Implement function to fetch existing targets when connecting to exist…

…ing chromium instance (#187)

* feat(browser): fetch existing targets(pages)

* rustfmt

---------

Co-authored-by: Matthias Seitz <[email protected]>

src/browser.rs

@@ -13,6 +13,7 @@ use futures::SinkExt;
 
 use chromiumoxide_cdp::cdp::browser_protocol::target::{
     CreateBrowserContextParams, CreateTargetParams, DisposeBrowserContextParams, TargetId,
+    TargetInfo,
 };
 use chromiumoxide_cdp::cdp::{CdpEventMessage, IntoEventKind};
 use chromiumoxide_types::*;
@@ -177,6 +178,26 @@ impl Browser {
         Ok((browser, fut))
     }
 
+    /// Request to fetch all existing browser targets.
+    ///
+    /// By default, only targets launched after the browser connection are tracked
+    /// when connecting to a existing browser instance with the devtools websocket url
+    /// This function fetches existing targets on the browser and adds them as pages internally
+    ///
+    /// The pages are not guaranteed to be ready as soon as the function returns
+    /// You should wait a few millis if you need to use a page
+    /// Returns [TargetInfo]
+    pub async fn fetch_targets(&mut self) -> Result<Vec<TargetInfo>> {
+        let (tx, rx) = oneshot_channel();
+
+        self.sender
+            .clone()
+            .send(HandlerMessage::FetchTargets(tx))
+            .await?;
+
+        rx.await?
+    }
+
     /// Request for the browser to close completely.
     ///
     /// If the browser was spawned by [`Browser::launch`], it is recommended to wait for the

src/handler/mod.rs

@@ -213,6 +213,30 @@ impl Handler {
                         }
                     }
                 }
+                PendingRequest::GetTargets(tx) => {
+                    match to_command_response::<GetTargetsParams>(resp, method) {
+                        Ok(resp) => {
+                            let targets: Vec<TargetInfo> = resp.result.target_infos;
+                            let results = targets.clone();
+                            for target_info in targets {
+                                let target_id = target_info.target_id.clone();
+                                let event: EventTargetCreated = EventTargetCreated { target_info };
+                                self.on_target_created(event);
+                                let attach = AttachToTargetParams::new(target_id);
+                                let _ = self.conn.submit_command(
+                                    attach.identifier(),
+                                    None,
+                                    serde_json::to_value(attach).unwrap(),
+                                );
+                            }
+
+                            let _ = tx.send(Ok(results)).ok();
+                        }
+                        Err(err) => {
+                            let _ = tx.send(Err(err)).ok();
+                        }
+                    }
+                }
                 PendingRequest::Navigate(id) => {
                     self.on_navigation_response(id, resp);
                 }
@@ -266,6 +290,18 @@ impl Handler {
         Ok(())
     }
 
+    fn submit_fetch_targets(&mut self, tx: OneshotSender<Result<Vec<TargetInfo>>>, now: Instant) {
+        let msg = GetTargetsParams { filter: None };
+        let method = msg.identifier();
+        let call_id = self
+            .conn
+            .submit_command(method.clone(), None, serde_json::to_value(msg).unwrap())
+            .unwrap();
+
+        self.pending_commands
+            .insert(call_id, (PendingRequest::GetTargets(tx), method, now));
+    }
+
     /// Send the Request over to the server and store its identifier to handle
     /// the response once received.
     fn submit_navigation(&mut self, id: NavigationId, req: CdpRequest, now: Instant) {
@@ -456,6 +492,9 @@ impl Handler {
                     PendingRequest::CreateTarget(tx) => {
                         let _ = tx.send(Err(CdpError::Timeout));
                     }
+                    PendingRequest::GetTargets(tx) => {
+                        let _ = tx.send(Err(CdpError::Timeout));
+                    }
                     PendingRequest::Navigate(nav) => {
                         if let Some(nav) = self.navigations.remove(&nav) {
                             match nav {
@@ -498,6 +537,9 @@ impl Stream for Handler {
                     HandlerMessage::Command(cmd) => {
                         pin.submit_external_command(cmd, now)?;
                     }
+                    HandlerMessage::FetchTargets(tx) => {
+                        pin.submit_fetch_targets(tx, now);
+                    }
                     HandlerMessage::CloseBrowser(tx) => {
                         pin.submit_close(tx, now);
                     }
@@ -679,6 +721,8 @@ enum PendingRequest {
     /// A Request to create a new `Target` that results in the creation of a
     /// `Page` that represents a browser page.
     CreateTarget(OneshotSender<Result<Page>>),
+    /// A Request to fetch old `Target`s created before connection
+    GetTargets(OneshotSender<Result<Vec<TargetInfo>>>),
     /// A Request to navigate a specific `Target`.
     ///
     /// Navigation requests are not automatically completed once the response to
@@ -701,6 +745,7 @@ enum PendingRequest {
 #[derive(Debug)]
 pub(crate) enum HandlerMessage {
     CreatePage(CreateTargetParams, OneshotSender<Result<Page>>),
+    FetchTargets(OneshotSender<Result<Vec<TargetInfo>>>),
     InsertContext(BrowserContext),
     DisposeContext(BrowserContext),
     GetPages(OneshotSender<Vec<Page>>),