wangfenjin commented on a change in pull request #1386: URL: https://github.com/apache/arrow-rs/pull/1386#discussion_r822607916
########## File path: arrow-flight/src/sql/mod.rs ########## @@ -0,0 +1,183 @@ +// Licensed to the Apache Software Foundation (ASF) under one +// or more contributor license agreements. See the NOTICE file +// distributed with this work for additional information +// regarding copyright ownership. The ASF licenses this file +// to you 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 arrow::error::{ArrowError, Result as ArrowResult}; +use prost::Message; + +mod gen { + #![allow(clippy::all)] + include!("arrow.flight.protocol.sql.rs"); +} + +pub use gen::ActionClosePreparedStatementRequest; +pub use gen::ActionCreatePreparedStatementRequest; +pub use gen::ActionCreatePreparedStatementResult; +pub use gen::CommandGetCatalogs; +pub use gen::CommandGetCrossReference; +pub use gen::CommandGetDbSchemas; +pub use gen::CommandGetExportedKeys; +pub use gen::CommandGetImportedKeys; +pub use gen::CommandGetPrimaryKeys; +pub use gen::CommandGetSqlInfo; +pub use gen::CommandGetTableTypes; +pub use gen::CommandGetTables; +pub use gen::CommandPreparedStatementQuery; +pub use gen::CommandPreparedStatementUpdate; +pub use gen::CommandStatementQuery; +pub use gen::CommandStatementUpdate; +pub use gen::DoPutUpdateResult; +pub use gen::SqlInfo; +pub use gen::SqlNullOrdering; +pub use gen::SqlOuterJoinsSupportLevel; +pub use gen::SqlSupportedCaseSensitivity; +pub use gen::SqlSupportedElementActions; +pub use gen::SqlSupportedGroupBy; +pub use gen::SqlSupportedPositionedCommands; +pub use gen::SqlSupportedResultSetConcurrency; +pub use gen::SqlSupportedResultSetType; +pub use gen::SqlSupportedSubqueries; +pub use gen::SqlSupportedTransactions; +pub use gen::SqlSupportedUnions; +pub use gen::SqlSupportsConvert; +pub use gen::SqlTransactionIsolationLevel; +pub use gen::SupportedSqlGrammar; +pub use gen::TicketStatementQuery; +pub use gen::UpdateDeleteRules; + +pub mod server; + +/// ProstMessageExt are useful utility methods for prost::Message types +pub trait ProstMessageExt { + /// Item is the return value of prost_type::Any::unpack() + type Item: prost::Message + Default; + + /// type_url for this Message + fn type_url() -> &'static str; + + /// Convert this Message to prost_types::Any + fn as_any(&self) -> prost_types::Any; +} + +macro_rules! prost_message_ext { + ($($name:ty,)*) => { + $( + impl ProstMessageExt for $name { + type Item = $name; + fn type_url() -> &'static str { + concat!("type.googleapis.com/arrow.flight.protocol.sql.", stringify!($name)) + } + + fn as_any(&self) -> prost_types::Any { + prost_types::Any { + type_url: <$name>::type_url().to_string(), + value: self.encode_to_vec(), + } + } + } + )* + }; +} + +// Implement ProstMessageExt for all structs defined in FlightSql.proto +prost_message_ext!( + ActionClosePreparedStatementRequest, + ActionCreatePreparedStatementRequest, + ActionCreatePreparedStatementResult, + CommandGetCatalogs, + CommandGetCrossReference, + CommandGetDbSchemas, + CommandGetExportedKeys, + CommandGetImportedKeys, + CommandGetPrimaryKeys, + CommandGetSqlInfo, + CommandGetTableTypes, + CommandGetTables, + CommandPreparedStatementQuery, + CommandPreparedStatementUpdate, + CommandStatementQuery, + CommandStatementUpdate, + DoPutUpdateResult, + TicketStatementQuery, +); + +/// ProstAnyExt are useful utility methods for prost_types::Any +/// The API design is inspired by [rust-protobuf](https://github.com/stepancheg/rust-protobuf/blob/master/protobuf/src/well_known_types_util/any.rs) +pub trait ProstAnyExt { + /// Check if `Any` contains a message of given type. + fn is<M: ProstMessageExt>(&self) -> bool; + + /// Extract a message from this `Any`. + /// + /// # Returns + /// + /// * `Ok(None)` when message type mismatch + /// * `Err` when parse failed + fn unpack<M: ProstMessageExt>(&self) -> ArrowResult<Option<M::Item>>; + + /// Pack any message into `prost_types::Any` value. + fn pack<M: ProstMessageExt>(message: &M) -> ArrowResult<prost_types::Any>; +} + +impl ProstAnyExt for prost_types::Any { + fn is<M: ProstMessageExt>(&self) -> bool { + M::type_url() == self.type_url + } + + fn unpack<M: ProstMessageExt>(&self) -> ArrowResult<Option<M::Item>> { + if !self.is::<M>() { + return Ok(None); + } + let m = prost::Message::decode(&*self.value).map_err(|err| { + ArrowError::ParseError(format!("Unable to decode Any value: {}", err)) + })?; + Ok(Some(m)) + } + + fn pack<M: ProstMessageExt>(message: &M) -> ArrowResult<prost_types::Any> { + Ok(message.as_any()) + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn test_type_url() { + assert_eq!( + TicketStatementQuery::type_url(), + "type.googleapis.com/arrow.flight.protocol.sql.TicketStatementQuery" + ); + assert_eq!( + CommandStatementQuery::type_url(), + "type.googleapis.com/arrow.flight.protocol.sql.CommandStatementQuery" + ); + } + + #[test] + fn test_prost_any_pack_unpack() -> ArrowResult<()> { + let query = CommandStatementQuery { + query: "select 1".to_string(), + }; + let any = prost_types::Any::pack(&query)?; + assert!(any.is::<CommandStatementQuery>()); + let unpack_query: CommandStatementQuery = + any.unpack::<CommandStatementQuery>()?.unwrap(); Review comment: Oh, I remembered why I make it an item, it's because if I follow your style, we can even impl ProstMessageExt for String, but String is not a prost::Message. Not sure if it's an issue. My intent is I don't want non prost::Message type to impl ProstMessageExt -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
