feat: pause and resume jobs from the Python SDK (#4112)

Cancellation is the only job control the SDK exposes, and it is
terminal, so a long-running server-side job cannot be parked and picked
up again. This adds `pause_job` and `resume_job` to the Rust core
connection and the Python bindings (sync and async), posting to the
server's `/v1/jobs/pause` and `/v1/jobs/resume` endpoints.

A pause parks the job until it is resumed: its workers drain and stop.
The outcome strings mirror the server's answers — a job finalizing its
results reports `"committing"` and cannot be parked, and a resume before
the drain is confirmed reports `"still_pausing"`; both are retried
rather than failed. Resuming re-queues the job and its workers pick
their work back up from checkpoints. Local connections report the
operations as unsupported, like the rest of the jobs API.

python/python/lancedb/_lancedb.pyi

@@ -188,6 +188,8 @@ class Connection(object):
     ) -> List[str]: ...
     async def list_jobs(self) -> List[JobInfo]: ...
     async def cancel_job(self, job_id: str) -> bool: ...
+    async def pause_job(self, job_id: str) -> str: ...
+    async def resume_job(self, job_id: str) -> str: ...
     async def execute_query_async(
         self,
         query: str,

python/python/lancedb/db.py

@@ -1046,6 +1046,26 @@ class DBConnection(EnforceOverrides):
             "cancel_job is not supported for this connection type"
         )
 
+    def pause_job(self, job_id: str) -> str:
+        """Pause a server-side job by id.
+
+        The job's workers drain and it stays parked until resumed. Returns
+        "pausing", "already_paused", or "committing" -- a job finalizing its
+        results cannot be parked; retry shortly.
+        """
+        raise NotImplementedError("pause_job is not supported for this connection type")
+
+    def resume_job(self, job_id: str) -> str:
+        """Resume a paused server-side job by id.
+
+        Its workers pick their work back up from checkpoints. Returns
+        "resumed", "still_pausing" -- the pause's worker drain is not
+        confirmed yet; retry shortly -- or "not_paused".
+        """
+        raise NotImplementedError(
+            "resume_job is not supported for this connection type"
+        )
+
     def execute_query(
         self,
         query: str,
@@ -1878,6 +1898,22 @@ class LanceDBConnection(DBConnection):
         """
         return LOOP.run(self._conn.cancel_job(job_id))
 
+    @override
+    def pause_job(self, job_id: str) -> str:
+        """Pause a server-side job by id.
+
+        Returns "pausing", "already_paused", or "committing".
+        """
+        return LOOP.run(self._conn.pause_job(job_id))
+
+    @override
+    def resume_job(self, job_id: str) -> str:
+        """Resume a paused server-side job by id.
+
+        Returns "resumed", "still_pausing", or "not_paused".
+        """
+        return LOOP.run(self._conn.resume_job(job_id))
+
     @override
     def namespace_client(self) -> LanceNamespace:
         """Get the equivalent namespace client for this connection.
@@ -2887,6 +2923,23 @@ class AsyncConnection(object):
         """
         return await self._inner.cancel_job(job_id)
 
+    async def pause_job(self, job_id: str) -> str:
+        """Pause a server-side job by id.
+
+        The job's workers drain and it stays parked until resumed. Returns
+        "pausing", "already_paused", or "committing" -- a job finalizing its
+        results cannot be parked; retry shortly.
+        """
+        return await self._inner.pause_job(job_id)
+
+    async def resume_job(self, job_id: str) -> str:
+        """Resume a paused server-side job by id.
+
+        Its workers pick their work back up from checkpoints. Returns
+        "resumed", "still_pausing" -- retry shortly -- or "not_paused".
+        """
+        return await self._inner.resume_job(job_id)
+
     async def execute_query(
         self,
         query: str,

python/python/lancedb/remote/db.py

@@ -957,6 +957,22 @@ class RemoteDBConnection(DBConnection):
         """
         return LOOP.run(self._conn.cancel_job(job_id))
 
+    @override
+    def pause_job(self, job_id: str) -> str:
+        """Pause a server-side job by id.
+
+        Returns "pausing", "already_paused", or "committing".
+        """
+        return LOOP.run(self._conn.pause_job(job_id))
+
+    @override
+    def resume_job(self, job_id: str) -> str:
+        """Resume a paused server-side job by id.
+
+        Returns "resumed", "still_pausing", or "not_paused".
+        """
+        return LOOP.run(self._conn.resume_job(job_id))
+
     @override
     def execute_query_async(
         self,

python/python/tests/test_remote_db.py

@@ -2628,6 +2628,26 @@ def test_remote_connection_jobs_surface():
             request.send_header("Content-Type", "application/json")
             request.end_headers()
             request.wfile.write(b'{"job_id": "job-1"}')
+        elif request.path == "/v1/jobs/pause":
+            if payload["job_id"] != "job-1":
+                request.send_response(404)
+                request.end_headers()
+                return
+            request.send_response(200)
+            request.send_header("Content-Type", "application/json")
+            request.end_headers()
+            request.wfile.write(b'{"job_id": "job-1", "paused": true}')
+        elif request.path == "/v1/jobs/resume":
+            if payload["job_id"] != "job-1":
+                request.send_response(404)
+                request.end_headers()
+                return
+            request.send_response(200)
+            request.send_header("Content-Type", "application/json")
+            request.end_headers()
+            request.wfile.write(
+                b'{"job_id": "job-1", "resumed": false, "still_pausing": true}'
+            )
         elif request.path == "/v1/jobs/query_events":
             query_events_payloads.append(payload)
             request.send_response(200)
@@ -2648,6 +2668,9 @@ def test_remote_connection_jobs_surface():
         assert db.cancel_job("job-1") is True
         assert db.cancel_job("missing") is False
 
+        assert db.pause_job("job-1") == "pausing"
+        assert db.resume_job("job-1") == "still_pausing"
+
         # Opening a job hands back a populated handle; a missing one fails.
         with pytest.raises(JobNotFoundError, match="missing"):
             db.open_job("missing")

python/src/connection.rs

@@ -982,6 +982,30 @@ impl Connection {
             inner.cancel_job(&job_id).await.infer_error()
         })
     }
+
+    pub fn pause_job(self_: PyRef<'_, Self>, job_id: String) -> PyResult<Bound<'_, PyAny>> {
+        let inner = self_.get_inner()?.clone();
+        future_into_py(self_.py(), async move {
+            let status = inner.pause_job(&job_id).await.infer_error()?;
+            Ok(match status {
+                lancedb::database::PauseJobStatus::Pausing => "pausing",
+                lancedb::database::PauseJobStatus::AlreadyPaused => "already_paused",
+                lancedb::database::PauseJobStatus::Committing => "committing",
+            })
+        })
+    }
+
+    pub fn resume_job(self_: PyRef<'_, Self>, job_id: String) -> PyResult<Bound<'_, PyAny>> {
+        let inner = self_.get_inner()?.clone();
+        future_into_py(self_.py(), async move {
+            let status = inner.resume_job(&job_id).await.infer_error()?;
+            Ok(match status {
+                lancedb::database::ResumeJobStatus::Resumed => "resumed",
+                lancedb::database::ResumeJobStatus::StillPausing => "still_pausing",
+                lancedb::database::ResumeJobStatus::NotPaused => "not_paused",
+            })
+        })
+    }
 }
 
 #[pyfunction]