Enum TabBackend 

pub enum TabBackend {
    Cdp(Arc<CdpClient>),
    Bidi(Arc<BidiClient>),
}

Engine-agnostic tab operations. Two variants because CDP and BiDi have different protocols and clients; the methods abstract over the difference.

Variants

Cdp(Arc<CdpClient>)

Bidi(Arc<BidiClient>)

Implementations

impl TabBackend

pub async fn shutdown(&self)

Release the engine session before the client goes away. Firefox does not end a BiDi session when its WebSocket closes, so a backend that is dropped without session.end leaves the browser refusing every later session.new (“Maximum number of active sessions”). CDP has nothing to release. Best-effort and idempotent.

pub async fn create_tab(&self, url: &str) -> Result<String>

Create a fresh top-level tab. Returns the engine-specific id (CDP targetId, BiDi context) the registry stores verbatim. url defaults to about:blank.

pub async fn close_tab(&self, target_id: &str) -> Result<()>

Close a tab by id. Best-effort — both CDP and BiDi handle a missing id gracefully, and the caller’s intent (“this tab is gone”) is satisfied either way.

pub async fn navigate(&self, target_id: &str, url: &str) -> Result<()>

Navigate an existing tab to url. CDP requires attaching a transient session; BiDi takes the context id directly.

pub async fn show_tab(&self, target_id: &str) -> Result<()>

Make a tab visible and focused inside the browser window. This is intentionally explicit: normal automation creates/navigates tabs in the background so agents don’t steal the user’s foreground app unless they need interactive debugging or login.

pub async fn target_for_show(&self) -> Result<String>

Return a tab suitable for show: prefer an existing live tab, create about:blank if the browser currently has none.

pub async fn ensure_fresh( &self, target_id: &str, max_age: Duration, ) -> Result<()>

Reload an old HTTP(S) tab before reading auth-sensitive page state.

The age is measured from the document’s performance.timeOrigin. Non-web pages such as about:blank are left untouched.

pub async fn live_target_ids(&self) -> Result<HashSet<String>>

Snapshot of every live top-level tab id in the browser. Used by the registry’s sweep-on-read to drop rows whose target no longer exists.

pub async fn live_targets(&self) -> Result<Vec<LiveTarget>>

Snapshot of every live top-level tab with id + URL + title. Used by tab list --all to merge the named-tab registry with the browser’s view of the world. CDP filters to type == "page"; BiDi returns every top-level browsing context.

pub async fn resolve_or_create_for_origin(&self, url: &str) -> Result<String>

Resolve a target whose document origin matches url’s origin, reusing a live tab already on that origin if one exists and creating one rooted at the origin otherwise. Returns the engine-specific id.

This is the routing primitive for browser_fetch: running the in-page fetch from a same-origin document is what lets cookies and credentials propagate and lets the response bypass CORS. Routing a fetch through an about:blank scratch tab (this backend’s default active tab) gives it an opaque origin, which silently breaks authenticated and CORS-sensitive requests — see cli::fetch’s origin-bound path for the same contract.

pub async fn evaluate( &self, target_id: &str, expression: &str, await_promise: bool, timeout: Duration, ) -> Result<Value>

Evaluate expression in target_id’s main world, returning the raw result value (after returnByValue). Bounded by timeout; expiry returns typed SessionError::TabHung.

CDP path attaches a transient session, calls Runtime.evaluate, detaches. BiDi path calls script.evaluate against the context. On BiDi, await_promise is ignored — BiDi always awaits per script.evaluate semantics.

pub async fn screenshot( &self, target_id: &str, opts: &ScreenshotOptions, ) -> Result<String>

Capture a screenshot of target_id and return base64-encoded bytes.

CDP path attaches a transient session, calls Page.captureScreenshot, detaches. BiDi path calls browsingContext.captureScreenshot — the BiDi protocol always captures the viewport (no full_page equivalent) and has no downscale, so full_page and max_width are honoured only on CDP.

When opts.clip is Some({x, y, width, height}) (document coordinates, as produced by crate::dom::scripts::GET_CLIP_RECT_JS) the capture is restricted to that rectangle, which takes precedence over full_page. opts.max_width downscales through clip.scale, which needs no emulation override and no restore step.

pub async fn accessibility_tree( &self, target_id: &str, depth: Option<u32>, timeout: Duration, ) -> Result<Value>

Full accessibility tree (Accessibility.getFullAXTree). depth bounds the tree the browser serialises; None means everything.

pub async fn document_token( &self, target_id: &str, timeout: Duration, ) -> Result<u64>

Identity of the current document (see crate::session::input::document_token).

pub async fn click_node( &self, target_id: &str, backend_node_id: u64, timeout: Duration, ) -> Result<Point>

Click the element with backend_node_id. Returns the viewport point that was clicked.

pub async fn hover_node( &self, target_id: &str, backend_node_id: u64, timeout: Duration, ) -> Result<Point>

Hover the element with backend_node_id.

pub async fn type_into_node( &self, target_id: &str, backend_node_id: u64, text: &str, press_sequentially: bool, submit: bool, timeout: Duration, ) -> Result<()>

Replace the element’s content with text (see crate::session::input::type_text).

pub async fn drag_nodes( &self, target_id: &str, from: u64, to: u64, timeout: Duration, ) -> Result<()>

Pointer drag from one element to another.

pub async fn node_clip_rect( &self, target_id: &str, backend_node_id: u64, timeout: Duration, ) -> Result<Value>

Border box of the element in document coordinates, for clipped screenshots.

Trait Implementations

impl Clone for TabBackend

fn clone(&self) -> TabBackend

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.