Trait LocalContext 

pub trait LocalContext<Msg>: Sized {
    // Required methods
    fn from_local<'async_trait>(    ) -> Pin<Box<dyn Future<Output = Result<Self>> + Send + 'async_trait>>
       where Self: 'async_trait;
    fn msg<'life0, 'async_trait>(
        &'life0 self,
    ) -> Pin<Box<dyn Future<Output = Result<Msg>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait;
}

A trait of the Context type, required when using run_local_handler to execute the message handler.

All Context types must implement the implement the LocalContext::from_local and LocalContext::msg methods for their corresponding Msg type in order to use the Context with run_local_handler.

Example

use anyhow::Result;
use serde::Deserialize;
use cobalt_aws::lambda::LocalContext;

/// Shared context we build up before invoking the local runner.
#[derive(Debug)]
pub struct Context {
    pub greeting: String,
}

#[derive(Debug, Deserialize)]
pub struct Message {
    pub target: String,
}

#[async_trait]
impl LocalContext<Message> for Context {
    /// Initialise a shared context object from which will be
    /// passed to all instances of the message handler.
    async fn from_local() -> Result<Self> {
        Ok(Context {
            greeting: "Hello".to_string(),
        })
    }

    /// Construct a message object to be processed by the message handler.
    async fn msg(&self) -> Result<Message> {
        Ok(Message {
            target: "World".to_string(),
        })
    }
}

Required Methods

fn from_local<'async_trait>() -> Pin<Box<dyn Future<Output = Result<Self>> + Send + 'async_trait>>

where Self: 'async_trait,

Construct a new local Context object.

fn msg<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Result<Msg>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Construct a message object to be processed by the message handler.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors