sea-orm/src/entity/active_enum.rs
Billy Chan 388bf2cfca
Fixup
2021-10-20 15:17:11 +08:00

276 lines
8.9 KiB
Rust

use crate::{ColumnDef, DbErr, TryGetable};
use sea_query::{Nullable, Value, ValueType};
/// A Rust representation of enum defined in database.
///
/// # Implementations
///
/// You can implement [ActiveEnum] manually by hand or use the derive macro [DeriveActiveEnum](sea_orm_macros::DeriveActiveEnum).
///
/// # Examples
///
/// Implementing it manually versus using the derive macro [DeriveActiveEnum](sea_orm_macros::DeriveActiveEnum).
///
/// > See [DeriveActiveEnum](sea_orm_macros::DeriveActiveEnum) for the full specification of macro attributes.
///
/// ```rust
/// use sea_orm::entity::prelude::*;
///
/// // Using the derive macro
/// #[derive(Debug, PartialEq, DeriveActiveEnum)]
/// #[sea_orm(rs_type = "String", db_type = "String(Some(1))")]
/// pub enum DeriveCategory {
/// #[sea_orm(string_value = "B")]
/// Big,
/// #[sea_orm(string_value = "S")]
/// Small,
/// }
///
/// // Implementing it manually
/// #[derive(Debug, PartialEq)]
/// pub enum Category {
/// Big,
/// Small,
/// }
///
/// impl ActiveEnum for Category {
/// // The macro attribute `rs_type` is being pasted here
/// type Value = String;
///
/// // Will be atomically generated by `DeriveActiveEnum`
/// fn to_value(&self) -> Self::Value {
/// match self {
/// Self::Big => "B",
/// Self::Small => "S",
/// }
/// .to_owned()
/// }
///
/// // Will be atomically generated by `DeriveActiveEnum`
/// fn try_from_value(v: &Self::Value) -> Result<Self, DbErr> {
/// match v.as_ref() {
/// "B" => Ok(Self::Big),
/// "S" => Ok(Self::Small),
/// _ => Err(DbErr::Query(format!(
/// "unexpected value for Category enum: {}",
/// v
/// ))),
/// }
/// }
///
/// fn db_type() -> ColumnDef {
/// // The macro attribute `db_type` is being pasted here
/// ColumnType::String(Some(1)).def()
/// }
/// }
/// ```
///
/// Using [ActiveEnum] on Model.
///
/// ```
/// use sea_orm::entity::prelude::*;
///
/// // Define the `Category` active enum
/// #[derive(Debug, Clone, PartialEq, DeriveActiveEnum)]
/// #[sea_orm(rs_type = "String", db_type = "String(Some(1))")]
/// pub enum Category {
/// #[sea_orm(string_value = "B")]
/// Big,
/// #[sea_orm(string_value = "S")]
/// Small,
/// }
///
/// #[derive(Clone, Debug, PartialEq, DeriveEntityModel)]
/// #[sea_orm(table_name = "active_enum")]
/// pub struct Model {
/// #[sea_orm(primary_key)]
/// pub id: i32,
/// // Represents a db column using `Category` active enum
/// pub category: Category,
/// pub category_opt: Option<Category>,
/// }
///
/// #[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
/// pub enum Relation {}
///
/// impl ActiveModelBehavior for ActiveModel {}
/// ```
pub trait ActiveEnum: Sized {
/// Define the Rust type that each enum variant represents.
type Value: Into<Value> + ValueType + Nullable + TryGetable;
/// Convert enum variant into the corresponding value.
fn to_value(&self) -> Self::Value;
/// Try to convert the corresponding value into enum variant.
fn try_from_value(v: &Self::Value) -> Result<Self, DbErr>;
/// Get the database column definition of this active enum.
fn db_type() -> ColumnDef;
}
#[cfg(test)]
mod tests {
use crate as sea_orm;
use crate::{entity::prelude::*, *};
use pretty_assertions::assert_eq;
#[test]
fn active_enum_string() {
#[derive(Debug, PartialEq)]
pub enum Category {
Big,
Small,
}
impl ActiveEnum for Category {
type Value = String;
fn to_value(&self) -> Self::Value {
match self {
Self::Big => "B",
Self::Small => "S",
}
.to_owned()
}
fn try_from_value(v: &Self::Value) -> Result<Self, DbErr> {
match v.as_ref() {
"B" => Ok(Self::Big),
"S" => Ok(Self::Small),
_ => Err(DbErr::Query(format!(
"unexpected value for Category enum: {}",
v
))),
}
}
fn db_type() -> ColumnDef {
ColumnType::String(Some(1)).def()
}
}
#[derive(Debug, PartialEq, DeriveActiveEnum)]
#[sea_orm(rs_type = "String", db_type = "String(Some(1))")]
pub enum DeriveCategory {
#[sea_orm(string_value = "B")]
Big,
#[sea_orm(string_value = "S")]
Small,
}
assert_eq!(Category::Big.to_value(), "B".to_owned());
assert_eq!(Category::Small.to_value(), "S".to_owned());
assert_eq!(DeriveCategory::Big.to_value(), "B".to_owned());
assert_eq!(DeriveCategory::Small.to_value(), "S".to_owned());
assert_eq!(
Category::try_from_value(&"A".to_owned()).err(),
Some(DbErr::Query(
"unexpected value for Category enum: A".to_owned()
))
);
assert_eq!(
Category::try_from_value(&"B".to_owned()).ok(),
Some(Category::Big)
);
assert_eq!(
Category::try_from_value(&"S".to_owned()).ok(),
Some(Category::Small)
);
assert_eq!(
DeriveCategory::try_from_value(&"A".to_owned()).err(),
Some(DbErr::Query(
"unexpected value for DeriveCategory enum: A".to_owned()
))
);
assert_eq!(
DeriveCategory::try_from_value(&"B".to_owned()).ok(),
Some(DeriveCategory::Big)
);
assert_eq!(
DeriveCategory::try_from_value(&"S".to_owned()).ok(),
Some(DeriveCategory::Small)
);
assert_eq!(Category::db_type(), ColumnType::String(Some(1)).def());
assert_eq!(DeriveCategory::db_type(), ColumnType::String(Some(1)).def());
}
#[test]
fn active_enum_derive_signed_integers() {
macro_rules! test_int {
($ident: ident, $rs_type: expr, $db_type: expr, $col_def: ident) => {
#[derive(Debug, PartialEq, DeriveActiveEnum)]
#[sea_orm(rs_type = $rs_type, db_type = $db_type)]
pub enum $ident {
#[sea_orm(num_value = 1)]
Big,
#[sea_orm(num_value = 0)]
Small,
#[sea_orm(num_value = -10)]
Negative,
}
assert_eq!($ident::Big.to_value(), 1);
assert_eq!($ident::Small.to_value(), 0);
assert_eq!($ident::Negative.to_value(), -10);
assert_eq!($ident::try_from_value(&1).ok(), Some($ident::Big));
assert_eq!($ident::try_from_value(&0).ok(), Some($ident::Small));
assert_eq!($ident::try_from_value(&-10).ok(), Some($ident::Negative));
assert_eq!(
$ident::try_from_value(&2).err(),
Some(DbErr::Query(format!(
"unexpected value for {} enum: 2",
stringify!($ident)
)))
);
assert_eq!($ident::db_type(), ColumnType::$col_def.def());
};
}
test_int!(I8, "i8", "TinyInteger", TinyInteger);
test_int!(I16, "i16", "SmallInteger", SmallInteger);
test_int!(I32, "i32", "Integer", Integer);
test_int!(I64, "i64", "BigInteger", BigInteger);
}
#[test]
fn active_enum_derive_unsigned_integers() {
macro_rules! test_uint {
($ident: ident, $rs_type: expr, $db_type: expr, $col_def: ident) => {
#[derive(Debug, PartialEq, DeriveActiveEnum)]
#[sea_orm(rs_type = $rs_type, db_type = $db_type)]
pub enum $ident {
#[sea_orm(num_value = 1)]
Big,
#[sea_orm(num_value = 0)]
Small,
}
assert_eq!($ident::Big.to_value(), 1);
assert_eq!($ident::Small.to_value(), 0);
assert_eq!($ident::try_from_value(&1).ok(), Some($ident::Big));
assert_eq!($ident::try_from_value(&0).ok(), Some($ident::Small));
assert_eq!(
$ident::try_from_value(&2).err(),
Some(DbErr::Query(format!(
"unexpected value for {} enum: 2",
stringify!($ident)
)))
);
assert_eq!($ident::db_type(), ColumnType::$col_def.def());
};
}
test_uint!(U8, "u8", "TinyInteger", TinyInteger);
test_uint!(U16, "u16", "SmallInteger", SmallInteger);
test_uint!(U32, "u32", "Integer", Integer);
test_uint!(U64, "u64", "BigInteger", BigInteger);
}
}