Migrate lambda-runtime-client to Rust 2018 (#36)

* Migrate lambda-runtime-client to Rust 2018
* Require Rust 1.31 as a minimum.

Author: Sh4rK

.travis.yml

@@ -9,7 +9,7 @@ before_cache:
 
 matrix:
   include:
-  - rust: 1.30.0
+  - rust: 1.31.0
   - rust: stable
   - rust: beta
   - rust: nightly

README.md

@@ -10,7 +10,7 @@ This package makes it easy to run AWS Lambda Functions written in Rust. This wor
 
 ## Example function
 
-The code below creates a simple function that receives an event with a `greeting` and `name` field and returns a `GreetingResponse` message for the given name and greeting. Notice: to run these examples, we require a minimum Rust version of 1.30.
+The code below creates a simple function that receives an event with a `greeting` and `name` field and returns a `GreetingResponse` message for the given name and greeting. Notice: to run these examples, we require a minimum Rust version of 1.31.
 
 ```rust,no_run
 extern crate lambda_runtime as lambda;

lambda-runtime-client/Cargo.toml

@@ -2,6 +2,7 @@
 name = "lambda_runtime_client"
 version = "0.1.0"
 authors = ["Stefano Buliani", "David Barsky"]
+edition = "2018"
 description = "Client SDK for AWS Lambda's runtime APIs"
 keywords = ["AWS", "Lambda", "Runtime", "API", "Client"]
 license = "Apache-2.0"

lambda-runtime-client/src/client.rs

@@ -1,14 +1,17 @@
-use error::{ApiError, ErrorResponse, RuntimeApiError};
+use std::{collections::HashMap, fmt};
+
 use hyper::{
     client::HttpConnector,
     header::{self, HeaderMap, HeaderValue},
     rt::{Future, Stream},
     Body, Client, Method, Request, Uri,
 };
+use serde_derive::Deserialize;
 use serde_json;
-use std::{collections::HashMap, fmt};
 use tokio::runtime::Runtime;
 
+use crate::error::{ApiError, ErrorResponse, RuntimeApiError};
+
 const RUNTIME_API_VERSION: &str = "2018-06-01";
 const API_CONTENT_TYPE: &str = "application/json";
 const API_ERROR_CONTENT_TYPE: &str = "application/vnd.aws.lambda.error+json";
@@ -48,7 +51,7 @@ impl LambdaHeaders {
 }
 
 impl fmt::Display for LambdaHeaders {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.write_str(self.as_str())
     }
 }
@@ -257,7 +260,7 @@ impl RuntimeClient {
     ///
     /// # Returns
     /// A `Result` object containing a bool return value for the call or an `error::ApiError` instance.
-    pub fn event_error(&self, request_id: &str, e: &RuntimeApiError) -> Result<(), ApiError> {
+    pub fn event_error(&self, request_id: &str, e: &dyn RuntimeApiError) -> Result<(), ApiError> {
         let uri: Uri = format!(
             "http://{}/{}/runtime/invocation/{}/error",
             self.endpoint, RUNTIME_API_VERSION, request_id
@@ -304,7 +307,7 @@ impl RuntimeClient {
     /// # Panics
     /// If it cannot send the init error. In this case we panic to force the runtime
     /// to restart.
-    pub fn fail_init(&self, e: &RuntimeApiError) {
+    pub fn fail_init(&self, e: &dyn RuntimeApiError) {
         let uri: Uri = format!("http://{}/{}/runtime/init/error", self.endpoint, RUNTIME_API_VERSION)
             .parse()
             .expect("Could not generate Runtime URI");

lambda-runtime-client/src/error.rs

@@ -6,6 +6,7 @@ use std::{env, error::Error, fmt, io, num::ParseIntError, option::Option};
 use backtrace;
 use http::{header::ToStrError, uri::InvalidUri};
 use hyper;
+use serde_derive::Serialize;
 use serde_json;
 
 /// Error type description for the `ErrorResponse` event. This type should be returned
@@ -118,7 +119,7 @@ impl ApiError {
 }
 
 impl fmt::Display for ApiError {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "{}", self.msg)
     }
 }
@@ -129,7 +130,7 @@ impl Error for ApiError {
         &self.msg
     }
 
-    fn cause(&self) -> Option<&Error> {
+    fn cause(&self) -> Option<&dyn Error> {
         // Generic error, underlying cause isn't tracked.
         None
     }

lambda-runtime-client/src/lib.rs

@@ -58,17 +58,7 @@
 
 #[macro_use]
 extern crate log;
-#[macro_use]
-extern crate serde_derive;
-
-extern crate backtrace;
-extern crate http;
-extern crate hyper;
-extern crate serde;
-extern crate serde_json;
-extern crate tokio;
 
 mod client;
 pub mod error;
-
-pub use client::*;
+pub use crate::client::*;