107 lines
2.0 KiB
Rust
107 lines
2.0 KiB
Rust
use std::{
|
|
convert::Infallible,
|
|
fmt::Display,
|
|
num::{ParseFloatError, ParseIntError},
|
|
};
|
|
|
|
use crate::ID;
|
|
|
|
/// Cursor type
|
|
///
|
|
/// A custom scalar that serializes as a string.
|
|
/// <https://relay.dev/graphql/connections.htm#sec-Cursor>
|
|
pub trait CursorType: Sized {
|
|
/// Error type for `decode_cursor`.
|
|
type Error: Display;
|
|
|
|
/// Decode cursor from string.
|
|
fn decode_cursor(s: &str) -> Result<Self, Self::Error>;
|
|
|
|
/// Encode cursor to string.
|
|
fn encode_cursor(&self) -> String;
|
|
}
|
|
|
|
impl CursorType for usize {
|
|
type Error = ParseIntError;
|
|
|
|
fn decode_cursor(s: &str) -> Result<Self, Self::Error> {
|
|
s.parse()
|
|
}
|
|
|
|
fn encode_cursor(&self) -> String {
|
|
self.to_string()
|
|
}
|
|
}
|
|
|
|
impl CursorType for i32 {
|
|
type Error = ParseIntError;
|
|
|
|
fn decode_cursor(s: &str) -> Result<Self, Self::Error> {
|
|
s.parse()
|
|
}
|
|
|
|
fn encode_cursor(&self) -> String {
|
|
self.to_string()
|
|
}
|
|
}
|
|
|
|
impl CursorType for i64 {
|
|
type Error = ParseIntError;
|
|
|
|
fn decode_cursor(s: &str) -> Result<Self, Self::Error> {
|
|
s.parse()
|
|
}
|
|
|
|
fn encode_cursor(&self) -> String {
|
|
self.to_string()
|
|
}
|
|
}
|
|
|
|
impl CursorType for String {
|
|
type Error = Infallible;
|
|
|
|
fn decode_cursor(s: &str) -> Result<Self, Self::Error> {
|
|
Ok(s.to_string())
|
|
}
|
|
|
|
fn encode_cursor(&self) -> String {
|
|
self.clone()
|
|
}
|
|
}
|
|
|
|
impl CursorType for ID {
|
|
type Error = Infallible;
|
|
|
|
fn decode_cursor(s: &str) -> Result<Self, Self::Error> {
|
|
Ok(s.to_string().into())
|
|
}
|
|
|
|
fn encode_cursor(&self) -> String {
|
|
self.to_string()
|
|
}
|
|
}
|
|
|
|
impl CursorType for f64 {
|
|
type Error = ParseFloatError;
|
|
|
|
fn decode_cursor(s: &str) -> Result<Self, Self::Error> {
|
|
s.parse()
|
|
}
|
|
|
|
fn encode_cursor(&self) -> String {
|
|
self.to_string()
|
|
}
|
|
}
|
|
|
|
impl CursorType for f32 {
|
|
type Error = ParseFloatError;
|
|
|
|
fn decode_cursor(s: &str) -> Result<Self, Self::Error> {
|
|
s.parse()
|
|
}
|
|
|
|
fn encode_cursor(&self) -> String {
|
|
self.to_string()
|
|
}
|
|
}
|