feat(backend)!: remove s3 and sftp wrapper around opendal (#200)

`s3` and `sftp` can be used with `opendal`. Users didn't complain that
using `opendal` poses any problems or inconveniences.
The current wrapper also have some unfixed bugs, so we remove them.

closes rustic-rs/rustic#1045
closes rustic-rs/rustic#1047

---------

Signed-off-by: simonsan <[email protected]>

Author: simonsan

crates/backend/Cargo.toml

@@ -31,16 +31,13 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [features]
-default = ["opendal", "s3", "sftp", "rest", "rclone"]
+default = ["opendal", "rest", "rclone"]
 cli = ["merge", "clap"]
 merge = ["dep:merge"]
 clap = ["dep:clap"]
-s3 = ["opendal"]
 opendal = ["dep:opendal", "dep:rayon", "dep:tokio", "tokio/rt-multi-thread"]
 rest = ["dep:reqwest", "dep:backoff"]
 rclone = ["rest", "dep:rand", "dep:semver"]
-# Note: sftp is not yet supported on windows, see below
-sftp = ["opendal"]
 
 [dependencies]
 # core

crates/backend/README.md

@@ -14,8 +14,8 @@
 This library is a part of the [rustic](https://rustic.cli.rs) project and
 provides a set of backends for the
 [`rustic_core`](https://crates.io/crates/rustic_core) library. It is used to
-interact with various storage backends, such as `s3`, `rclone`, `rest`, `sftp`,
-and in general `opendal`.
+interact with various storage backends, such as `rclone`, `rest`, and in general
+`opendal`.
 
 The goal of this library is to provide a unified interface for interacting with
 various backends, so that the
@@ -72,12 +72,6 @@ This crate exposes a few features for controlling dependency usage:
 - **rest** - Enables support for the `rest` backend. *This feature is enabled by
   default*.
 
-- **sftp** - Enables support for the `sftp` backend. Windows is not yet
-  supported. *This feature is enabled by default*.
-
-- **s3** - Enables support for the `s3` backend. *This feature is enabled by
-  default*.
-
 ## Usage & Examples
 
 Due to being a support crate for

crates/backend/src/choose.rs

@@ -13,12 +13,6 @@ use crate::{
     util::{location_to_type_and_path, BackendLocation},
 };
 
-#[cfg(feature = "s3")]
-use crate::opendal::s3::S3Backend;
-
-#[cfg(all(unix, feature = "sftp"))]
-use crate::opendal::sftp::SftpBackend;
-
 #[cfg(feature = "opendal")]
 use crate::opendal::OpenDALBackend;
 
@@ -156,7 +150,7 @@ pub trait BackendChoice {
 
 /// The supported backend types.
 ///
-/// Currently supported types are "local", "rclone", "rest", "opendal", "s3"
+/// Currently supported types are "local", "rclone", "rest", "opendal"
 ///
 /// # Notes
 ///
@@ -182,16 +176,6 @@ pub enum SupportedBackend {
     /// An openDAL backend (general)
     #[strum(serialize = "opendal", to_string = "openDAL Backend")]
     OpenDAL,
-
-    #[cfg(feature = "s3")]
-    /// An openDAL S3 backend
-    #[strum(serialize = "s3", to_string = "S3 Backend")]
-    S3,
-
-    #[cfg(all(unix, feature = "sftp"))]
-    /// An openDAL sftp backend
-    #[strum(serialize = "sftp", to_string = "sftp Backend")]
-    Sftp,
 }
 
 impl BackendChoice for SupportedBackend {
@@ -210,10 +194,6 @@ impl BackendChoice for SupportedBackend {
             Self::Rest => Arc::new(RestBackend::new(location, options)?),
             #[cfg(feature = "opendal")]
             Self::OpenDAL => Arc::new(OpenDALBackend::new(location, options)?),
-            #[cfg(feature = "s3")]
-            Self::S3 => Arc::new(S3Backend::new(location, options)?),
-            #[cfg(all(unix, feature = "sftp"))]
-            Self::Sftp => Arc::new(SftpBackend::new(location, options)?),
         })
     }
 }
@@ -233,8 +213,6 @@ mod tests {
     #[case("rest", SupportedBackend::Rest)]
     #[cfg(feature = "opendal")]
     #[case("opendal", SupportedBackend::OpenDAL)]
-    #[cfg(feature = "s3")]
-    #[case("s3", SupportedBackend::S3)]
     fn test_try_from_is_ok(#[case] input: &str, #[case] expected: SupportedBackend) {
         assert_eq!(SupportedBackend::try_from(input).unwrap(), expected);
     }

crates/backend/src/lib.rs

@@ -19,8 +19,6 @@ The following backends are currently supported and can be enabled with features:
 - `OpenDALBackend` - Backend for accessing a `OpenDAL` filesystem.
 - `RcloneBackend` - Backend for accessing a Rclone filesystem.
 - `RestBackend` - Backend for accessing a REST API.
-- `SftpBackend` - Backend for accessing a SFTP filesystem.
-- `S3Backend` - Backend for accessing a S3 filesystem.
 
 ## Usage & Examples
 
@@ -46,17 +44,12 @@ This crate exposes a few features for controlling dependency usage:
 
 - **opendal** - Enables support for the `opendal` backend. *This feature is
   enabled by default*.
+
 - **rclone** - Enables support for the `rclone` backend. *This feature is
   enabled by default*.
 
 - **rest** - Enables support for the `rest` backend. *This feature is enabled by
   default*.
-
-- **sftp** - Enables support for the `sftp` backend. Windows is not yet
-  supported. *This feature is enabled by default*.
-
-- **s3** - Enables support for the `s3` backend. *This feature is enabled by
-  default*.
 */
 
 pub mod choose;
@@ -82,12 +75,6 @@ pub use crate::{
     local::LocalBackend,
 };
 
-#[cfg(all(unix, feature = "sftp"))]
-pub use crate::opendal::sftp::SftpBackend;
-
-#[cfg(feature = "s3")]
-pub use crate::opendal::s3::S3Backend;
-
 #[cfg(feature = "opendal")]
 pub use crate::opendal::OpenDALBackend;
 

crates/backend/src/opendal.rs

@@ -1,10 +1,4 @@
-/// `OpenDAL` S3 backend for Rustic.
-#[cfg(feature = "s3")]
-pub mod s3;
-/// `OpenDAL` SFTP backend for Rustic.
-#[cfg(all(unix, feature = "sftp"))]
-pub mod sftp;
-
+/// `OpenDAL` backend for rustic.
 use std::{collections::HashMap, path::PathBuf, str::FromStr, sync::OnceLock};
 
 use anyhow::Result;
@@ -19,7 +13,7 @@ use tokio::runtime::Runtime;
 
 use rustic_core::{FileType, Id, ReadBackend, WriteBackend, ALL_FILE_TYPES};
 
-mod consts {
+mod constants {
     /// Default number of retries
     pub(super) const DEFAULT_RETRY: usize = 5;
 }
@@ -58,7 +52,7 @@ impl OpenDALBackend {
     pub fn new(path: impl AsRef<str>, options: HashMap<String, String>) -> Result<Self> {
         let max_retries = match options.get("retry").map(String::as_str) {
             Some("false" | "off") => 0,
-            None | Some("default") => consts::DEFAULT_RETRY,
+            None | Some("default") => constants::DEFAULT_RETRY,
             Some(value) => usize::from_str(value)?,
         };
         let connections = options