docs(hf): document bucket support and update service table

core/README.md

@@ -29,7 +29,7 @@ OpenDAL supports the following storage [services](https://docs.rs/opendal/latest
 | Type                           | Services                                                                                                                                 | 
 |--------------------------------|------------------------------------------------------------------------------------------------------------------------------------------| 
 | Standard Storage Protocols     | ftp http [sftp] [webdav]                                                                                                                 |
-| Object Storage Services        | [azblob] [cos] [gcs] [obs] [oss] [s3] <br> [b2] [openstack_swift] [upyun] [vercel-blob]                                                  |
+| Object Storage Services        | [azblob] [cos] [gcs] [obs] [oss] [s3] <br> [b2] [huggingface] [openstack_swift] [upyun] [vercel-blob]                                    |
 | File Storage Services          | fs [alluxio] [azdls] [azfile] [compfs] <br> [dbfs] [gridfs] [hdfs] [hdfs-native] [ipfs] [webhdfs]                                        |
 | Consumer Cloud Storage Service | [aliyun-drive] [gdrive] [onedrive] [dropbox] [koofr] <br> [pcloud] [seafile] [yandex-disk]                                      |
 | Key-Value Storage Services     | [cacache] [cloudflare-kv] [dashmap] memory [etcd] <br> [foundationdb] [persy] [redis] [rocksdb] [sled] <br> [redb] [tikv] |

core/services/hf/src/docs.md

@@ -2,7 +2,12 @@ This service will visit the [Hugging Face API](https://huggingface.co/docs/huggi
 
 Hugging Face doesn't host official HTTP API docs. Detailed HTTP request API information can be found on the [`huggingface_hub` Source Code](https://github.com/huggingface/huggingface_hub).
 
-Both `hf://` and `huggingface://` URI schemes are supported.
+## Storage Backends
+
+This service supports two storage backends:
+
+- **Git-based repositories** (`model`, `dataset`, `space`): Files are versioned in a Git repository. Large files are stored via [Xet](https://huggingface.co/docs/hub/xet/index), Hugging Face's chunk-deduplicated storage backend; writes create new commits. Supports `revision` for branch/commit targeting.
+- **Object store buckets** (`bucket`): Files are stored in a Hugging Face Bucket (not git-backed). No revisions or commits — all reads and writes use the [Xet](https://huggingface.co/docs/hub/xet/index) protocol directly.
 
 ## Capabilities
 
@@ -16,21 +21,22 @@ This service can be used to:
 - [x] list
 - [ ] copy
 - [ ] rename
-- [ ] ~~presign~~
+- [ ] presign
 
 ## Configurations
 
-- `repo_type`: The type of the repository (model, dataset, or space).
+- `repo_type`: The type of the repository. One of `model`, `dataset`, `space`, or `bucket`.
 - `repo_id`: The id of the repository.
-- `revision`: The revision of the repository.
+- `revision`: The revision of the repository. Only applicable for git-based repo types (`model`, `dataset`, `space`).
 - `root`: Set the work directory for backend.
 - `token`: The token for accessing the repository. Required for write operations.
+- `endpoint`: The Hub base URL. Default is `https://huggingface.co`. Can also be set via the `HF_ENDPOINT` environment variable.
 
 Refer to [`HfBuilder`]'s public API docs for more information.
 
 ## Examples
 
-### Via Builder
+### Via Builder (Git-based dataset)
 
 ```rust,no_run
 use opendal_core::Operator;
@@ -39,21 +45,59 @@ use opendal_service_hf::Hf;
 
 #[tokio::main]
 async fn main() -> Result<()> {
-    // Create Hugging Face backend builder
-    let mut builder = Hf::default()
-        // set the type of Hugging Face repository
+    let builder = Hf::default()
         .repo_type("dataset")
-        // set the id of Hugging Face repository
-        .repo_id("databricks/databricks-dolly-15k")
-        // set the revision of Hugging Face repository
+        .repo_id("username/my-dataset")
         .revision("main")
-        // set the root, all operations will happen under this root
         .root("/path/to/dir")
-        // set the token for accessing the repository
         .token("access_token");
 
     let op: Operator = Operator::new(builder)?.finish();
 
     Ok(())
 }
 ```
+
+### Via Builder (Object store bucket)
+
+```rust,no_run
+use opendal_core::Operator;
+use opendal_core::Result;
+use opendal_service_hf::Hf;
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    let builder = Hf::default()
+        .repo_type("bucket")
+        .repo_id("username/my-bucket")
+        .token("access_token");
+
+    let op: Operator = Operator::new(builder)?.finish();
+
+    Ok(())
+}
+```
+
+### Via URI
+
+```rust,no_run
+use opendal_core::Operator;
+use opendal_core::Result;
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    // Git-based dataset
+    let op = Operator::from_uri((
+        "hf://datasets/username/my-dataset@main",
+        vec![("token", "access_token")],
+    ))?;
+
+    // Object store bucket
+    let op = Operator::from_uri((
+        "hf://buckets/username/my-bucket",
+        vec![("token", "access_token")],
+    ))?;
+
+    Ok(())
+}
+```