This PR introduces a custom CDP domain 'LP' (Lightpanda) to expose browser-specific tools. The first method, 'LP.getMarkdown', allows retrieving a Markdown representation of the DOM or a specific node by its 'nodeId'. This is optimized for AI agents and LLM-based scraping tasks.
This allows us to leverage the Caller.Function.call method, which does type
mapping, caching, etc... and allows the Zig function callback to be written like
any other Zig WebAPI function.
ReadableStream.zig was the only webapi file importing v8 directly.
Extract the repeated newFunctionWithData / callback boilerplate into
js/Local (newFunctionWithData) and js/Caller (initFromHandle,
FunctionCallbackInfo.getData), and update ReadableStream and Context
to use them.
Returns 1 when writable (default high water mark), 0 when closed,
and null when errored, matching the spec behavior for streams
without a custom queuing strategy.
After BOM stripping or when receiving an empty Uint8Array, the
decoded input can be zero-length. Per spec, empty chunks should
produce no output rather than enqueuing an empty string.
When JS called controller.enqueue(42), the value was coerced to the
string "42" because Chunk only had uint8array and string variants.
Add a js_value variant that persists the raw JS value handle, and
expose enqueueValue(js.Value) as the JS-facing enqueue method so
numbers, booleans, and objects round-trip with their original types.
- Use StaticStringMap and enums for method, tool, and resource lookups.
- Implement comptime JSON minification for tool schemas.
- Refactor router and harness to use more efficient buffered polling.
- Consolidate integration tests and add synchronous unit tests.
Replace synchronous queue-draining approach with async promise-based
piping using V8's thenAndCatch callbacks. PipeState struct manages the
async read loop: reader.read() returns a Promise, onReadFulfilled
extracts {done, value}, writes chunks to the writable side, and
recurses via pumpRead() until the stream closes.
Implement synchronous piping that drains queued chunks from a
ReadableStream into a WritableStream. pipeThrough accepts any
{readable, writable} pair (TransformStream, TextDecoderStream, etc.)
and returns the readable side. pipeTo writes all chunks to a
WritableStream and resolves when complete.
Mirrors TextEncoderStream: wraps a TransformStream with a Zig-level
transform that converts Uint8Array chunks to strings. Supports the
same constructor options as TextDecoder (label, fatal, ignoreBOM).
Add the missing Streams API types needed for TextEncoderStream support:
- WritableStream with locked/getWriter, supporting both JS sink callbacks
and internal TransformStream routing
- WritableStreamDefaultWriter with write/close/releaseLock/closed/ready
- WritableStreamDefaultController with error()
- TransformStream with readable/writable accessors, JS transformer
callbacks (start/transform/flush), and Zig-level transform support
- TransformStreamDefaultController with enqueue/error/terminate
- TextEncoderStream that encodes string chunks to UTF-8 Uint8Array
via a Zig-level transform function
In the previous commits, two separte crash resolution conspired to introduce
1 tick delay in request handling.
When we're in a libcurl perform, we can't re-enter libcurl. So we added a
check before processing new requests to make sure we weren't "performing" and,
if we were, we'd queue the request (hence the 1 tick delay).
But for another issue, we set the same "performing" check when manually
triggering callbacks. This extended the situations where the above check fired
thus causing the 1-tick delay to happen under more (and even common) situation.
This commit improves this - instead of relying on the global "performing" check
when processing 1 transfer explicitly, we now have a per-transfer performing
check. This prevents the transfer from being deinitialized during a callback
but does not block requests from being started immediately.
This field was recently added and is used to generate correct frameIds in CDP
messages. They remain the same during a navigation event, so calling them
page.id might cause surprises since navigation events create new pages, but
retain the original id. Hence, frame_id is more accurate and hopefully less
surprising.
(This is a small cleanup prior to doing some iframe navigation work).
- Refactor router and test harness for non-blocking I/O using buffered polling.
- Implement reliable test failure reporting from sub-threads to the main test runner.
- Encapsulate pipe management using idiomatic std.fs.File methods.
- Fix invalid JSON generation in resource streaming due to duplicate fields.
- Improve shutdown sequence for clean test exits.
There are two main ways to dispatch events, both via the EventManager: dispatch
and dispatchWithFunction. dispatchWithFunction came about from having to
dispatch to function callbacks in addition to event listeners. Specifically,
firing the window.onload callback.
Since that original design, much has changed. Most significantly, with
https://github.com/lightpanda-io/browser/pull/1524 callbacks defined via
attributes became properly (I hope) integrated with the event dispatching.
Furthermore, the number of non-tree event targets (e.g. AbortSignal) has grown
significantly. Finally, dispatching an event is DOM-based event is pretty
complex, involving multiple phases and capturing the path.
The current design is largely correct, but non-obvious. This commit attempts to
improve the ergonomics of event dispatching.
`dispatchWithFunction` has been renamed to `dispatchDirect`. This function is
meant to be used with non-DOM event targets. It is optimized for having an event
path with a single target andh no bubbling/capture phase. In addition to being
a little more streamlined, `dispatchDirect` will internally turn a
`js.Function.Global` or `js.Function.Temp` into a local. This makes the callsite
simpler, but also provides optimization opportunity - not having to create
a new scope for the common case of having no callback/listener. This lays the
groundwork for having a `hasDirect` guard clause at the callsite to avoid
unnecessary event creation (todo in a follow up commit).
`dispatch` remains unchanged. While `dispatch` is primarily meant to handle the
DOM-based EventTarget, it will forward non-DOM EventTargets to `dispatchDirect`.
This is necessary since JS code can call `signal.dispatchEvent(....)`.
Two notes:
1 - The flow of dispatchDirect is an optimization. The spec makes no distinction
between DOM and non-DOM based EventTargets.
2 - While the window (as an EventTarget) should probably be thought of as a
DOM-based EventTarget, we use `dispatchDirect with it. This is because it
sits at the root and thus can safely go through the faster `dispatchDirect`.
Fixes a separate but similar issue to
https://github.com/lightpanda-io/browser/pull/1689
Specifically, it prevents starting a request from within a libcurl handler, thus
avoiding an illegal recursive call.
(This commit also removes the failed function call debug logging for
DOMExceptions, as these aren't particularly abnormal / log-worthy)
