Make ObjectStore a base class instead of a type

pyo3-object_store/src/api.rs

@@ -3,7 +3,8 @@ use pyo3::prelude::*;
 
 use crate::error::*;
 use crate::{
-    PyAzureStore, PyGCSStore, PyHttpStore, PyLocalStore, PyMemoryStore, PyPrefixStore, PyS3Store,
+    PyAzureStore, PyBaseObjectStore, PyGCSStore, PyHttpStore, PyLocalStore, PyMemoryStore,
+    PyPrefixStore, PyS3Store,
 };
 
 /// Export the default Python API as a submodule named `store` within the given parent module
@@ -46,6 +47,7 @@ pub fn register_store_module(
 
     let child_module = PyModule::new(parent_module.py(), "store")?;
 
+    child_module.add_class::<PyBaseObjectStore>()?;
     child_module.add_class::<PyAzureStore>()?;
     child_module.add_class::<PyGCSStore>()?;
     child_module.add_class::<PyHttpStore>()?;

pyo3-object_store/src/aws.rs

@@ -12,9 +12,10 @@ use crate::client::PyClientOptions;
 use crate::config::PyConfigValue;
 use crate::error::{ObstoreError, PyObjectStoreError, PyObjectStoreResult};
 use crate::retry::PyRetryConfig;
+use crate::PyBaseObjectStore;
 
 /// A Python-facing wrapper around an [`AmazonS3`].
-#[pyclass(name = "S3Store", frozen)]
+#[pyclass(name = "S3Store", frozen, extends=PyBaseObjectStore)]
 pub struct PyS3Store(Arc<AmazonS3>);
 
 impl AsRef<Arc<AmazonS3>> for PyS3Store {
@@ -41,7 +42,7 @@ impl PyS3Store {
         client_options: Option<PyClientOptions>,
         retry_config: Option<PyRetryConfig>,
         kwargs: Option<PyAmazonS3Config>,
-    ) -> PyObjectStoreResult<Self> {
+    ) -> PyObjectStoreResult<(Self, PyBaseObjectStore)> {
         let mut builder = AmazonS3Builder::from_env();
         if let Some(bucket) = bucket {
             builder = builder.with_bucket_name(bucket);
@@ -55,7 +56,7 @@ impl PyS3Store {
         if let Some(retry_config) = retry_config {
             builder = builder.with_retry(retry_config.into())
         }
-        Ok(Self(Arc::new(builder.build()?)))
+        Ok((Self(Arc::new(builder.build()?)), PyBaseObjectStore {}))
     }
 
     // Create from an existing boto3.Session or botocore.session.Session object
@@ -71,7 +72,7 @@ impl PyS3Store {
         client_options: Option<PyClientOptions>,
         retry_config: Option<PyRetryConfig>,
         kwargs: Option<PyAmazonS3Config>,
-    ) -> PyObjectStoreResult<Self> {
+    ) -> PyObjectStoreResult<(Self, PyBaseObjectStore)> {
         // boto3.Session has a region_name attribute, but botocore.session.Session does not.
         let region = if let Ok(region) = session.getattr(intern!(py, "region_name")) {
             region.extract::<Option<String>>()?
@@ -118,7 +119,7 @@ impl PyS3Store {
             builder = builder.with_retry(retry_config.into())
         }
 
-        Ok(Self(Arc::new(builder.build()?)))
+        Ok((Self(Arc::new(builder.build()?)), PyBaseObjectStore {}))
     }
 
     #[classmethod]
@@ -130,7 +131,7 @@ impl PyS3Store {
         client_options: Option<PyClientOptions>,
         retry_config: Option<PyRetryConfig>,
         kwargs: Option<PyAmazonS3Config>,
-    ) -> PyObjectStoreResult<Self> {
+    ) -> PyObjectStoreResult<(Self, PyBaseObjectStore)> {
         let mut builder = AmazonS3Builder::from_env().with_url(url);
         if let Some(config_kwargs) = combine_config_kwargs(config, kwargs)? {
             builder = config_kwargs.apply_config(builder);
@@ -141,7 +142,7 @@ impl PyS3Store {
         if let Some(retry_config) = retry_config {
             builder = builder.with_retry(retry_config.into())
         }
-        Ok(Self(Arc::new(builder.build()?)))
+        Ok((Self(Arc::new(builder.build()?)), PyBaseObjectStore {}))
     }
 
     fn __repr__(&self) -> String {

pyo3-object_store/src/base.rs

@@ -0,0 +1,5 @@
+use pyo3::prelude::*;
+
+/// Base class from which all other stores subclass
+#[pyclass(name = "BaseObjectStore", frozen, subclass)]
+pub struct PyBaseObjectStore {}

pyo3-object_store/src/lib.rs

@@ -4,6 +4,7 @@
 mod api;
 mod aws;
 mod azure;
+mod base;
 mod client;
 mod config;
 pub(crate) mod error;
@@ -18,6 +19,7 @@ mod store;
 pub use api::{register_exceptions_module, register_store_module};
 pub use aws::PyS3Store;
 pub use azure::PyAzureStore;
+pub use base::PyBaseObjectStore;
 pub use client::{PyClientConfigKey, PyClientOptions};
 pub use error::{PyObjectStoreError, PyObjectStoreResult};
 pub use gcp::PyGCSStore;