From a3f814ab1fbb4f466886589639640b28a257e9bd Mon Sep 17 00:00:00 2001 From: ekexium Date: Fri, 12 Mar 2021 15:58:47 +0800 Subject: [PATCH] feat: fix batch_get_for_update Signed-off-by: ekexium --- src/kv/key.rs | 4 ++ src/kv/mod.rs | 2 +- src/request/mod.rs | 4 +- src/request/plan.rs | 105 ++++++++++++++++++++++++++++++++- src/request/plan_builder.rs | 16 +++++ src/request/shard.rs | 18 ++++++ src/transaction/requests.rs | 10 ++++ src/transaction/transaction.rs | 44 +++++++------- tests/integration_tests.rs | 43 ++++++++++++-- 9 files changed, 216 insertions(+), 30 deletions(-) diff --git a/src/kv/key.rs b/src/kv/key.rs index b46510b..1bbe11e 100644 --- a/src/kv/key.rs +++ b/src/kv/key.rs @@ -128,6 +128,10 @@ impl Key { } } +pub trait HasKeys { + fn get_keys(&self) -> Vec; +} + impl From> for Key { fn from(v: Vec) -> Self { Key(v) diff --git a/src/kv/mod.rs b/src/kv/mod.rs index e394216..7831bea 100644 --- a/src/kv/mod.rs +++ b/src/kv/mod.rs @@ -8,7 +8,7 @@ mod kvpair; mod value; pub use bound_range::{BoundRange, IntoOwnedRange}; -pub use key::Key; +pub use key::{HasKeys, Key}; pub use kvpair::KvPair; pub use value::Value; diff --git a/src/request/mod.rs b/src/request/mod.rs index 31d61be..9252280 100644 --- a/src/request/mod.rs +++ b/src/request/mod.rs @@ -10,8 +10,8 @@ use tikv_client_store::{HasError, Request}; pub use self::{ plan::{ - Collect, CollectError, DefaultProcessor, Dispatch, ExtractError, Merge, MergeResponse, - MultiRegion, Plan, Process, ProcessResponse, ResolveLock, RetryRegion, + Collect, CollectAndMatchKey, CollectError, DefaultProcessor, Dispatch, ExtractError, Merge, + MergeResponse, MultiRegion, Plan, Process, ProcessResponse, ResolveLock, RetryRegion, }, plan_builder::{PlanBuilder, SingleKey}, shard::Shardable, diff --git a/src/request/plan.rs b/src/request/plan.rs index 6e2fca3..170035c 100644 --- a/src/request/plan.rs +++ b/src/request/plan.rs @@ -2,15 +2,18 @@ use crate::{ backoff::Backoff, + kv::HasKeys, pd::PdClient, request::{KvRequest, Shardable}, stats::tikv_stats, transaction::{resolve_locks, HasLocks}, - Error, Result, + util::iter::FlatMapOkIterExt, + Error, Key, KvPair, Result, Value, }; use async_trait::async_trait; use futures::{prelude::*, stream::StreamExt}; use std::{marker::PhantomData, sync::Arc}; +use tikv_client_proto::kvrpcpb; use tikv_client_store::{HasError, HasRegionError, KvClient}; /// A plan for how to execute a request. A user builds up a plan with various @@ -55,6 +58,12 @@ impl Plan for Dispatch { } } +impl HasKeys for Dispatch { + fn get_keys(&self) -> Vec { + self.request.get_keys() + } +} + pub struct MultiRegion { pub(super) inner: P, pub pd_client: Arc, @@ -123,6 +132,9 @@ impl>>, M: Me #[derive(Clone, Copy)] pub struct Collect; +#[derive(Clone, Debug)] +pub struct CollectAndMatchKey; + /// A merge strategy which returns an error if any response is an error and /// otherwise returns a Vec of the results. #[derive(Clone, Copy)] @@ -256,6 +268,12 @@ where } } +impl HasKeys for ResolveLock { + fn get_keys(&self) -> Vec { + self.inner.get_keys() + } +} + pub struct ExtractError { pub inner: P, } @@ -292,6 +310,34 @@ where } } +// Requires: len(inner.keys) == len(inner.result) +pub struct PreserveKey { + pub inner: P, +} + +impl Clone for PreserveKey

{ + fn clone(&self) -> Self { + PreserveKey { + inner: self.inner.clone(), + } + } +} + +#[async_trait] +impl

Plan for PreserveKey

+where + P: Plan + HasKeys, +{ + type Result = ResponseAndKeys; + + async fn execute(&self) -> Result { + let keys = self.inner.get_keys(); + let res = self.inner.execute().await?; + // TODO: should we check they have the same length? + Ok(ResponseAndKeys(res, keys)) + } +} + #[cfg(test)] mod test { use super::*; @@ -349,3 +395,60 @@ mod test { .for_each(|r| assert!(r.is_err())); } } + +// contains a response and the corresponding keys +// currently only used for matching keys and values in pessimistic lock requests +#[derive(Debug, Clone)] +pub struct ResponseAndKeys(Resp, Vec); + +impl HasError for ResponseAndKeys { + fn error(&mut self) -> Option { + self.0.error() + } +} + +impl HasLocks for ResponseAndKeys { + fn take_locks(&mut self) -> Vec { + self.0.take_locks() + } +} + +impl HasRegionError for ResponseAndKeys { + fn region_error(&mut self) -> Option { + self.0.region_error() + } +} + +impl Merge> for CollectAndMatchKey { + type Out = Vec; + + fn merge( + &self, + input: Vec>>, + ) -> Result { + input + .into_iter() + .flat_map_ok(|ResponseAndKeys(mut resp, keys)| { + let values = resp.take_values(); + let not_founds = resp.take_not_founds(); + let v: Vec<_> = if not_founds.is_empty() { + // Legacy TiKV does not distiguish not existing key and existing key + // that with empty value. We assume that key does not exist if value + // is empty. + let values: Vec = values.into_iter().filter(|v| v.is_empty()).collect(); + keys.into_iter().zip(values).map(From::from).collect() + } else { + assert_eq!(values.len(), not_founds.len()); + let values: Vec = values + .into_iter() + .zip(not_founds.into_iter()) + .filter_map(|(v, not_found)| if not_found { None } else { Some(v) }) + .collect(); + keys.into_iter().zip(values).map(From::from).collect() + }; + // FIXME sucks to collect and re-iterate, but the iterators have different types + v.into_iter() + }) + .collect() + } +} diff --git a/src/request/plan_builder.rs b/src/request/plan_builder.rs index c1cf39c..7ee5a87 100644 --- a/src/request/plan_builder.rs +++ b/src/request/plan_builder.rs @@ -2,6 +2,7 @@ use crate::{ backoff::Backoff, + kv::HasKeys, pd::PdClient, request::{ DefaultProcessor, Dispatch, ExtractError, KvRequest, Merge, MergeResponse, MultiRegion, @@ -14,6 +15,8 @@ use crate::{ use std::{marker::PhantomData, sync::Arc}; use tikv_client_store::HasError; +use super::plan::PreserveKey; + /// Builder type for plans (see that module for more). pub struct PlanBuilder { pd_client: Arc, @@ -161,6 +164,19 @@ impl PlanBuilder, NoTarget> { } } +impl PlanBuilder +where + P::Result: HasError, +{ + pub fn preserve_keys(self) -> PlanBuilder, NoTarget> { + PlanBuilder { + pd_client: self.pd_client.clone(), + plan: PreserveKey { inner: self.plan }, + phantom: PhantomData, + } + } +} + impl PlanBuilder where P::Result: HasError, diff --git a/src/request/shard.rs b/src/request/shard.rs index a632783..4a565f5 100644 --- a/src/request/shard.rs +++ b/src/request/shard.rs @@ -1,6 +1,7 @@ // Copyright 2021 TiKV Project Authors. Licensed under Apache-2.0. use crate::{ + kv::HasKeys, pd::PdClient, request::{Dispatch, KvRequest, Plan, ResolveLock, RetryRegion}, store::Store, @@ -9,6 +10,8 @@ use crate::{ use futures::stream::BoxStream; use std::sync::Arc; +use super::plan::PreserveKey; + pub trait Shardable { type Shard: Send; @@ -51,6 +54,21 @@ impl Shardable for ResolveLock { } } +impl Shardable for PreserveKey

{ + type Shard = P::Shard; + + fn shards( + &self, + pd_client: &Arc, + ) -> BoxStream<'static, Result<(Self::Shard, Store)>> { + self.inner.shards(pd_client) + } + + fn apply_shard(&mut self, shard: Self::Shard, store: &Store) -> Result<()> { + self.inner.apply_shard(shard, store) + } +} + impl Shardable for RetryRegion { type Shard = P::Shard; diff --git a/src/transaction/requests.rs b/src/transaction/requests.rs index 60c49f2..6b48c21 100644 --- a/src/transaction/requests.rs +++ b/src/transaction/requests.rs @@ -1,6 +1,7 @@ // Copyright 2020 TiKV Project Authors. Licensed under Apache-2.0. use crate::{ + kv::HasKeys, pd::PdClient, request::{Collect, DefaultProcessor, KvRequest, Merge, Process, Shardable, SingleKey}, store::{store_stream_for_keys, store_stream_for_range_by_start_key, Store}, @@ -359,6 +360,15 @@ impl Shardable for kvrpcpb::PessimisticLockRequest { } } +impl HasKeys for kvrpcpb::PessimisticLockRequest { + fn get_keys(&self) -> Vec { + self.mutations + .iter() + .map(|m| m.key.clone().into()) + .collect() + } +} + impl Merge for Collect { // FIXME: PessimisticLockResponse only contains values. // We need to pair keys and values returned somewhere. diff --git a/src/transaction/transaction.rs b/src/transaction/transaction.rs index 276d8e3..6946081 100644 --- a/src/transaction/transaction.rs +++ b/src/transaction/transaction.rs @@ -3,7 +3,7 @@ use crate::{ backoff::Backoff, pd::{PdClient, PdRpcClient}, - request::{Collect, CollectError, Plan, PlanBuilder, RetryOptions}, + request::{Collect, CollectAndMatchKey, CollectError, Plan, PlanBuilder, RetryOptions}, timestamp::TimestampExt, transaction::{buffer::Buffer, lowering::*}, BoundRange, Error, Key, KvPair, Result, Value, @@ -150,10 +150,12 @@ impl Transaction { if !self.is_pessimistic() { Err(Error::InvalidTransactionType) } else { - let key = key.into(); - let mut values = self.pessimistic_lock(iter::once(key.clone()), true).await?; - assert!(values.len() == 1); - Ok(values.pop().unwrap()) + let mut pairs = self.pessimistic_lock(iter::once(key.into()), true).await?; + debug_assert!(pairs.len() <= 1); + match pairs.pop() { + Some(pair) => Ok(Some(pair.1)), + None => Ok(None), + } } } @@ -242,7 +244,7 @@ impl Transaction { /// It can only be used in pessimistic mode. /// /// # Examples - /// ```rust,no_run,compile_fail + /// ```rust,no_run /// # use tikv_client::{Key, Value, Config, TransactionClient}; /// # use futures::prelude::*; /// # use std::collections::HashMap; @@ -263,19 +265,16 @@ impl Transaction { /// ``` // This is temporarily disabled because we cannot correctly match the keys and values. // See `impl KvRequest for kvrpcpb::PessimisticLockRequest` for details. - #[allow(dead_code)] - async fn batch_get_for_update( + pub async fn batch_get_for_update( &mut self, keys: impl IntoIterator>, ) -> Result> { self.check_allow_operation()?; if !self.is_pessimistic() { - Err(Error::InvalidTransactionType) - } else { - let keys: Vec = keys.into_iter().map(|it| it.into()).collect(); - self.pessimistic_lock(keys.clone(), false).await?; - self.batch_get(keys).await + return Err(Error::InvalidTransactionType); } + let keys: Vec = keys.into_iter().map(|it| it.into()).collect(); + Ok(self.pessimistic_lock(keys, true).await?.into_iter()) } /// Create a new 'scan' request. @@ -618,42 +617,43 @@ impl Transaction { &mut self, keys: impl IntoIterator, need_value: bool, - ) -> Result>> { + ) -> Result> { assert!( matches!(self.options.kind, TransactionKind::Pessimistic(_)), "`pessimistic_lock` is only valid to use with pessimistic transactions" ); let keys: Vec = keys.into_iter().collect(); + if keys.is_empty() { + return Ok(vec![]); + } + let first_key = keys[0].clone(); let primary_lock = self.buffer.get_primary_key_or(&first_key).await; - let lock_ttl = DEFAULT_LOCK_TTL; let for_update_ts = self.rpc.clone().get_timestamp().await?; self.options.push_for_update_ts(for_update_ts.clone()); let request = new_pessimistic_lock_request( keys.clone().into_iter(), primary_lock, self.timestamp.clone(), - lock_ttl, + DEFAULT_LOCK_TTL, for_update_ts, need_value, ); let plan = PlanBuilder::new(self.rpc.clone(), request) .resolve_lock(self.options.retry_options.lock_backoff.clone()) + .preserve_keys() .multi_region() .retry_region(self.options.retry_options.region_backoff.clone()) - .merge(Collect) + .merge(CollectAndMatchKey) .plan(); - let values = plan - .execute() - .await - .map(|r| r.into_iter().map(Into::into).collect()); + let pairs = plan.execute().await; for key in keys { self.buffer.lock(key).await; } - values + pairs } /// Checks if the transaction can perform arbitrary operations. diff --git a/tests/integration_tests.rs b/tests/integration_tests.rs index 8160314..5016855 100644 --- a/tests/integration_tests.rs +++ b/tests/integration_tests.rs @@ -555,8 +555,7 @@ async fn raw_write_million() -> Result<()> { #[serial] async fn pessimistic_rollback() -> Result<()> { clear_tikv().await; - let client = - TransactionClient::new_with_config(vec!["127.0.0.1:2379"], Default::default()).await?; + let client = TransactionClient::new_with_config(pd_addrs(), Default::default()).await?; let mut preload_txn = client.begin_optimistic().await?; let key1 = vec![1]; let value = key1.clone(); @@ -587,8 +586,7 @@ async fn pessimistic_rollback() -> Result<()> { #[serial] async fn lock_keys() -> Result<()> { clear_tikv().await; - let client = - TransactionClient::new_with_config(vec!["127.0.0.1:2379"], Default::default()).await?; + let client = TransactionClient::new_with_config(pd_addrs(), Default::default()).await?; let k1 = b"key1".to_vec(); let k2 = b"key2".to_vec(); @@ -617,6 +615,43 @@ async fn lock_keys() -> Result<()> { Ok(()) } + +#[tokio::test] +#[serial] +async fn get_for_update() -> Result<()> { + clear_tikv().await; + let client = TransactionClient::new_with_config(pd_addrs(), Default::default()).await?; + let key1 = "key".to_owned(); + let key2 = "another key".to_owned(); + let value1 = b"some value".to_owned(); + let value2 = b"another value".to_owned(); + let keys = vec![key1.clone(), key2.clone()]; + + let mut t1 = client.begin_pessimistic().await?; + let mut t2 = client.begin_pessimistic().await?; + + let mut t0 = client.begin_pessimistic().await?; + t0.put(key1.clone(), value1).await?; + t0.put(key2.clone(), value2).await?; + t0.commit().await?; + + assert!(t1.get(key1.clone()).await?.is_none()); + assert!(t1.get_for_update(key1.clone()).await?.unwrap() == value1); + t1.commit().await?; + + assert!(t2.batch_get(keys.clone()).await?.collect::>().len() == 0); + let res: HashMap<_, _> = t2 + .batch_get_for_update(keys.clone()) + .await? + .map(From::from) + .collect(); + t2.commit().await?; + assert!(res.get(&key1.into()).unwrap() == &value1); + assert!(res.get(&key2.into()).unwrap() == &value2); + + Ok(()) +} + // helper function async fn get_u32(client: &RawClient, key: Vec) -> Result { let x = client.get(key).await?.unwrap();