feat(bindings/python): Support exists API for python binding

Co-authored-by: Zheao Li <me@manjusaka.me>
Signed-off-by: Manjusaka <me@manjusaka.me>
Signed-off-by: Yashika soni <soniyashika164@gmail.com>

bindings/python/python/opendal/__init__.pyi

@@ -48,6 +48,7 @@ class Operator:
     def copy(self, source: str, target: str) -> None: ...
     def rename(self, source: str, target: str) -> None: ...
     def remove_all(self, path: str) -> None: ...
+    def exists(self, path: str) -> bool: ...
     def to_async_operator(self) -> AsyncOperator: ...
 
 @final
@@ -81,6 +82,7 @@ class AsyncOperator:
     async def copy(self, source: str, target: str) -> None: ...
     async def rename(self, source: str, target: str) -> None: ...
     async def remove_all(self, path: str) -> None: ...
+    async def exists(self, path: str) -> bool: ...
     def to_operator(self) -> Operator: ...
 
 @final

bindings/python/src/operator.rs

@@ -398,6 +398,13 @@ impl AsyncOperator {
         })
     }
 
+    pub fn exists<'p>(&'p self, py: Python<'p>, path: String) -> PyResult<Bound<PyAny>> {
+        let this = self.core.clone();
+        future_into_py(
+            py,
+            async move { this.exists(&path).await.map_err(format_pyerr) },
+        )
+    }
     /// Create a dir at given path.
     ///
     /// # Notes

bindings/python/tests/test_exists.py

@@ -0,0 +1,29 @@
+import os
+from random import randint
+from uuid import uuid4
+
+import pytest
+
+
+@pytest.mark.need_capability("write", "delete", "stat")
+def test_sync_exists(service_name, operator, async_operator):
+    size = randint(1, 1024)
+    filename = f"test_file_{str(uuid4())}.txt"
+    content = os.urandom(size)
+    size = len(content)
+    operator.write(filename, content)
+    assert operator.exists(filename)
+    assert not operator.exists(filename + "not_exists")
+
+
+@pytest.mark.asyncio
+@pytest.mark.need_capability("write", "delete", "stat")
+async def test_async_exists(service_name, operator, async_operator):
+    size = randint(1, 1024)
+    filename = f"test_file_{str(uuid4())}.txt"
+    content = os.urandom(size)
+    size = len(content)
+    await async_operator.write(filename, content)
+    assert await async_operator.exists(filename)
+    assert not await async_operator.exists(filename + "not_exists")
+    await async_operator.delete(filename)