feat: add build function and register it

build() function to return the database build info GreptimeTeam#2909

src/common/function/Cargo.toml

@@ -6,6 +6,7 @@ license.workspace = true
 
 [dependencies]
 arc-swap = "1.0"
+build-data = "0.1.4"
 chrono-tz = "0.6"
 common-error.workspace = true
 common-macro.workspace = true

src/common/function/src/lib.rs

@@ -13,5 +13,6 @@
 // limitations under the License.
 
 pub mod scalars;
+pub mod system;
 
 pub mod helper;

src/common/function/src/scalars/function_registry.rs

@@ -24,6 +24,7 @@ use crate::scalars::function::FunctionRef;
 use crate::scalars::math::MathFunction;
 use crate::scalars::numpy::NumpyFunction;
 use crate::scalars::timestamp::TimestampFunction;
+use crate::system::build::SystemFunction;
 
 #[derive(Default)]
 pub struct FunctionRegistry {
@@ -79,7 +80,7 @@ pub static FUNCTION_REGISTRY: Lazy<Arc<FunctionRegistry>> = Lazy::new(|| {
     DateFunction::register(&function_registry);
 
     AggregateFunctions::register(&function_registry);
-
+    SystemFunction::register(&function_registry);
     Arc::new(function_registry)
 });
 

src/common/function/src/system.rs

@@ -0,0 +1,15 @@
+// Copyright 2023 Greptime 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.
+
+pub mod build;

src/common/function/src/system/build.rs

@@ -0,0 +1,109 @@
+// Copyright 2023 Greptime 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;
+use std::sync::Arc;
+
+use common_query::error::Result;
+use common_query::prelude::{Signature, Volatility};
+use datatypes::prelude::*;
+use datatypes::vectors::{StringVector, VectorRef};
+
+use crate::scalars::function::{Function, FunctionContext};
+use crate::scalars::FunctionRegistry;
+const DEFAULT_VALUE: &str = "unknown";
+
+pub(crate) struct SystemFunction;
+/// generates rates from a sequence of adjacent data points.
+#[derive(Clone, Debug, Default)]
+pub struct BuildFunction;
+
+impl SystemFunction {
+    pub fn register(registry: &FunctionRegistry) {
+        registry.register(Arc::new(BuildFunction));
+    }
+}
+
+impl fmt::Display for BuildFunction {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "BUILD")
+    }
+}
+
+impl Function for BuildFunction {
+    fn name(&self) -> &str {
+        "build"
+    }
+
+    fn return_type(&self, _input_types: &[ConcreteDataType]) -> Result<ConcreteDataType> {
+        Ok(ConcreteDataType::string_datatype())
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::uniform(
+            0,
+            vec![ConcreteDataType::string_datatype()],
+            Volatility::Immutable,
+        )
+    }
+
+    fn eval(&self, _func_ctx: FunctionContext, _columns: &[VectorRef]) -> Result<VectorRef> {
+        let build_info = format!(
+            "branch: {}\ncommit: {}\ncommit short: {}\ndirty: {}\nversion: {}",
+            build_data::get_git_branch().unwrap_or_else(|_| DEFAULT_VALUE.to_string()),
+            build_data::get_git_commit().unwrap_or_else(|_| DEFAULT_VALUE.to_string()),
+            build_data::get_git_commit_short().unwrap_or_else(|_| DEFAULT_VALUE.to_string()),
+            build_data::get_git_dirty().map_or(DEFAULT_VALUE.to_string(), |v| v.to_string()),
+            env!("CARGO_PKG_VERSION")
+        );
+
+        let v = Arc::new(StringVector::from(vec![build_info]));
+        Ok(v)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::sync::Arc;
+
+    use common_query::prelude::TypeSignature;
+
+    use super::*;
+    #[test]
+    fn test_build_function() {
+        let build = BuildFunction;
+        assert_eq!("build", build.name());
+        assert_eq!(
+            ConcreteDataType::string_datatype(),
+            build.return_type(&[]).unwrap()
+        );
+        assert!(matches!(build.signature(),
+                         Signature {
+                             type_signature: TypeSignature::Uniform(0, valid_types),
+                             volatility: Volatility::Immutable
+                         } if  valid_types == vec![ConcreteDataType::string_datatype()]
+        ));
+        let build_info = format!(
+            "branch: {}\ncommit: {}\ncommit short: {}\ndirty: {}\nversion: {}",
+            build_data::get_git_branch().unwrap_or_else(|_| DEFAULT_VALUE.to_string()),
+            build_data::get_git_commit().unwrap_or_else(|_| DEFAULT_VALUE.to_string()),
+            build_data::get_git_commit_short().unwrap_or_else(|_| DEFAULT_VALUE.to_string()),
+            build_data::get_git_dirty().map_or(DEFAULT_VALUE.to_string(), |v| v.to_string()),
+            env!("CARGO_PKG_VERSION")
+        );
+        let vector = build.eval(FunctionContext::default(), &vec![]).unwrap();
+        let expect: VectorRef = Arc::new(StringVector::from(vec![build_info]));
+        assert_eq!(expect, vector);
+    }
+}