async-graphql/src/types/enum.rs
2020-05-16 21:14:26 +08:00

44 lines
1.2 KiB
Rust

use crate::{InputValueError, InputValueResult, Result, Type, Value};
#[allow(missing_docs)]
pub struct EnumItem<T> {
pub name: &'static str,
pub value: T,
}
#[allow(missing_docs)]
#[async_trait::async_trait]
pub trait EnumType: Type + Sized + Eq + Send + Copy + Sized + 'static {
fn items() -> &'static [EnumItem<Self>];
fn parse_enum(value: Value) -> InputValueResult<Self> {
let value = match &value {
Value::Enum(s) => s,
Value::String(s) => s.as_str(),
_ => return Err(InputValueError::ExpectedType(value)),
};
let items = Self::items();
for item in items {
if item.name == value {
return Ok(item.value);
}
}
Err(InputValueError::Custom(format!(
r#"Enumeration type "{}" does not contain the value "{}""#,
Self::type_name(),
value
)))
}
fn resolve_enum(&self) -> Result<serde_json::Value> {
let items = Self::items();
for item in items {
if item.value == *self {
return Ok(item.name.into());
}
}
unreachable!()
}
}