot be nil")
-		var s = '';
-		for (var i = 0; i < a.length; i++) {
-			if (a[i].offsetParent !== null) {
-				s += a[i].textContent;
 	}
+
+	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
+		if len(nodes) < 1 {
+			return fmt.Errorf("selector `%s` did not return any nodes", sel)
 		}
-		return s;
-	})($x("%s/node()"))`
 
-	// blurJS is a javscript snippet that blurs the specified element.
+		computed, err := css.GetComputedStyleForNode(nodes[0].NodeID).Do(ctxt, h)
-	blurJS = `(function(a) {
+		if err != nil {
-		a[0].blur();
+			return err
-		return true;
-	})($x('%s'))`
-
-	// scrollJS is a javascript snippet that scrolls the window to the
-	// specified x, y coordinates and then returns the actual window x/y after
-	// execution.
-	scrollJS = `(function(x, y) {
-		window.scrollTo(x, y);
-		return [window.scrollX, window.scrollY];
-	})(%d, %d)`
-
-	// submitJS is a javascript snippet that will call the containing form's
-	// submit function, returning true or false if the call was successful.
-	submitJS = `(function(a) {
-		if (a[0].nodeName === 'FORM') {
-			a[0].submit();
-			return true;
-		} else if (a[0].form !== null) {
-			a[0].form.submit();
-			return true;
 		}
-		return false;
-	})($x('%s'))`
 
-	// resetJS is a javascript snippet that will call the containing form's
+		*style = computed
-	// reset function, returning true or false if the call was successful.
+
-	resetJS = `(function(a) {
+		return nil
-		if (a[0].nodeName === 'FORM') {
+	}, opts...)
-			a[0].reset();
+}
-			return true;
+
-		} else if (a[0].form !== null) {
+// MatchedStyle retrieves the matched style information for the first node
-			a[0].form.reset();
+// matching the selector.
-			return true;
+func MatchedStyle(sel interface{}, style **css.GetMatchedStylesForNodeReturns, opts ...QueryOption) Action {
+	if style == nil {
+		panic("style cannot be nil")
 	}
-		return false;
-	})($x('%s'))`
 
-	// valueJS is a javascript snippet that returns the value of a specified
+	return QueryAfter(sel, func(ctxt context.Context, h cdp.Handler, nodes ...*cdp.Node) error {
-	// node.
+		if len(nodes) < 1 {
-	valueJS = `(function(a) {
+			return fmt.Errorf("selector `%s` did not return any nodes", sel)
-		return a[0].value;
+		}
-	})($x('%s'))`
 
-	// setValueJS is a javascript snippet that sets the value of the specified
+		var err error
-	// node, and returns the value.
+		ret := &css.GetMatchedStylesForNodeReturns{}
-	setValueJS = `(function(a, val) {
+		ret.InlineStyle, ret.AttributesStyle, ret.MatchedCSSRules,
-		return a[0].value = val;
+			ret.PseudoElements, ret.Inherited, ret.CSSKeyframesRules,
-	})($x('%s'), '%s')`
+			err = css.GetMatchedStylesForNode(nodes[0].NodeID).Do(ctxt, h)
-)
+		if err != nil {
+			return err
+		}
 
-/*
+		*style = ret
 
-Title
+		return nil
-SetTitle
+	}, opts...)
-OuterHTML
+}
-SetOuterHTML
-
-NodeName -- ?
-
-Style(Matched)
-Style(Computed)
-SetStyle
-GetStyle(Inline)
-
-*/

sel.go

@@ -2,14 +2,12 @@ package chromedp
 
 import (
 	"context"
-	"errors"
 	"fmt"
 	"strings"
 	"sync"
 	"time"
 
 	"github.com/knq/chromedp/cdp"
-	"github.com/knq/chromedp/cdp/css"
 	"github.com/knq/chromedp/cdp/dom"
 )
 
@@ -24,16 +22,6 @@ tagname
 
 */
 
-// Error types.
-var (
-	ErrNoResults   = errors.New("no results")
-	ErrHasResults  = errors.New("has results")
-	ErrNotVisible  = errors.New("not visible")
-	ErrVisible     = errors.New("visible")
-	ErrDisabled    = errors.New("disabled")
-	ErrNotSelected = errors.New("not selected")
-)
-
 // Selector holds information pertaining to an element query select action.
 type Selector struct {
 	sel   interface{}
@@ -61,7 +49,7 @@ func Query(sel interface{}, opts ...QueryOption) Action {
 	}
 
 	if s.wait == nil {
-		ElementReady(s)
+		NodeReady(s)
 	}
 
 	return s
@@ -294,13 +282,13 @@ func WaitFunc(wait func(context.Context, cdp.Handler, *cdp.Node, ...cdp.NodeID)
 	}
 }
 
-// ElementReady is a query option to wait until the element is ready.
+// NodeReady is a query option to wait until the element is ready.
-func ElementReady(s *Selector) {
+func NodeReady(s *Selector) {
 	WaitFunc(s.waitReady(nil))(s)
 }
 
-// ElementVisible is a query option to wait until the element is visible.
+// NodeVisible is a query option to wait until the element is visible.
-func ElementVisible(s *Selector) {
+func NodeVisible(s *Selector) {
 	WaitFunc(s.waitReady(func(ctxt context.Context, h cdp.Handler, n *cdp.Node) error {
 		var err error
 
@@ -327,8 +315,8 @@ func ElementVisible(s *Selector) {
 	}))(s)
 }
 
-// ElementNotVisible is a query option to wait until the element is not visible.
+// NodeNotVisible is a query option to wait until the element is not visible.
-func ElementNotVisible(s *Selector) {
+func NodeNotVisible(s *Selector) {
 	WaitFunc(s.waitReady(func(ctxt context.Context, h cdp.Handler, n *cdp.Node) error {
 		var err error
 
@@ -355,105 +343,8 @@ func ElementNotVisible(s *Selector) {
 	}))(s)
 }
 
-// ElementVisibleOld is a query option to wait until the element is visible.
+// NodeEnabled is a query option to wait until the element is enabled.
-//
+func NodeEnabled(s *Selector) {
-// This is the old, complicated, implementation (deprecated).
-func ElementVisibleOld(s *Selector) {
-	WaitFunc(s.waitReady(func(ctxt context.Context, h cdp.Handler, n *cdp.Node) error {
-		var err error
-
-		// check node has box model
-		_, err = dom.GetBoxModel(n.NodeID).Do(ctxt, h)
-		if err != nil {
-			return err
-		}
-
-		// check if any of the parents are not visible ...
-		var hidden bool
-		for ; n.Parent != nil; n = n.Parent {
-			// get style
-			style, err := css.GetComputedStyleForNode(n.NodeID).Do(ctxt, h)
-			if err != nil {
-				return err
-			}
-
-			// check if hidden
-			for _, c := range style {
-				switch c.Name {
-				case "display":
-					//log.Printf("%d >>>> %s=%s", n.NodeID, c.Name, c.Value)
-					hidden = c.Value == "none"
-
-				case "visibility":
-					//log.Printf("%d >>>> %s=%s", n.NodeID, c.Name, c.Value)
-					hidden = c.Value != "visible"
-
-				case "hidden":
-					//log.Printf("%d >>>> %s=%s", n.NodeID, c.Name, c.Value)
-					hidden = true
-				}
-
-				if hidden {
-					return ErrNotVisible
-				}
-			}
-		}
-
-		return nil
-	}))(s)
-}
-
-// ElementNotVisibleOld is a query option to wait until the element is not
-// visible.
-//
-// This is the old, complicated, implementation (deprecated).
-func ElementNotVisibleOld(s *Selector) {
-	WaitFunc(s.waitReady(func(ctxt context.Context, h cdp.Handler, n *cdp.Node) error {
-		var err error
-
-		// check node has box model
-		_, err = dom.GetBoxModel(n.NodeID).Do(ctxt, h)
-		if err != nil {
-			return nil
-		}
-
-		// check if any of the parents are not visible ...
-		var hidden bool
-		for ; n.Parent != nil; n = n.Parent {
-			// get style
-			style, err := css.GetComputedStyleForNode(n.NodeID).Do(ctxt, h)
-			if err != nil {
-				return err
-			}
-
-			// check if hidden
-			for _, c := range style {
-				switch c.Name {
-				case "display":
-					//log.Printf("%d >>>> %s=%s", n.NodeID, c.Name, c.Value)
-					hidden = c.Value == "none"
-
-				case "visibility":
-					//log.Printf("%d >>>> %s=%s", n.NodeID, c.Name, c.Value)
-					hidden = c.Value != "visible"
-
-				case "hidden":
-					//log.Printf("%d >>>> %s=%s", n.NodeID, c.Name, c.Value)
-					hidden = true
-				}
-
-				if hidden {
-					return nil
-				}
-			}
-		}
-
-		return ErrVisible
-	}))(s)
-}
-
-// ElementEnabled is a query option to wait until the element is enabled.
-func ElementEnabled(s *Selector) {
 	WaitFunc(s.waitReady(func(ctxt context.Context, h cdp.Handler, n *cdp.Node) error {
 		n.RLock()
 		defer n.RUnlock()
@@ -468,8 +359,8 @@ func ElementEnabled(s *Selector) {
 	}))(s)
 }
 
-// ElementSelected is a query option to wait until the element is selected.
+// NodeSelected is a query option to wait until the element is selected.
-func ElementSelected(s *Selector) {
+func NodeSelected(s *Selector) {
 	WaitFunc(s.waitReady(func(ctxt context.Context, h cdp.Handler, n *cdp.Node) error {
 		n.RLock()
 		defer n.RUnlock()
@@ -484,9 +375,9 @@ func ElementSelected(s *Selector) {
 	}))(s)
 }
 
-// ElementNotPresent is a query option to wait until no elements match are
+// NodeNotPresent is a query option to wait until no elements match are
 // present matching the selector.
-func ElementNotPresent(s *Selector) {
+func NodeNotPresent(s *Selector) {
 	s.exp = 0
 	WaitFunc(func(ctxt context.Context, h cdp.Handler, n *cdp.Node, ids ...cdp.NodeID) ([]*cdp.Node, error) {
 		if len(ids) != 0 {
@@ -519,34 +410,26 @@ func WaitReady(sel interface{}, opts ...QueryOption) Action {
 
 // WaitVisible waits until the selected element is visible.
 func WaitVisible(sel interface{}, opts ...QueryOption) Action {
-	return Query(sel, append(opts, ElementVisible)...)
+	return Query(sel, append(opts, NodeVisible)...)
 }
 
 // WaitNotVisible waits until the selected element is not visible.
 func WaitNotVisible(sel interface{}, opts ...QueryOption) Action {
-	return Query(sel, append(opts, ElementNotVisible)...)
+	return Query(sel, append(opts, NodeNotVisible)...)
 }
 
 // WaitEnabled waits until the selected element is enabled (does not have
 // attribute 'disabled').
 func WaitEnabled(sel interface{}, opts ...QueryOption) Action {
-	return Query(sel, append(opts, ElementEnabled)...)
+	return Query(sel, append(opts, NodeEnabled)...)
 }
 
 // WaitSelected waits until the element is selected (has attribute 'selected').
 func WaitSelected(sel interface{}, opts ...QueryOption) Action {
-	return Query(sel, append(opts, ElementSelected)...)
+	return Query(sel, append(opts, NodeSelected)...)
 }
 
 // WaitNotPresent waits until no elements match the specified selector.
 func WaitNotPresent(sel interface{}, opts ...QueryOption) Action {
-	return Query(sel, append(opts, ElementNotPresent)...)
+	return Query(sel, append(opts, NodeNotPresent)...)
 }
-
-const (
-	// visibleJS is a javascript snippet that returns true or false depending
-	// on if the specified node's offsetParent is not null.
-	visibleJS = `(function(a) {
-		return a[0].offsetParent !== null
-	})($x('%s'))`
-)

util.go

@@ -15,11 +15,87 @@ const (
 	// DefaultCheckDuration is the default time to sleep between a check.
 	DefaultCheckDuration = 50 * time.Millisecond
 
+	// DefaultPoolStartPort is the default start port number.
+	DefaultPoolStartPort = 9000
+
+	// DefaultPoolEndPort is the default end port number.
+	DefaultPoolEndPort = 10000
+
 	// EmptyFrameID is the "non-existent" (ie current) frame.
 	EmptyFrameID cdp.FrameID = cdp.FrameID("")
 
 	// EmptyNodeID is the "non-existent" node id.
 	EmptyNodeID cdp.NodeID = cdp.NodeID(0)
+
+	// textJS is a javascript snippet that returns the concatenated textContent
+	// of all visible (ie, offsetParent !== null) children.
+	textJS = `(function(a) {
+		var s = '';
+		for (var i = 0; i < a.length; i++) {
+			if (a[i].offsetParent !== null) {
+				s += a[i].textContent;
+			}
+		}
+		return s;
+	})($x("%s/node()"))`
+
+	// blurJS is a javscript snippet that blurs the specified element.
+	blurJS = `(function(a) {
+		a[0].blur();
+		return true;
+	})($x('%s'))`
+
+	// scrollJS is a javascript snippet that scrolls the window to the
+	// specified x, y coordinates and then returns the actual window x/y after
+	// execution.
+	scrollJS = `(function(x, y) {
+		window.scrollTo(x, y);
+		return [window.scrollX, window.scrollY];
+	})(%d, %d)`
+
+	// submitJS is a javascript snippet that will call the containing form's
+	// submit function, returning true or false if the call was successful.
+	submitJS = `(function(a) {
+		if (a[0].nodeName === 'FORM') {
+			a[0].submit();
+			return true;
+		} else if (a[0].form !== null) {
+			a[0].form.submit();
+			return true;
+		}
+		return false;
+	})($x('%s'))`
+
+	// resetJS is a javascript snippet that will call the containing form's
+	// reset function, returning true or false if the call was successful.
+	resetJS = `(function(a) {
+		if (a[0].nodeName === 'FORM') {
+			a[0].reset();
+			return true;
+		} else if (a[0].form !== null) {
+			a[0].form.reset();
+			return true;
+		}
+		return false;
+	})($x('%s'))`
+
+	// valueJS is a javascript snippet that returns the value of a specified
+	// node.
+	valueJS = `(function(a) {
+		return a[0].value;
+	})($x('%s'))`
+
+	// setValueJS is a javascript snippet that sets the value of the specified
+	// node, and returns the value.
+	setValueJS = `(function(a, val) {
+		return a[0].value = val;
+	})($x('%s'), '%s')`
+
+	// visibleJS is a javascript snippet that returns true or false depending
+	// on if the specified node's offsetParent is not null.
+	visibleJS = `(function(a) {
+		return a[0].offsetParent !== null
+	})($x('%s'))`
 )
 
 // UnmarshalMessage unmarshals the message result or params.
@@ -27,8 +103,8 @@ func UnmarshalMessage(msg *cdp.Message) (interface{}, error) {
 	return util.UnmarshalMessage(msg)
 }
 
-// FrameOp is a frame manipulation operation.
+// frameOp is a frame manipulation operation.
-type FrameOp func(*cdp.Frame)
+type frameOp func(*cdp.Frame)
 
 /*func domContentEventFired(f *cdp.Frame) {
 }
@@ -36,7 +112,7 @@ type FrameOp func(*cdp.Frame)
 func loadEventFired(f *cdp.Frame) {
 }*/
 
-func frameAttached(id cdp.FrameID) FrameOp {
+func frameAttached(id cdp.FrameID) frameOp {
 	return func(f *cdp.Frame) {
 		f.ParentID = id
 		setFrameState(f, cdp.FrameAttached)
@@ -82,8 +158,8 @@ func clearFrameState(f *cdp.Frame, fs cdp.FrameState) {
 	f.State &^= fs
 }
 
-// NodeOp is a node manipulation operation.
+// nodeOp is a node manipulation operation.
-type NodeOp func(*cdp.Node)
+type nodeOp func(*cdp.Node)
 
 func walk(m map[cdp.NodeID]*cdp.Node, n *cdp.Node) {
 	m[n.NodeID] = n
@@ -117,14 +193,14 @@ func walk(m map[cdp.NodeID]*cdp.Node, n *cdp.Node) {
 	}
 }
 
-func setChildNodes(m map[cdp.NodeID]*cdp.Node, nodes []*cdp.Node) NodeOp {
+func setChildNodes(m map[cdp.NodeID]*cdp.Node, nodes []*cdp.Node) nodeOp {
 	return func(n *cdp.Node) {
 		n.Children = nodes
 		walk(m, n)
 	}
 }
 
-func attributeModified(name, value string) NodeOp {
+func attributeModified(name, value string) nodeOp {
 	return func(n *cdp.Node) {
 		var found bool
 
@@ -145,7 +221,7 @@ func attributeModified(name, value string) NodeOp {
 	}
 }
 
-func attributeRemoved(name string) NodeOp {
+func attributeRemoved(name string) nodeOp {
 	return func(n *cdp.Node) {
 		var a []string
 		for i := 0; i < len(n.Attributes); i += 2 {
@@ -158,66 +234,66 @@ func attributeRemoved(name string) NodeOp {
 	}
 }
 
-func inlineStyleInvalidated(ids []cdp.NodeID) NodeOp {
+func inlineStyleInvalidated(ids []cdp.NodeID) nodeOp {
 	return func(n *cdp.Node) {
 	}
 }
 
-func characterDataModified(characterData string) NodeOp {
+func characterDataModified(characterData string) nodeOp {
 	return func(n *cdp.Node) {
 		n.Value = characterData
 	}
 }
 
-func childNodeCountUpdated(count int64) NodeOp {
+func childNodeCountUpdated(count int64) nodeOp {
 	return func(n *cdp.Node) {
 		n.ChildNodeCount = count
 	}
 }
 
-func childNodeInserted(m map[cdp.NodeID]*cdp.Node, prevID cdp.NodeID, c *cdp.Node) NodeOp {
+func childNodeInserted(m map[cdp.NodeID]*cdp.Node, prevID cdp.NodeID, c *cdp.Node) nodeOp {
 	return func(n *cdp.Node) {
 		n.Children = insertNode(n.Children, prevID, c)
 		walk(m, n)
 	}
 }
 
-func childNodeRemoved(m map[cdp.NodeID]*cdp.Node, id cdp.NodeID) NodeOp {
+func childNodeRemoved(m map[cdp.NodeID]*cdp.Node, id cdp.NodeID) nodeOp {
 	return func(n *cdp.Node) {
 		n.Children = removeNode(n.Children, id)
 		//delete(m, id)
 	}
 }
 
-func shadowRootPushed(m map[cdp.NodeID]*cdp.Node, c *cdp.Node) NodeOp {
+func shadowRootPushed(m map[cdp.NodeID]*cdp.Node, c *cdp.Node) nodeOp {
 	return func(n *cdp.Node) {
 		n.ShadowRoots = append(n.ShadowRoots, c)
 		walk(m, n)
 	}
 }
 
-func shadowRootPopped(m map[cdp.NodeID]*cdp.Node, id cdp.NodeID) NodeOp {
+func shadowRootPopped(m map[cdp.NodeID]*cdp.Node, id cdp.NodeID) nodeOp {
 	return func(n *cdp.Node) {
 		n.ShadowRoots = removeNode(n.ShadowRoots, id)
 		//delete(m, id)
 	}
 }
 
-func pseudoElementAdded(m map[cdp.NodeID]*cdp.Node, c *cdp.Node) NodeOp {
+func pseudoElementAdded(m map[cdp.NodeID]*cdp.Node, c *cdp.Node) nodeOp {
 	return func(n *cdp.Node) {
 		n.PseudoElements = append(n.PseudoElements, c)
 		walk(m, n)
 	}
 }
 
-func pseudoElementRemoved(m map[cdp.NodeID]*cdp.Node, id cdp.NodeID) NodeOp {
+func pseudoElementRemoved(m map[cdp.NodeID]*cdp.Node, id cdp.NodeID) nodeOp {
 	return func(n *cdp.Node) {
 		n.PseudoElements = removeNode(n.PseudoElements, id)
 		//delete(m, id)
 	}
 }
 
-func distributedNodesUpdated(nodes []*cdp.BackendNode) NodeOp {
+func distributedNodesUpdated(nodes []*cdp.BackendNode) nodeOp {
 	return func(n *cdp.Node) {
 		n.DistributedNodes = nodes
 	}