fix(sessions): route diagnose transcript tail through accessor

zaidazmi · zaidazmi · commit c6a0b57ee374 · 2026-06-17T23:57:27.000+02:00
diff --git a/src/config/sessions/session-accessor.ts b/src/config/sessions/session-accessor.ts
@@ -607,6 +607,31 @@ export async function loadTranscriptEvents(
   return events;
 }
 
+/** Reads a bounded transcript tail through the session accessor boundary. */
+export async function readTranscriptTailLines(
+  scope: SessionTranscriptReadScope & { maxLines: number },
+): Promise<{ lines: string[]; totalLines: number } | null> {
+  const transcript = await resolveTranscriptReadAccess(scope);
+  const maxLines = Math.max(1, Math.floor(scope.maxLines));
+  const lines: string[] = [];
+  let totalLines = 0;
+  try {
+    for await (const line of streamSessionTranscriptLines(transcript.sessionFile)) {
+      if (!line.trim()) {
+        continue;
+      }
+      totalLines += 1;
+      lines.push(line);
+      if (lines.length > maxLines) {
+        lines.shift();
+      }
+    }
+  } catch {
+    return null;
+  }
+  return { lines, totalLines };
+}
+
 /**
  * Appends a non-message transcript record such as session or metadata events.
  * Message records must use appendTranscriptMessage so parent links, idempotency,
diff --git a/src/gateway/server-methods/sessions.ts b/src/gateway/server-methods/sessions.ts
@@ -66,6 +66,7 @@ import { resolveAgentMainSessionKey } from "../../config/sessions/main-session.j
 import {
   applySessionPatchProjection,
   createSessionEntryWithTranscript,
+  readTranscriptTailLines,
   trimSessionTranscriptForManualCompact,
 } from "../../config/sessions/session-accessor.js";
 import type { OpenClawConfig } from "../../config/types.openclaw.js";
@@ -107,7 +108,6 @@ import {
 import { reactivateCompletedSubagentSession } from "../session-subagent-reactivation.js";
 import {
   readRecentSessionMessagesWithStatsAsync,
-  readRecentSessionTranscriptLines,
   readSessionMessageCountAsync,
   readSessionPreviewItemsFromTranscript,
 } from "../session-transcript-readers.js";
@@ -1385,12 +1385,12 @@ function summarizeDiagnose(params: {
   };
 }
 
-function buildDiagnoseResult(params: {
+async function buildDiagnoseResult(params: {
   cfg: OpenClawConfig;
   context: GatewayRequestContext;
   p: DiagnoseParams;
   target: DiagnoseTarget;
-}): SessionsDiagnoseResult {
+}): Promise<SessionsDiagnoseResult> {
   const { cfg, context, p, target } = params;
   const now = Date.now();
   const defaultAgentId = resolveDefaultAgentId(cfg);
@@ -1451,7 +1451,7 @@ function buildDiagnoseResult(params: {
   };
   const lane = getCommandLaneSnapshot(resolveSessionLane(target.key));
   const tail = target.entry.sessionId
-    ? readRecentSessionTranscriptLines({
+    ? await readTranscriptTailLines({
         sessionId: target.entry.sessionId,
         storePath: target.storePath,
         sessionFile: target.entry.sessionFile,
@@ -1863,7 +1863,7 @@ export const sessionsHandlers: GatewayRequestHandlers = {
         );
         return;
       }
-      respond(true, buildDiagnoseResult({ cfg, context, p, target }), undefined);
+      respond(true, await buildDiagnoseResult({ cfg, context, p, target }), undefined);
     } catch (error) {
       respond(false, undefined, errorShape(ErrorCodes.INVALID_REQUEST, formatErrorMessage(error)));
     }
