Trait juniper::integrations::chrono::FromFixedOffset

pub trait FromFixedOffset: TimeZone {
    // Required method
    fn from_fixed_offset(dt: DateTime<FixedOffset>) -> DateTime<Self>;
}

Trait allowing to implement a custom TimeZone, which preserves its TimeZone information when parsed in a DateTime GraphQL scalar.

Example

Creating a custom CET TimeZone using chrono-tz crate. This is required because chrono-tz uses enum to represent all TimeZones, so we have no knowledge of the concrete underlying TimeZone on the type level.

#[derive(Clone, Copy)]
struct CET;

impl TimeZone for CET {
    type Offset = <chrono_tz::Tz as TimeZone>::Offset;

    fn from_offset(_: &Self::Offset) -> Self {
        CET
    }

    fn offset_from_local_date(
        &self,
        local: &chrono::NaiveDate,
    ) -> chrono::LocalResult<Self::Offset> {
        chrono_tz::CET.offset_from_local_date(local)
    }

    fn offset_from_local_datetime(
        &self,
        local: &chrono::NaiveDateTime,
    ) -> chrono::LocalResult<Self::Offset> {
        chrono_tz::CET.offset_from_local_datetime(local)
    }

    fn offset_from_utc_date(&self, utc: &chrono::NaiveDate) -> Self::Offset {
        chrono_tz::CET.offset_from_utc_date(utc)
    }

    fn offset_from_utc_datetime(&self, utc: &chrono::NaiveDateTime) -> Self::Offset {
        chrono_tz::CET.offset_from_utc_datetime(utc)
    }
}

impl FromFixedOffset for CET {
    fn from_fixed_offset(dt: DateTime<FixedOffset>) -> DateTime<Self> {
        dt.with_timezone(&CET)
    }
}

struct Root;

#[graphql_object]
impl Root {
    fn pass_date_time(dt: DateTime<CET>) -> DateTime<CET> {
        dt
    }
}

Required Methods

fn from_fixed_offset(dt: DateTime<FixedOffset>) -> DateTime<Self>

Converts the given DateTime<FixedOffset> into a DateTime<Self>.

Object Safety

This trait is not object safe.

Implementations on Foreign Types

impl FromFixedOffset for Tz

fn from_fixed_offset(dt: DateTime<FixedOffset>) -> DateTime<Self>

impl FromFixedOffset for FixedOffset

fn from_fixed_offset(dt: DateTime<Self>) -> DateTime<Self>

impl FromFixedOffset for Local

fn from_fixed_offset(dt: DateTime<FixedOffset>) -> DateTime<Self>

impl FromFixedOffset for Utc

fn from_fixed_offset(dt: DateTime<FixedOffset>) -> DateTime<Self>

Implementors