feat: expose raw devtools protocol connection
This patch introduces `target.createCDPSession` method that
allows directly communicating with the target over the
Chrome DevTools Protocol.
Fixes#31.
In Blink, frames don't necesserily have execution context all the time.
DevTools Protocol precisely reports this situation, which results in
Puppeteer's frame.executionContext() being null occasionally.
However, from puppeteer point of view every frame will have at least a
default executions context, sooner or later:
- frame's execution context might be created naturally to run frame's
javascript
- if frame has no javascript, devtools protocol will issue execution
context creation
This patch builds up on this assumption and makes frame.executionContext()
to be a promise.
As a result, all the evaluations await for the execution context to be created first.
Fixes#827, #1325
BREAKING CHANGE: this patch changes frame.executionContext() method to return a promise.
To migrate onto a new behavior, await the context first before using it.
Currently, JSHandle.jsonValue() is implemented as in-page JSON.stringify
call and consequent JSON.parse in node. This approach proved to be
unfortunate for automation purposes: if page author overrode the
Object.prototype.toJSON method, then it's harder for puppeteer to
interact with the page.
This patch switches JSHandle.jsonValue to use protocol serialization
that ignores toJSON property. THis also changes the `page.evaluate`
behavior since it is based on JSHandle.jsonValue().
Fixes#1003.
BREAKING CHANGE:
`page.evaluate` no longer calls toJSON when generating return value.
For the old behavior, do JSON.parse/JSON.stringify manually:
```js
const json = JSON.parse(await page.evaluate(() => JSON.stringify(obj)));
```
This patch introduces `Page.queryObjects` and
`ExecutionContext.queryObjects` methods to query JavaScript heap
for objects with a certain prototype.
Fixes#304.
This patch:
- updates JSHandle.toString to make a nicer description for primitives
- excludes JSHandle.toString from documentation to avoid its abuse
References #382
This patch:
- adds `ElementHandle.boundingBox()` method to get bounding box of element relative
to the page
- adds `ElementHandle.screenshot()` method to capture a screenshot of an element
This patch starts using typescript to lint JSDoc annotations.
Note: this uses typescript's bleeding edge. We should migrate to stable once
it has all the necessary bugfixes.
References #65.
This patch:
- introduces ExecutionContext class that incapsulates javascript
execution context. An examples of execution contexts are workers and
frames
- introduces JSHandle that holds a references to the javascript
object in ExecutionContext
- inherits ElementHandle from JSHandle
Fixes#382.
