There is some risk to this change. The first is that I made a mistake. The
other is that one of the APIs that doesn't currently return an error changes
in the future.
CDP currently assumes that if we get a page-related notification (like a
request interception, or page lifecycle event), then we must have a session
and page.
But, Target.detachFromTarget can remove the session from the BrowserContext
while still having the page run (I wonder if we should stop the page at this
point??). So, remove these assumptions and make sure we have a page/session
in the handling of page events.
chromedb doesn't support duplicate header names. Although servers _will_ send
this (e.g. Cache-Control: public\r\nCache-Control: max-age=60\r\n), Chrome
seems to join them with a "\n". So we do the same.
A note on curl_easy_nextheader, which this code ultimately uses to iterate
and collect the headers. The documentation says:
Applications must copy the data if they want it to survive subsequent API
calls or the life-time of the easy handle.
As-is, I'd understand this to mean that a given header name/value is only
valid until any API call, including another call to curl_easy_nextheader. So,
from this comment, we _should_ be duping the name/value. But we don't. Why?
Because, despite the note in the documentation, this doesn't appear to be how
it actually works, nor does it really make sense. If it's just a linked list,
there's no reason curl_easy_nextheader should invalidate previous results. I'm
guessing this is just a general lack of guarantee libcurl is willing to make re
lifetimes.
https://github.com/lightpanda-io/browser/issues/966
Add response_data event, CDP now captures the full body so that it can respond
to the Network.getResponseBody. This isn't memory efficient, but I don't see
another way to do it. At least this way, it's only capturing/storing every
response body when (a) CDP is used and (b) Network.enabled is called. That is,
as opposed to baking this into Http/Client.zig, which would force the memory
consumption for all use-cases.
There's arguably some optimizations we could make for XHR requests, which also
dupe/own the response. As of now, the response is dupe'd separately for CDP
and XHR.
With networking enabled, CDP listens to this event and emits a
`Network.loadingFinished` event. This is event is used by puppeteer to know that
details about the response (i.e. the body) can be queries.
Added dummy handling for the Network.getResponseBody message. Returns an
empty body. Needed because we emit the loadingFinished event which signals
to drivers that they can ask for the body.
Stream (to json) the Transfer as a request and response object in the various
network interception-related events (e.g. Network.responseReceived).
Add a page.request_intercepted boolean flag for CDP to signal the page that
requests have been intercepted, allowing Page.wait to prioritize intercept
handling (or, at least, not block it).
On client.request(req) we now immediately wrap the request into a Transfer. This
results in less copying of the Request object. It also makes the transfer.uri
available, so CDP no longer needs to std.Uri(request.url) anymore.
The main advantage is that it's easier to manage resources. There was a use-
after free before due to the sensitive nature of the tranfer's lifetime. There
were also corner cases where some resources might not be freed. This is
hopefully fixed with the lifetime of Transfer being extended.
go-rod appears to stop processing when it receives an error, such as
UnknownMethod. Added placeholder handlers for Network.setUserAgentOverride and
Page.stopLoading.
Setting a custom user agent is something still being discussed, so no-oping it
seems reasonable. And, due to the currently synchronous nature of the initial
page load, no-oping stopLoading also seems reasonable.
https://github.com/lightpanda-io/browser/issues/867
This is one of the ways that puppeteer knows that navigation happened
and is needed to support `waitForNavigation` which compares the
existing loader-id with the new one, so it has to change.
Also, fix a crash that could happen if CDP disconnects while
connections are being aborted.
CDP translate this into a Network.loadingFailed. This is necessary to make sure
every Network.requestWillBeSent is paired with either a Network.loadingFailed
or a Network.responseReceived.
- Add 2 internal notifications
1 - http_request_start
2 - http_request_complete
- When Network.enable CDP message is received, browser context registers for
these 2 events (when Network.disable is called, it unregisters)
- On http_request_start, CDP will emit a Network.requestWillBeSent message.
This _does not_ include all the fields, but what we have appears to be enough
for puppeteer.waitForNetworkIdle.
- On http_request_complete, CDP will emit a Network.responseReceived message.
This _does not_ include all the fields, bu what we have appears to be enough
for puppeteer.waitForNetworkIdle.
We currently don't emit any other new events, including any network-specific
lifecycleEvent (i.e. Chrome will emit an networkIdle and networkAlmostIdle).
To support this, the following other things were done:
- CDP now has a `notification_arena` which is re-used between browser contexts.
Normally, CDP code runs based on a "cmd" which has its own message_arena, but
these notifications happen out-of-band, so we needed a new arena which is
valid for handling 1 notification.
- HTTP Client is notification-aware. The SessionState no longer includes the
*http.Client directly. It instead includes an http.RequestFactory which is
the combination fo the client + a specific configuration (i.e. *Notification).
This ensures that all requests made from that factory have the same settings.
- However, despite the above, _some_ requests do not appear to emit CDP events,
such as loading a <script src="X">. So the page still deals directly with the
*http.Client.
- Playwright and Puppeteer (but Playwright in particular) are very sensitive to
event ordering. These new events have introduced additional sensitivity.
The result sent to Page.navigate had to be moved to inside the navigate event
handler, which meant passing some cdp-specific data (the input.id) into the
NavigateOpts. This is the only way I found to keep both happy - the sequence
of events is closer (but still pretty far) from what Chrome does.
This expands on the existing CDP node work used in DOM.search. It introduces
a node registry to track all nodes returned to the client and give lookups to
get a node from a Id or a *parser.node.
Eventually, the goal is to have the Registry emit the DOM.setChildNodes event
whenever necessary, as well as support many of the missing DOM actions.
Added tests to existing search handlers. Reworked search a little bit to avoid
some unnecessary allocations and to hook it into the registry.
The generated Node is currently incomplete. The parentId is missing, the
children are missing. Also, we still need to associate the v8 ObjectId to the
node.
Finally, I moved all action handlers into a nested "domain" folder.
