chore: require minimum mysql 8 (#1717)

BREAKING CHANGE: now depending on >= mysql 8 features

Closes STOR-160

.circleci/config.yml

@@ -271,7 +271,7 @@ jobs:
           RUST_BACKTRACE: 1
           # XXX: begin_test_transaction doesn't play nice over threaded tests
           RUST_TEST_THREADS: 1
-      - image: cimg/mysql:5.7
+      - image: cimg/mysql:8.0
         auth:
           username: $DOCKER_USER
           password: $DOCKER_PASS

README.md

@@ -37,7 +37,7 @@ Mozilla Sync Storage built with [Rust](https://rust-lang.org).
 - pkg-config
 - [Rust stable](https://rustup.rs)
 - python 3.9+
-- MySQL 5.7 (or compatible)
+- MySQL 8.0 (or compatible)
   * libmysqlclient (`brew install mysql` on macOS, `apt install libmysqlclient-dev` on Ubuntu, `apt install libmariadb-dev-compat` on Debian)
 
 Depending on your OS, you may also need to install `libgrpcdev`,

docker-compose.mysql.yaml

@@ -11,7 +11,7 @@
 version: "3"
 services:
   sync-db:
-    image: docker.io/library/mysql:5.7
+    image: docker.io/library/mysql:8.0
     volumes:
       - sync_db_data:/var/lib/mysql
     restart: always
@@ -32,7 +32,7 @@ services:
       timeout: 2s
 
   tokenserver-db:
-    image: docker.io/library/mysql:5.7
+    image: docker.io/library/mysql:8.0
     volumes:
       - tokenserver_db_data:/var/lib/mysql
     restart: always

docker-compose.spanner.yaml

@@ -26,7 +26,7 @@ services:
     environment:
       SYNC_SYNCSTORAGE__SPANNER_EMULATOR_HOST: sync-db:9020
   tokenserver-db:
-    image: docker.io/library/mysql:5.7
+    image: docker.io/library/mysql:8.0
     volumes:
       - tokenserver_db_data:/var/lib/mysql
     restart: always

syncstorage-mysql/src/diesel_ext.rs

@@ -1,43 +1,11 @@
 use diesel::{
     backend::Backend,
     insertable::CanInsertInSingleQuery,
-    mysql::Mysql,
     query_builder::{AstPass, InsertStatement, QueryFragment, QueryId},
-    query_dsl::methods::LockingDsl,
     result::QueryResult,
     Expression, RunQueryDsl, Table,
 };
 
-/// Emit MySQL <= 5.7's `LOCK IN SHARE MODE`
-///
-/// MySQL 8 supports `FOR SHARE` as an alias (which diesel natively supports)
-pub trait LockInShareModeDsl {
-    type Output;
-
-    fn lock_in_share_mode(self) -> Self::Output;
-}
-
-impl<T> LockInShareModeDsl for T
-where
-    T: LockingDsl<LockInShareMode>,
-{
-    type Output = <T as LockingDsl<LockInShareMode>>::Output;
-
-    fn lock_in_share_mode(self) -> Self::Output {
-        self.with_lock(LockInShareMode)
-    }
-}
-
-#[derive(Debug, Clone, Copy, QueryId)]
-pub struct LockInShareMode;
-
-impl QueryFragment<Mysql> for LockInShareMode {
-    fn walk_ast(&self, mut out: AstPass<'_, Mysql>) -> QueryResult<()> {
-        out.push_sql(" LOCK IN SHARE MODE");
-        Ok(())
-    }
-}
-
 #[derive(Debug, Clone)]
 pub struct OnDuplicateKeyUpdate<T, U, Op, Ret, X>(Box<InsertStatement<T, U, Op, Ret>>, X);
 

syncstorage-mysql/src/models.rs

@@ -25,7 +25,6 @@ use syncstorage_settings::{Quota, DEFAULT_MAX_TOTAL_RECORDS};
 
 use super::{
     batch,
-    diesel_ext::LockInShareModeDsl,
     error::DbError,
     pool::CollectionCache,
     schema::{bso, collections, user_collections},
@@ -178,7 +177,7 @@ impl MysqlDb {
             .select(user_collections::modified)
             .filter(user_collections::user_id.eq(user_id))
             .filter(user_collections::collection_id.eq(collection_id))
-            .lock_in_share_mode()
+            .for_share()
             .first(&self.conn)
             .optional()?;
         if let Some(modified) = modified {