【从零开始的rust web开发之路 三】orm框架sea-orm入门使用教程

【从零开始的rust web开发之路 三】orm框架sea-orm入门使用教程

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前言

前两篇文件主要降了axum相关使用，这篇文章来讲讲orm相关框架。目前rust orm相关框架不多，比较主流的是sqlx，本文介绍的框架实在此基础上封装的一层，sql-orm同样也支持rust异步。

一、引入依赖

sea-orm = { version = "0.12", features = [ <DATABASE_DRIVER>, <ASYNC_RUNTIME>, "macros" ] }  #DATABASE_DRIVER和ASYNC_RUNTIME参数需要替换

DATABASE_DRIVER参数

• sqlx-mysql-SQLx的MySQL
• sqlx-postgres-SQLx
• PostgreSQL的 sqlx-sqlite

ASYNC_RUNTIME参数

• runtime-async-std-native-tls
• runtime-tokio-native-tls
• runtime-async-std-rustls
• runtime-tokio-rustls
  这里我们选择引入tokio异步支持的，还要引入tokio

[dependencies]
sea-orm = { version = "0.12", features = [ "sqlx-mysql", "runtime-tokio-native-tls", "macros" ] }
tokio = { version = "1.35.1", features = ["full"] }

二、创建数据库连接

简单链接

let db: DatabaseConnection = Database::connect("protocol://username:password@host/database").await?;

举例子mysql数据库连接

   let db: DatabaseConnection = Database::connect("mysql://root:[email protected]:3307/test").await.unwrap();

后续查询选相关操作每次调用DatabaseConnection ，都会从池中获取和释放连接。
连接别的数据库可以看官方文档https://www.sea-ql.org/SeaORM/docs/next/install-and-config/connection/

连接选项

若要配置连接，请使用 ConnectOptions 接口

let mut opt = ConnectOptions::new("mysql://root:[email protected]:3307/test");
opt.max_connections(100)
    .min_connections(5)
    .connect_timeout(Duration::from_secs(8))
    .acquire_timeout(Duration::from_secs(8))
    .idle_timeout(Duration::from_secs(8))
    .max_lifetime(Duration::from_secs(8))
    .sqlx_logging(true)
    .sqlx_logging_level(log::LevelFilter::Info)
    .set_schema_search_path("my_schema"); // Setting default PostgreSQL schema

let db = Database::connect(opt).await?;

可以看ConnectOptions接口文档https://docs.rs/sea-orm/0.12.12/sea_orm/struct.ConnectOptions.html

开启日志调试

开发阶段需要打印相关日志，可以开启调试模式
features当中多一个[“debug-print”]

[dependencies]
sea-orm = { version = "0.12", features = [ "sqlx-mysql", "runtime-tokio-native-tls", "macros" ,"debug-print","with-chrono"] }
tokio = { version = "1.35.1", features = ["full"] }
chrono = "0.4.33"
tracing = "0.1.40"
tracing-subscriber = { version = "0.3.18",features = [
    "env-filter",
    "time",
    "local-time", ]}

然后需要执行一段初始化tracing-subscriber代码

    // 设置全局日志级别为 info
    let env_filter = EnvFilter::try_from_default_env().unwrap_or_else(|_| EnvFilter::new("info"))
        //单独设置sea_orm
        .add_directive("sea_orm::driver=debug".parse().unwrap())
        //关闭sqlx自带的日志
        .add_directive("sqlx::query=off".parse().unwrap());

三、生成实体

安装sea-orm-cli

运行命令

cargo install sea-orm-cli

创建数据库表

CREATE TABLE `user` (
  `id` int NOT NULL AUTO_INCREMENT,
  `username` varchar(32) NOT NULL COMMENT '用户名称',
  `birthday` datetime DEFAULT NULL COMMENT '生日',
  `sex` char(1) DEFAULT NULL COMMENT '性别',
  `address` varchar(256) DEFAULT NULL COMMENT '地址',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=49 DEFAULT CHARSET=utf8mb3

使用sea-orm-cli命令生成实体文件代码

在项目文件夹下运行命令，-o 是输出文件目录。相关参数配置可看文档https://www.sea-ql.org/SeaORM/docs/next/generate-entity/sea-orm-cli/

sea-orm-cli generate entity -u mysql://root:[email protected]:3307/test -o src/entity

在main文件加入entity模块即可。
生成的文件内容
在这里插入图片描述

指定表名

#[sea_orm(table_name = "cake", schema_name = "public")]
pub struct Model { ... }

指定列名

#[sea_orm(column_name = "name")]
pub name: String

四、增删改查实现

新增数据

先了解ActiveValue和ActiveModel

use entity::user::ActiveModel as UserModel;
let user: UserModel =  UserModel{
        id: ActiveValue::NotSet,
        username: ActiveValue::Set("你好".to_owned()),
        birthday: ActiveValue::Set(Some(Local::now().naive_local())),
        sex: ActiveValue::Set(Some("1".to_owned())),
        address: ActiveValue::Set(Some("address".to_owned())),
    };

这里我们创建UserModel的ActiveModel模型，里面的值是ActiveValue类型，NotSet是不设置值。
创建ActiveModel方法还有别的，比如通过JSON字符，具体的可以看文档https://www.sea-ql.org/SeaORM/docs/next/basic-crud/insert/#convert-activemodel-back-to-model
然后执行插入方法，具体代码如下

use chrono::{ Local};
use sea_orm::{ActiveModelTrait, ActiveValue, Database, DatabaseConnection, IntoActiveModel};

pub mod entity;
use entity::user::Entity as UserDao;
use entity::user::ActiveModel as UserModel;
use entity::user::Model as Model;
#[tokio::main]
async fn main(){
    let db: DatabaseConnection = Database::connect("mysql://root:[email protected]:3307/test").await.unwrap();
    let user: UserModel =  UserModel{
        id: ActiveValue::NotSet,
        username: ActiveValue::Set("你好".to_owned()),
        birthday: ActiveValue::Set(Some(Local::now().naive_local())),
        sex: ActiveValue::Set(Some("1".to_owned())),
        address: ActiveValue::Set(Some("address".to_owned())),
    };
/*    let user: Model = Model{
        id: 1,
        username: "admin".to_string(),
        birthday: Some(Local::now().naive_local()),
        sex: Some("1".to_owned()),
        address: Some("address".to_owned()),
    };
    let active_model = user.into_active_model();*/
    let result = user.insert(&db).await.unwrap();
    println!("插入成功！：{:?}",result);
}

多个插入可以调用上述代码UserDao中的insert_many方法，传入ActiveModel数组

主键查找

use entity::user::Entity as UserDao;
 let option = UserDao::find_by_id(1).one(&db).await.unwrap();
    match option {
        None => {}
        Some(user) => println!("查询成功！：{:?}",user)
    }

条件查找

查找用户名是admin的一条用户

use crate::entity::user;
    use entity::user::Entity as UserDao;
    let result = UserDao::find().filter(user::Column::Username.eq("admin")).one(&db).await.unwrap();
    match result {
        None => {}
        Some(user) => println!("查询成功！：{:?}",user)
    }

查找地址是郑州的所有用户

    use crate::entity::user;
    use entity::user::Entity as UserDao;
    let result = UserDao::find().filter(user::Column::Address.eq("郑州")).all(&db).await.unwrap();
    println!("查询成功！：{:?}",result)

查找地址是郑州并且用户名包含admin的所有用户

    use crate::entity::user;
    use entity::user::Entity as UserDao;
    let result = UserDao::find().filter(
        Condition::all().add(user::Column::Address.eq("郑州")).add(user::Column::Username.like("%admin%"))
    ).all(&db).await.unwrap();
    println!("查询成功！：{:?}",result)

分页查找

 
use crate::entity::user;
    use entity::user::Entity as UserDao;
    let mut paginator = UserDao::find().filter(
        Condition::all().add(user::Column::Address.eq("郑州")).add(user::Column::Username.like("%admin%"))
    ).paginate(&db,50);
    //paginate(&db,50)此处第二个参数表示设置单页数量，此方法会返回Paginator对象。
    while let Some(user) = paginator.fetch_and_next().await.unwrap() {
    	//循环从paginate取数据，每次取50条，页数加一，直到没有数据
        println!("查询成功！：{:?}",user)
    }

如果直接获取第几页数据怎么做，下面有方法

    use crate::entity::user;
    use entity::user::Entity as UserDao;
    let mut paginator = UserDao::find().filter(
        Condition::all().add(user::Column::Address.eq("郑州")).add(user::Column::Username.like("%admin%"))
    ).paginate(&db,50);
    //此方法可直接取具体页数，注意是从零开始，需要前端页数加一
    let result = paginator.fetch_page(0).await;
    match result{
        Ok(vec_user) => {println!("{:?}", vec_user)}
        Err(_) => {}
    }

修改数据

修改主键为1的用用户名

    use entity::user::Entity as UserDao;
    let user = UserDao::find_by_id(1).one(&db).await.unwrap().unwrap();
    let mut active_model = user.into_active_model();
    active_model.username = ActiveValue::Set("修改后的用户名".to_owned());
    active_model.update(&db).await.unwrap();

如果想强制更新某个字段可以调用。

active_model.reset(user::Column::Address); //这样更新时字段就会强制带上，可以实现把字段置空

删除数据

很简单

    use entity::user::Entity as UserDao;
    let res = UserDao::delete_by_id(1).exec(&db).await.unwrap();

或者还有一种方法

    use entity::user::Entity as UserDao;
    let res = UserDao::find_by_id(1).one(&db).await.unwrap().unwrap();
    let active_model = res.into_active_model();
    active_model.delete(&db).await.unwrap();

数据库事务操作

可以手动调用db的begin和commit方法，以下是官方例子

let txn = db.begin().await?;

bakery::ActiveModel {
    name: Set("SeaSide Bakery".to_owned()),
    profit_margin: Set(10.4),
    ..Default::default()
}
.save(&txn)
.await?;

bakery::ActiveModel {
    name: Set("Top Bakery".to_owned()),
    profit_margin: Set(15.0),
    ..Default::default()
}
.save(&txn)
.await?;

txn.commit().await?;

总结

以上就是sea-orm入门使用教程，更具体的可以查看sea-orm官方文档https://www.sea-ql.org/SeaORM/docs/index/。后续我可能会再出一篇sea-orm的高级使用教程