[−][src]Trait async_graphql::ScalarType

pub trait ScalarType: Sized + Send {
    fn parse(value: Value) -> InputValueResult<Self>;
    fn to_value(&self) -> Value;

    fn is_valid(_value: &Value) -> bool { ... }
}

Represents a GraphQL scalar

You can implement the trait to create a custom scalar.

Examples

use async_graphql::*;

struct MyInt(i32);

#[Scalar]
impl ScalarType for MyInt {
    fn parse(value: Value) -> InputValueResult<Self> {
        if let Value::Int(n) = value {
            Ok(MyInt(n as i32))
        } else {
            Err(InputValueError::ExpectedType(value))
        }
    }

    fn to_value(&self) -> Value {
        Value::Int(self.0)
    }
}

Required methods

`fn parse(value: Value) -> InputValueResult<Self>`

Parse a scalar value, return Some(Self) if successful, otherwise return None.

`fn to_value(&self) -> Value`

Convert the scalar to Value.

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Provided methods

`fn is_valid(_value: &Value) -> bool`

Checks for a valid scalar value.

Implementing this function can find incorrect input values during the verification phase, which can improve performance.

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Implementations on Foreign Types

`impl ScalarType for bool`[src]

The Boolean scalar type represents true or false.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn is_valid(value: &Value) -> bool`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for DateTime<Utc>`[src]

Implement the DateTime scalar

The input/output is a string in RFC3339 format.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for f32`[src]

The Float scalar type represents signed double-precision fractional values as specified by IEEE 754.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn is_valid(value: &Value) -> bool`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for f64`[src]

The Float scalar type represents signed double-precision fractional values as specified by IEEE 754.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn is_valid(value: &Value) -> bool`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for i8`[src]

The Int scalar type represents non-fractional signed whole numeric values. Int can represent values between -(2^31) and 2^31 - 1.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn is_valid(value: &Value) -> bool`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for i16`[src]

The Int scalar type represents non-fractional signed whole numeric values. Int can represent values between -(2^31) and 2^31 - 1.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn is_valid(value: &Value) -> bool`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for i32`[src]

The Int scalar type represents non-fractional signed whole numeric values. Int can represent values between -(2^31) and 2^31 - 1.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn is_valid(value: &Value) -> bool`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for u8`[src]

The Int scalar type represents non-fractional signed whole numeric values. Int can represent values between -(2^31) and 2^31 - 1.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn is_valid(value: &Value) -> bool`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for u16`[src]

The Int scalar type represents non-fractional signed whole numeric values. Int can represent values between -(2^31) and 2^31 - 1.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn is_valid(value: &Value) -> bool`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for i64`[src]

The Int64 scalar type represents non-fractional signed whole numeric values. Int can represent values between -(2^64) and 2^64 - 1.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn is_valid(value: &Value) -> bool`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for u64`[src]

The Int64 scalar type represents non-fractional signed whole numeric values. Int can represent values between -(2^64) and 2^64 - 1.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn is_valid(value: &Value) -> bool`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for NaiveDate`[src]

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for NaiveTime`[src]

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for String`[src]

The String scalar type represents textual data, represented as UTF-8 character sequences. The String type is most often used by GraphQL to represent free-form human-readable text.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn is_valid(value: &Value) -> bool`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for Uuid`[src]

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for ObjectId`[src]

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for UtcDateTime`[src]

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for Url`[src]

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn to_value(&self) -> Value`[src]

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Implementors

`impl ScalarType for Any`[src]

The _Any scalar is used to pass representations of entities from external services into the root _entities field for execution.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn is_valid(_value: &Value) -> bool`[src]

`fn to_value(&self) -> Value`[src]

`impl ScalarType for ID`[src]

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn is_valid(value: &Value) -> bool`[src]

`fn to_value(&self) -> Value`[src]

`impl<T: DeserializeOwned + Serialize + Send + Sync> ScalarType for Json<T>`[src]

A scalar that can represent any JSON value.

`fn parse(value: Value) -> InputValueResult<Self>`[src]

`fn to_value(&self) -> Value`[src]

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