refactor: Restructure project layout and clean up dependencies (#30)

This commit introduces a significant reorganization of the project structure to improve maintainability and clarity.

Key changes include:
- Adjusted the directory layout for a more logical module organization.
- Removed unused crate dependencies, reducing the overall project size and potentially speeding up build times.
- Updated import paths and configuration files to reflect the structural changes.

crates/s3select-api/src/lib.rs

@@ -0,0 +1,92 @@
+// Copyright 2024 RustFS Team
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use std::fmt::Display;
+
+use datafusion::{common::DataFusionError, sql::sqlparser::parser::ParserError};
+use snafu::{Backtrace, Location, Snafu};
+
+pub mod object_store;
+pub mod query;
+pub mod server;
+
+pub type QueryResult<T> = Result<T, QueryError>;
+
+#[derive(Debug, Snafu)]
+#[snafu(visibility(pub))]
+pub enum QueryError {
+    #[snafu(display("DataFusion error: {}", source))]
+    Datafusion {
+        source: Box<DataFusionError>,
+        location: Location,
+        backtrace: Backtrace,
+    },
+
+    #[snafu(display("This feature is not implemented: {}", err))]
+    NotImplemented { err: String },
+
+    #[snafu(display("Multi-statement not allow, found num:{}, sql:{}", num, sql))]
+    MultiStatement { num: usize, sql: String },
+
+    #[snafu(display("Failed to build QueryDispatcher. err: {}", err))]
+    BuildQueryDispatcher { err: String },
+
+    #[snafu(display("The query has been canceled"))]
+    Cancel,
+
+    #[snafu(display("{}", source))]
+    Parser { source: ParserError },
+
+    #[snafu(display("Udf not exists, name:{}.", name))]
+    FunctionNotExists { name: String },
+
+    #[snafu(display("Udf already exists, name:{}.", name))]
+    FunctionExists { name: String },
+
+    #[snafu(display("Store Error, e:{}.", e))]
+    StoreError { e: String },
+}
+
+impl From<DataFusionError> for QueryError {
+    fn from(value: DataFusionError) -> Self {
+        match value {
+            DataFusionError::External(e) if e.downcast_ref::<QueryError>().is_some() => *e.downcast::<QueryError>().unwrap(),
+
+            v => Self::Datafusion {
+                source: Box::new(v),
+                location: Default::default(),
+                backtrace: Backtrace::capture(),
+            },
+        }
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct ResolvedTable {
+    // path
+    table: String,
+}
+
+impl ResolvedTable {
+    pub fn table(&self) -> &str {
+        &self.table
+    }
+}
+
+impl Display for ResolvedTable {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let Self { table } = self;
+        write!(f, "{table}")
+    }
+}