Murphy-OrangeMud commented on code in PR #2735: URL: https://github.com/apache/incubator-opendal/pull/2735#discussion_r1306839321
########## core/src/services/zookeeper/backend.rs: ########## @@ -0,0 +1,305 @@ +// 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 std::collections::HashMap; +use zookeeper_client as zk; + +use crate::raw::adapters::kv; +use crate::Scheme; +use async_trait::async_trait; +use tokio::sync::OnceCell; + +use crate::Builder; +use crate::Error; +use crate::ErrorKind; +use crate::*; + +use std::fmt::Debug; +use std::fmt::Formatter; +use std::io; + +use futures::future::{BoxFuture, FutureExt}; +use substring::Substring; + +use log::warn; + +const DEFAULT_ZOOKEEPER_ENDPOINT: &str = "127.0.0.1:2181"; +/// The scheme for zookeeper authentication +/// currently we do not support sasl authentication +const ZOOKEEPER_AUTH_SCHEME: &str = "digest"; + +/// Zookeeper backend builder +#[derive(Clone, Default)] +pub struct ZookeeperBuilder { + /// network address of the Zookeeper service + /// Default: 127.0.0.1:2181 + endpoint: Option<String>, + /// the user to connect to zookeeper service, default None + user: Option<String>, + /// the path to the password file of the user to connect to zookeeper service, default None + digest_path: Option<String>, +} + +impl ZookeeperBuilder { + /// Set the network addresses of zookeeper service + pub fn endpoint(&mut self, endpoint: &str) -> &mut Self { + if !endpoint.is_empty() { + self.endpoint = Some(endpoint.to_string()); + } + self + } + + /// Set the username of zookeeper service + pub fn user(&mut self, user: &str) -> &mut Self { + if !user.is_empty() { + self.user = Some(user.to_string()); + } + self + } + + /// Specify the auth digest path of zookeeper service + pub fn digest_path(&mut self, digest_path: &str) -> &mut Self { + if !digest_path.is_empty() { + self.digest_path = Some(digest_path.to_string()); + } + self + } +} + +impl Debug for ZookeeperBuilder { + fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result { + let mut ds = f.debug_struct("Builder"); + if let Some(endpoint) = self.endpoint.clone() { + ds.field("endpoint", &endpoint); + } + if let Some(user) = self.user.clone() { + ds.field("user", &user); + } + if let Some(digest_path) = self.digest_path.clone() { + ds.field("digest_path", &digest_path); + } + ds.finish() + } +} + +impl Builder for ZookeeperBuilder { + const SCHEME: Scheme = Scheme::Zookeeper; + type Accessor = ZookeeperBackend; + + fn from_map(map: HashMap<String, String>) -> Self { + let mut builder = ZookeeperBuilder::default(); + + map.get("endpoint").map(|v| builder.endpoint(v)); + map.get("user").map(|v| builder.user(v)); + map.get("digest_path").map(|v| builder.digest_path(v)); + + builder + } + + fn build(&mut self) -> Result<Self::Accessor> { + let endpoint = match self.endpoint.clone() { + None => DEFAULT_ZOOKEEPER_ENDPOINT.to_string(), + Some(endpoint) => endpoint, + }; + let (auth, acl) = match (self.user.clone(), self.digest_path.clone()) { + (Some(user), Some(digest_path)) => { + let password = std::fs::read(digest_path).map_err(parse_file_error)?; + let auth = [format!("{user}:").as_bytes().to_vec(), password].concat(); + (auth, zk::Acl::creator_all()) + } + _ => { + // TODO: change to warn + warn!("username and password isn't set, default use `anyone` acl"); + (Vec::<u8>::new(), zk::Acl::anyone_all()) + } + }; + + Ok(ZookeeperBackend::new(ZkAdapter { + endpoint, + auth, + acl, + client: OnceCell::new(), + })) + } +} + +/// Backend for Zookeeper service +pub type ZookeeperBackend = kv::Backend<ZkAdapter>; + +#[derive(Clone)] +pub struct ZkAdapter { + endpoint: String, + auth: Vec<u8>, + client: OnceCell<zk::Client>, + acl: &'static [zk::Acl], +} + +impl Debug for ZkAdapter { + fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result { + let mut ds = f.debug_struct("Adapter"); + ds.field("endpoint", &self.endpoint); + ds.field("acl", &self.acl); + ds.finish() + } +} + +impl ZkAdapter { + async fn get_connection(&self) -> Result<zk::Client> { + if let Some(client) = self.client.get() { + return Ok(client.clone()); + } + match zk::Client::connect(&self.endpoint.clone()).await { + Ok(client) => { + if !self.auth.is_empty() { + client + .auth(ZOOKEEPER_AUTH_SCHEME.to_string(), self.auth.clone()) + .await + .map_err(parse_zookeeper_error)?; + } + self.client.set(client.clone()).ok(); + Ok(client) + } + Err(e) => Err(Error::new(ErrorKind::Unexpected, "error from zookeeper").set_source(e)), + } + } + + fn create_nested_node<'a>( + &'a self, + path: &'a str, + value: &'a [u8], + ) -> BoxFuture<'a, Result<()>> { + eprintln!("{path}"); + let mut path = path.to_string(); + async move { + return match self + .get_connection() + .await? + .create( + &path, + value, + &zk::CreateOptions::new(zk::CreateMode::Persistent, self.acl), + ) + .await + { + Ok(_) => Ok(()), + Err(e) => match e { + zk::Error::NoNode => { + let idx = path.rfind('/').unwrap(); + let tmpath = path.clone(); + path = path.to_string().substring(0, idx).to_string(); + if path.as_bytes()[0] != b'/' { + path = "/".to_string() + path.strip_suffix('/').unwrap_or(&path); + } + match self.create_nested_node(&path, value).await { Review Comment: Yes, `create_nested_node()` is a recursive function that creates parent node recursively till a node exists. So when we find that the parent node doesn't exit (the NoNode error in zookeeper-client indicates this) we call this function to create the parent nodes till all the parent nodes on the path in the tree has created. Also it's because the fact that the function is both recursive and async that we use `BoxFuture`. -- 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]
