chromedp/actions.go
Daniel Martí 335d22d376 all: simplify some error variables
There's no need to put the error variables in a larger scope, nor define
them earlier than necessary. If anything, it makes the code harder to
follow, such as figuring out when nil errors are returned.
2017-12-18 10:51:37 +07:00

59 lines
1.6 KiB
Go

package chromedp
import (
"context"
"time"
"github.com/knq/chromedp/cdp"
)
// Action is the common interface for an action that will be executed against a
// context and frame handler.
type Action interface {
// Do executes the action using the provided context and frame handler.
Do(context.Context, cdp.Handler) error
}
// ActionFunc is a adapter to allow the use of ordinary func's as an Action.
type ActionFunc func(context.Context, cdp.Handler) error
// Do executes the func f using the provided context and frame handler.
func (f ActionFunc) Do(ctxt context.Context, h cdp.Handler) error {
return f(ctxt, h)
}
// Tasks is a sequential list of Actions that can be used as a single Action.
type Tasks []Action
// Do executes the list of Actions sequentially, using the provided context and
// frame handler.
func (t Tasks) Do(ctxt context.Context, h cdp.Handler) error {
// TODO: put individual task timeouts from context here
for _, a := range t {
// ctxt, cancel = context.WithTimeout(ctxt, timeout)
// defer cancel()
if err := a.Do(ctxt, h); err != nil {
return err
}
}
return nil
}
// Sleep is an empty action that calls time.Sleep with the specified duration.
//
// Note: this is a temporary action definition for convenience, and will likely
// be marked for deprecation in the future, after the remaining Actions have
// been able to be written/tested.
func Sleep(d time.Duration) Action {
return ActionFunc(func(ctxt context.Context, h cdp.Handler) error {
select {
case <-time.After(d):
case <-ctxt.Done():
return ctxt.Err()
}
return nil
})
}