ccciudatu commented on code in PR #11938: URL: https://github.com/apache/datafusion/pull/11938#discussion_r1717601113
########## datafusion/core/src/datasource/flight/sql.rs: ########## @@ -0,0 +1,475 @@ +// 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. + +//! Default [FlightDriver] for Flight SQL + +use std::collections::HashMap; +use std::str::FromStr; + +use arrow_flight::error::Result; +use arrow_flight::flight_service_client::FlightServiceClient; +use arrow_flight::sql::{CommandStatementQuery, ProstMessageExt}; +use arrow_flight::{FlightDescriptor, FlightInfo, HandshakeRequest, HandshakeResponse}; +use arrow_schema::ArrowError; +use async_trait::async_trait; +use base64::prelude::BASE64_STANDARD; +use base64::Engine; +use bytes::Bytes; +use futures::{stream, TryStreamExt}; +use prost::Message; +use tonic::metadata::{AsciiMetadataKey, MetadataMap}; +use tonic::transport::Channel; +use tonic::IntoRequest; + +use crate::datasource::flight::{FlightDriver, FlightMetadata}; + +/// Default Flight SQL driver. Requires a `flight.sql.query` to be passed as a table option. +/// If `flight.sql.username` (and optionally `flight.sql.password`) are passed, +/// will perform the `Handshake` using basic authentication. +/// Any additional headers can be passed as table options using the `flight.sql.header.` prefix. +/// +/// A [crate::datasource::flight::FlightTableFactory] using this driver is registered +/// with the default `SessionContext` under the name `FLIGHT_SQL`. +#[derive(Clone, Debug, Default)] +pub struct FlightSqlDriver {} + +#[async_trait] +impl FlightDriver for FlightSqlDriver { + async fn metadata( + &self, + channel: Channel, + options: &HashMap<String, String>, + ) -> Result<FlightMetadata> { + let mut client = FlightSqlClient::new(channel); + let headers = options.iter().filter_map(|(key, value)| { + key.strip_prefix("flight.sql.header.") + .map(|header_name| (header_name, value)) + }); + for header in headers { + client.set_header(header.0, header.1) + } + if let Some(username) = options.get("flight.sql.username") { + let default_password = "".to_string(); + let password = options + .get("flight.sql.password") + .unwrap_or(&default_password); + _ = client.handshake(username, password).await?; + } + let info = client + .execute(options["flight.sql.query"].clone(), None) + .await?; + let mut grpc_metadata = MetadataMap::new(); + if let Some(token) = client.token { + grpc_metadata.insert( + "authorization", + format!("Bearer {}", token).parse().unwrap(), + ); + } + FlightMetadata::try_new(info, grpc_metadata) + } +} + +///////////////////////////////////////////////////////////////////////// +// Shameless copy/paste from arrow-flight FlightSqlServiceClient +// This is only needed in order to access the bearer token received +// during handshake, as the standard client does not expose this information. +// The bearer token has to be passed to the clients that perform +// the DoGet operation, since Dremio, Ballista and possibly others +// expect the bearer token they produce with the handshake response +// to be set on all subsequent requests, including DoGet. Review Comment: https://github.com/apache/arrow-rs/issues/6253 -- 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: github-unsubscr...@datafusion.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For additional commands, e-mail: github-h...@datafusion.apache.org
