Generate more typescript types and return conversation id with ConversationSummary (#3219)

This PR does multiple things that are necessary for conversation resume
to work from the extension. I wanted to make sure everything worked so
these changes wound up in one PR:
1. Generate more ts types
2. Resume rollout history files rather than create a new one every time
it is resumed so you don't see a duplicate conversation in history for
every resume. Chatted with @aibrahim-oai to verify this
3. Return conversation_id in conversation summaries
4. [Cleanup] Use serde and strong types for a lot of the rollout file
parsing

codex-rs/core/src/rollout/mod.rs

@@ -7,6 +7,8 @@ pub(crate) mod policy;
 pub mod recorder;
 
 pub use recorder::RolloutRecorder;
+pub use recorder::RolloutRecorderParams;
+pub use recorder::SessionMeta;
 pub use recorder::SessionStateSnapshot;
 
 #[cfg(test)]

codex-rs/core/src/rollout/recorder.rs

@@ -4,6 +4,7 @@ use std::fs::File;
 use std::fs::{self};
 use std::io::Error as IoError;
 use std::path::Path;
+use std::path::PathBuf;
 
 use codex_protocol::mcp_protocol::ConversationId;
 use serde::Deserialize;
@@ -26,6 +27,7 @@ use super::list::get_conversations;
 use super::policy::is_persisted_response_item;
 use crate::config::Config;
 use crate::conversation_manager::InitialHistory;
+use crate::conversation_manager::ResumedHistory;
 use crate::git_info::GitInfo;
 use crate::git_info::collect_git_info;
 use codex_protocol::models::ResponseItem;
@@ -72,12 +74,36 @@ pub struct RolloutRecorder {
     tx: Sender<RolloutCmd>,
 }
 
+#[derive(Clone)]
+pub enum RolloutRecorderParams {
+    Create {
+        conversation_id: ConversationId,
+        instructions: Option<String>,
+    },
+    Resume {
+        path: PathBuf,
+    },
+}
+
 enum RolloutCmd {
     AddItems(Vec<ResponseItem>),
     UpdateState(SessionStateSnapshot),
     Shutdown { ack: oneshot::Sender<()> },
 }
 
+impl RolloutRecorderParams {
+    pub fn new(conversation_id: ConversationId, instructions: Option<String>) -> Self {
+        Self::Create {
+            conversation_id,
+            instructions,
+        }
+    }
+
+    pub fn resume(path: PathBuf) -> Self {
+        Self::Resume { path }
+    }
+}
+
 impl RolloutRecorder {
     #[allow(dead_code)]
     /// List conversations (rollout files) under the provided Codex home directory.
@@ -92,24 +118,43 @@ impl RolloutRecorder {
     /// Attempt to create a new [`RolloutRecorder`]. If the sessions directory
     /// cannot be created or the rollout file cannot be opened we return the
     /// error so the caller can decide whether to disable persistence.
-    pub async fn new(
-        config: &Config,
-        conversation_id: ConversationId,
-        instructions: Option<String>,
-    ) -> std::io::Result<Self> {
-        let LogFileInfo {
-            file,
-            conversation_id: session_id,
-            timestamp,
-        } = create_log_file(config, conversation_id)?;
+    pub async fn new(config: &Config, params: RolloutRecorderParams) -> std::io::Result<Self> {
+        let (file, meta) = match params {
+            RolloutRecorderParams::Create {
+                conversation_id,
+                instructions,
+            } => {
+                let LogFileInfo {
+                    file,
+                    conversation_id: session_id,
+                    timestamp,
+                } = create_log_file(config, conversation_id)?;
 
-        let timestamp_format: &[FormatItem] = format_description!(
-            "[year]-[month]-[day]T[hour]:[minute]:[second].[subsecond digits:3]Z"
-        );
-        let timestamp = timestamp
-            .to_offset(time::UtcOffset::UTC)
-            .format(timestamp_format)
-            .map_err(|e| IoError::other(format!("failed to format timestamp: {e}")))?;
+                let timestamp_format: &[FormatItem] = format_description!(
+                    "[year]-[month]-[day]T[hour]:[minute]:[second].[subsecond digits:3]Z"
+                );
+                let timestamp = timestamp
+                    .to_offset(time::UtcOffset::UTC)
+                    .format(timestamp_format)
+                    .map_err(|e| IoError::other(format!("failed to format timestamp: {e}")))?;
+
+                (
+                    tokio::fs::File::from_std(file),
+                    Some(SessionMeta {
+                        timestamp,
+                        id: session_id,
+                        instructions,
+                    }),
+                )
+            }
+            RolloutRecorderParams::Resume { path } => (
+                tokio::fs::OpenOptions::new()
+                    .append(true)
+                    .open(path)
+                    .await?,
+                None,
+            ),
+        };
 
         // Clone the cwd for the spawned task to collect git info asynchronously
         let cwd = config.cwd.clone();
@@ -122,16 +167,7 @@ impl RolloutRecorder {
         // Spawn a Tokio task that owns the file handle and performs async
         // writes. Using `tokio::fs::File` keeps everything on the async I/O
         // driver instead of blocking the runtime.
-        tokio::task::spawn(rollout_writer(
-            tokio::fs::File::from_std(file),
-            rx,
-            Some(SessionMeta {
-                timestamp,
-                id: session_id,
-                instructions,
-            }),
-            cwd,
-        ));
+        tokio::task::spawn(rollout_writer(file, rx, meta, cwd));
 
         Ok(Self { tx })
     }
@@ -164,13 +200,28 @@ impl RolloutRecorder {
 
     pub async fn get_rollout_history(path: &Path) -> std::io::Result<InitialHistory> {
         info!("Resuming rollout from {path:?}");
+        tracing::error!("Resuming rollout from {path:?}");
         let text = tokio::fs::read_to_string(path).await?;
         let mut lines = text.lines();
-        let _ = lines
+        let first_line = lines
             .next()
             .ok_or_else(|| IoError::other("empty session file"))?;
-        let mut items = Vec::new();
+        let conversation_id = match serde_json::from_str::<SessionMeta>(first_line) {
+            Ok(rollout_session_meta) => {
+                tracing::error!(
+                    "Parsed conversation ID from rollout file: {:?}",
+                    rollout_session_meta.id
+                );
+                Some(rollout_session_meta.id)
+            }
+            Err(e) => {
+                return Err(IoError::other(format!(
+                    "failed to parse first line of rollout file as SessionMeta: {e}"
+                )));
+            }
+        };
 
+        let mut items = Vec::new();
         for line in lines {
             if line.trim().is_empty() {
                 continue;
@@ -198,12 +249,24 @@ impl RolloutRecorder {
             }
         }
 
-        info!("Resumed rollout successfully from {path:?}");
+        tracing::error!(
+            "Resumed rollout with {} items, conversation ID: {:?}",
+            items.len(),
+            conversation_id
+        );
+        let conversation_id = conversation_id
+            .ok_or_else(|| IoError::other("failed to parse conversation ID from rollout file"))?;
+
         if items.is_empty() {
-            Ok(InitialHistory::New)
-        } else {
-            Ok(InitialHistory::Resumed(items))
+            return Ok(InitialHistory::New);
         }
+
+        info!("Resumed rollout successfully from {path:?}");
+        Ok(InitialHistory::Resumed(ResumedHistory {
+            conversation_id,
+            history: items,
+            rollout_path: path.to_path_buf(),
+        }))
     }
 
     pub async fn shutdown(&self) -> std::io::Result<()> {
@@ -331,7 +394,7 @@ impl JsonlWriter {
     async fn write_line(&mut self, item: &impl serde::Serialize) -> std::io::Result<()> {
         let mut json = serde_json::to_string(item)?;
         json.push('\n');
-        let _ = self.file.write_all(json.as_bytes()).await;
+        self.file.write_all(json.as_bytes()).await?;
         self.file.flush().await?;
         Ok(())
     }