- Intercept CSSOM modifications and recalculate overridden css text.
- When css text does not change, use "backwards reference" similar
to node references.
- Set 'Cache-Control: no-cache' for resources that could be overridden.
- Switch from html to json ml format.
- Allow node reuse between snapshots with `[nSnapshotsBefore, nodeWithIndexM]`.
- Service worker now lazily serializes snapshot chunks into a single html.
This decreases total snapshot size on random scripts ~10x.
This also decreases snapshot collecting time on mostly static pages to ~0.3ms.
Unfortunate downside for now is that we have to intercept
`Element.prototype.attachShadow` to invalidate nodes. This
also temporary breaks scroll restoration. Needs more research.
- Move service worker under /snapshot/ instead of /.
- Fix stylesheet base uri bug, where we inherited the wrong base url.
- Introduce TraceServer and routes there, split the actual routes
between snapshot, ui and action previews.
This introduces an http server that serves our frontend and our snapshots. There is more work to untangle the big server into a few modules.
This change allows us:
- Maybe eventually serve the trace viewer as a web page.
- Rely on browser caches for fast snapshot rendering. This PR also adds "snapshot on hover" feature, subject to change.
feat(trace viewer): Extending existing NetworkTab view
Currently the network tab contains a limited amount of information on the resources that were loaded in the browser. This change proposes extending the details displayed for each resource, to include:
- HTTP method,
- Full url,
- Easily visible response content type,
- Request headers,
- Request & response bodies.
Such level of information could help quickly understand what happened in the application, when it was communicating with backend services. This can help debug tests quicker to figure out why they are failing.
This implementation still needs some clean up & tests improvement, but I wanted to propose such changes and gather your feedback before going too far.
- Instead of capturing snapshots on demand, we now stream them
from each frame every 100ms.
- Certain actions can also force snapshots at particular moment using
"checkpoints".
- Trace viewer is able to show the page snapshot at a particular
timestamp, or using a "checkpoint" snapshot.
- Small optimization to not process stylesheets if CSSOM was not used.
There still is a lot of room for improvement.
fix(trace viewer): updating default traceStorageDir value
When `npx playwright show-trace <tracePath>` command is executed, without providing the `resources` optional parameter, the function expected the `traceStorageDir` default value to be the same directory as in which the tracePath resides. This change updates it to the `dirname(tracePath)/trace-resources` if it exists. Such a directory hirerachy is the default that is created when running the tracer in Playwright.