refactor!: implement lazy iterators for several APIs (#4459)

Implement lazy iterators for:
- secrets
- views
- jobs
- functions
- materialized views

python/src/listing.rs

@@ -0,0 +1,131 @@
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-FileCopyrightText: Copyright The LanceDB Authors
+
+use crate::error::PythonErrorExt;
+use crate::runtime::future_into_py;
+use futures::{StreamExt, future::poll_fn};
+use lancedb::listing::{Listing, ListingOptions};
+use pyo3::exceptions::PyStopAsyncIteration;
+use pyo3::{Bound, PyAny, PyRef, PyResult, Python, pyclass, pymethods};
+use std::sync::{Arc, Mutex};
+
+pub fn options(page_token: Option<String>, page_limit: Option<u32>) -> ListingOptions {
+    let mut options = ListingOptions::default();
+    options.page_token = page_token;
+    options.page_limit = page_limit;
+    options
+}
+
+#[pyclass]
+pub struct NameListing {
+    inner: Arc<Mutex<Listing<String>>>,
+    next_lock: Arc<tokio::sync::Mutex<()>>,
+}
+impl NameListing {
+    pub fn new(inner: Listing<String>) -> Self {
+        Self {
+            inner: Arc::new(Mutex::new(inner)),
+            next_lock: Arc::new(tokio::sync::Mutex::new(())),
+        }
+    }
+}
+#[pymethods]
+impl NameListing {
+    fn num_page_results(&self, py: Python<'_>) -> usize {
+        py.detach(|| self.inner.lock().unwrap().num_page_results())
+    }
+    fn page_token(&self, py: Python<'_>) -> Option<String> {
+        py.detach(|| self.inner.lock().unwrap().page_token().map(str::to_owned))
+    }
+    fn __aiter__(self_: PyRef<'_, Self>) -> PyRef<'_, Self> {
+        self_
+    }
+    fn __anext__(self_: PyRef<'_, Self>) -> PyResult<Bound<'_, PyAny>> {
+        let inner = self_.inner.clone();
+        let next_lock = self_.next_lock.clone();
+        future_into_py(self_.py(), async move {
+            let _guard = next_lock.lock().await;
+            let value = poll_fn(|cx| inner.lock().unwrap().poll_next_unpin(cx))
+                .await
+                .ok_or_else(|| PyStopAsyncIteration::new_err(""))?
+                .infer_error()?;
+            Ok(value)
+        })
+    }
+}
+
+#[pyclass]
+pub struct FunctionListing {
+    inner: Arc<Mutex<Listing<lancedb::function::FunctionVersion>>>,
+    next_lock: Arc<tokio::sync::Mutex<()>>,
+}
+impl FunctionListing {
+    pub fn new(inner: Listing<lancedb::function::FunctionVersion>) -> Self {
+        Self {
+            inner: Arc::new(Mutex::new(inner)),
+            next_lock: Arc::new(tokio::sync::Mutex::new(())),
+        }
+    }
+}
+#[pymethods]
+impl FunctionListing {
+    fn num_page_results(&self, py: Python<'_>) -> usize {
+        py.detach(|| self.inner.lock().unwrap().num_page_results())
+    }
+    fn page_token(&self, py: Python<'_>) -> Option<String> {
+        py.detach(|| self.inner.lock().unwrap().page_token().map(str::to_owned))
+    }
+    fn __aiter__(self_: PyRef<'_, Self>) -> PyRef<'_, Self> {
+        self_
+    }
+    fn __anext__(self_: PyRef<'_, Self>) -> PyResult<Bound<'_, PyAny>> {
+        let inner = self_.inner.clone();
+        let next_lock = self_.next_lock.clone();
+        future_into_py(self_.py(), async move {
+            let _guard = next_lock.lock().await;
+            let value = poll_fn(|cx| inner.lock().unwrap().poll_next_unpin(cx))
+                .await
+                .ok_or_else(|| PyStopAsyncIteration::new_err(""))?
+                .infer_error()?;
+            value.to_canonical_json().infer_error()
+        })
+    }
+}
+
+#[pyclass]
+pub struct JobListing {
+    inner: Arc<Mutex<Listing<lancedb::database::JobInfo>>>,
+    next_lock: Arc<tokio::sync::Mutex<()>>,
+}
+impl JobListing {
+    pub fn new(inner: Listing<lancedb::database::JobInfo>) -> Self {
+        Self {
+            inner: Arc::new(Mutex::new(inner)),
+            next_lock: Arc::new(tokio::sync::Mutex::new(())),
+        }
+    }
+}
+#[pymethods]
+impl JobListing {
+    fn num_page_results(&self, py: Python<'_>) -> usize {
+        py.detach(|| self.inner.lock().unwrap().num_page_results())
+    }
+    fn page_token(&self, py: Python<'_>) -> Option<String> {
+        py.detach(|| self.inner.lock().unwrap().page_token().map(str::to_owned))
+    }
+    fn __aiter__(self_: PyRef<'_, Self>) -> PyRef<'_, Self> {
+        self_
+    }
+    fn __anext__(self_: PyRef<'_, Self>) -> PyResult<Bound<'_, PyAny>> {
+        let inner = self_.inner.clone();
+        let next_lock = self_.next_lock.clone();
+        future_into_py(self_.py(), async move {
+            let _guard = next_lock.lock().await;
+            let value = poll_fn(|cx| inner.lock().unwrap().poll_next_unpin(cx))
+                .await
+                .ok_or_else(|| PyStopAsyncIteration::new_err(""))?
+                .infer_error()?;
+            Ok(crate::job::JobInfo::from(value))
+        })
+    }
+}