refactor: make object_store optional

.github/workflows/build.yml

@@ -32,6 +32,8 @@ jobs:
       - uses: Swatinem/rust-cache@v2
       - name: build and lint with clippy
         run: cargo clippy --tests -- -D warnings
+      - name: lint without default features
+        run: cargo clippy --no-default--features -- -D warnings
   test:
     runs-on: ubuntu-latest
     steps:

kernel/Cargo.toml

@@ -21,8 +21,6 @@ either = "1.8"
 fix-hidden-lifetime-bug = "0.2"
 itertools = "0.11"
 lazy_static = "1.4"
-# used for providing a storage abstraction layer
-object_store = "^0.7.0"
 # need to generalize over arrow, arrow2 and diff parquet etc. (BYOP)
 regex = "1.8"
 roaring = "0.10.1"
@@ -37,14 +35,15 @@ z85 = "3.0.5"
 
 # Used in default client
 futures = { version = "0.3", optional = true }
+object_store = { version = "^0.7.0", optional = true }
 parquet = { version = "^46.0", optional = true, features=["async", "object_store"]}
 
 # optionally used with default client (though not required)
 tokio = { version = "1", optional = true, features=["rt-multi-thread"] }
 
 [features]
 default = ["default-client"]
-default-client = ["chrono", "parquet", "futures"]
+default-client = ["chrono", "futures", "object_store", "parquet"]
 
 [dev-dependencies]
 arrow = { version = "^46.0", features = ["json", "prettyprint"] }

kernel/src/actions/mod.rs

@@ -10,6 +10,7 @@ use itertools::izip;
 
 use crate::{DeltaResult, Error};
 
+pub(crate) mod arrow;
 pub(crate) mod schemas;
 pub(crate) mod types;
 

kernel/src/client/mod.rs

@@ -13,7 +13,6 @@ use crate::{
     DeltaResult, ExpressionHandler, FileSystemClient, JsonHandler, ParquetHandler, TableClient,
 };
 
-pub mod arrow;
 pub mod executor;
 pub mod file_handler;
 pub mod filesystem;

kernel/src/error.rs

@@ -14,9 +14,11 @@ pub enum Error {
         source: Box<dyn std::error::Error + Send + Sync + 'static>,
     },
 
+    #[cfg(feature = "parquet")]
     #[error("Arrow error: {0}")]
     Parquet(#[from] parquet::errors::ParquetError),
 
+    #[cfg(feature = "object_store")]
     #[error("Error interacting with object store: {0}")]
     ObjectStore(object_store::Error),
 
@@ -48,6 +50,7 @@ pub enum Error {
     MissingMetadata,
 }
 
+#[cfg(feature = "object_store")]
 impl From<object_store::Error> for Error {
     fn from(value: object_store::Error) -> Self {
         match value {