ensure a consistent style for all changes

.rustfmt.toml

@@ -1,2 +1,4 @@
+# https://github.com/rust-lang/rustfmt/blob/master/Configurations.md#merge_imports
 merge_imports = true
+# https://github.com/rust-lang/rustfmt/blob/master/Configurations.md#max_width
 max_width = 120

.travis.yml

@@ -7,6 +7,12 @@ cache:
 before_cache:
   - rm -rf /home/travis/.cargo/registry
 
+install: |
+  # this project's rustfmt style requires nightly features
+  if [[ "$TRAVIS_RUST_VERSION" == nightly ]]; then
+    rustup component add rustfmt
+  fi
+
 matrix:
   include:
   - rust: 1.31.0
@@ -18,5 +24,9 @@ matrix:
   - env: TARGET=x86_64-unknown-linux-musl
   - env: TARGET=x86_64-unknown-linux-gnu
 script:
+  - |
+    if [[ "$TRAVIS_RUST_VERSION" == nightly ]]; then
+      cargo fmt --all -- --check
+    fi
   - cargo build --verbose --all
   - cargo test --verbose --all

CONTRIBUTING.md

@@ -1,17 +1,17 @@
 # Contributing Guidelines
 
-Thank you for your interest in contributing to our project. Whether it's a bug report, new feature, correction, or additional 
+Thank you for your interest in contributing to our project. Whether it's a bug report, new feature, correction, or additional
 documentation, we greatly value feedback and contributions from our community.
 
-Please read through this document before submitting any issues or pull requests to ensure we have all the necessary 
+Please read through this document before submitting any issues or pull requests to ensure we have all the necessary
 information to effectively respond to your bug report or contribution.
 
 
 ## Reporting Bugs/Feature Requests
 
 We welcome you to use the GitHub issue tracker to report bugs or suggest features.
 
-When filing an issue, please check [existing open](https://github.com/awslabs/aws-lambda-rust-runtime/issues), or [recently closed](https://github.com/awslabs/aws-lambda-rust-runtime/issues?utf8=%E2%9C%93&q=is%3Aissue%20is%3Aclosed%20), issues to make sure somebody else hasn't already 
+When filing an issue, please check [existing open](https://github.com/awslabs/aws-lambda-rust-runtime/issues), or [recently closed](https://github.com/awslabs/aws-lambda-rust-runtime/issues?utf8=%E2%9C%93&q=is%3Aissue%20is%3Aclosed%20), issues to make sure somebody else hasn't already
 reported the issue. Please try to include as much information as you can. Details like these are incredibly useful:
 
 * A reproducible test case or series of steps
@@ -32,21 +32,21 @@ To send us a pull request, please:
 1. Fork the repository.
 2. Modify the source; please focus on the specific change you are contributing. If you also reformat all the code, it will be hard for us to focus on your change.
 3. Ensure local tests pass.
-4. Commit to your fork using clear commit messages.
+4. Commit to your fork using clear commit messages and ensure any Rust source files have been formatted with the [rustfmt tool](https://github.com/rust-lang/rustfmt#quick-start)
 5. Send us a pull request, answering any default questions in the pull request interface.
 6. Pay attention to any automated CI failures reported in the pull request, and stay involved in the conversation.
 
-GitHub provides additional document on [forking a repository](https://help.github.com/articles/fork-a-repo/) and 
+GitHub provides additional document on [forking a repository](https://help.github.com/articles/fork-a-repo/) and
 [creating a pull request](https://help.github.com/articles/creating-a-pull-request/).
 
 
 ## Finding contributions to work on
-Looking at the existing issues is a great way to find something to contribute on. As our projects, by default, use the default GitHub issue labels (enhancement/bug/duplicate/help wanted/invalid/question/wontfix), looking at any ['help wanted'](https://github.com/awslabs/aws-lambda-rust-runtime/labels/help%20wanted) issues is a great place to start. 
+Looking at the existing issues is a great way to find something to contribute on. As our projects, by default, use the default GitHub issue labels (enhancement/bug/duplicate/help wanted/invalid/question/wontfix), looking at any ['help wanted'](https://github.com/awslabs/aws-lambda-rust-runtime/labels/help%20wanted) issues is a great place to start.
 
 
 ## Code of Conduct
-This project has adopted the [Amazon Open Source Code of Conduct](https://aws.github.io/code-of-conduct). 
-For more information see the [Code of Conduct FAQ](https://aws.github.io/code-of-conduct-faq) or contact 
+This project has adopted the [Amazon Open Source Code of Conduct](https://aws.github.io/code-of-conduct).
+For more information see the [Code of Conduct FAQ](https://aws.github.io/code-of-conduct-faq) or contact
 [email protected] with any additional questions or comments.
 
 

lambda-http/src/ext.rs

@@ -6,8 +6,7 @@ use serde::{de::value::Error as SerdeError, Deserialize};
 use serde_json;
 use serde_urlencoded;
 
-use crate::request::RequestContext;
-use crate::strmap::StrMap;
+use crate::{request::RequestContext, strmap::StrMap};
 
 /// API gateway pre-parsed http query string parameters
 pub(crate) struct QueryStringParameters(pub(crate) StrMap);
@@ -157,9 +156,7 @@ mod tests {
     use serde_derive::Deserialize;
     use std::collections::HashMap;
 
-    use crate::GatewayRequest;
-    use crate::RequestExt;
-    use crate::StrMap;
+    use crate::{GatewayRequest, RequestExt, StrMap};
 
     #[test]
     fn requests_have_query_string_ext() {

lambda-http/src/lib.rs

@@ -55,12 +55,8 @@ pub mod request;
 mod response;
 mod strmap;
 
-pub use crate::body::Body;
-pub use crate::ext::RequestExt;
-use crate::request::GatewayRequest;
-use crate::response::GatewayResponse;
-pub use crate::response::IntoResponse;
-pub use crate::strmap::StrMap;
+pub use crate::{body::Body, ext::RequestExt, response::IntoResponse, strmap::StrMap};
+use crate::{request::GatewayRequest, response::GatewayResponse};
 
 /// Type alias for `http::Request`s with a fixed `lambda_http::Body` body
 pub type Request = http::Request<Body>;

lambda-http/src/request.rs

@@ -15,9 +15,11 @@ use serde::{
 use serde_derive::Deserialize;
 use serde_json::Value;
 
-use crate::body::Body;
-use crate::ext::{PathParameters, QueryStringParameters, StageVariables};
-use crate::strmap::StrMap;
+use crate::{
+    body::Body,
+    ext::{PathParameters, QueryStringParameters, StageVariables},
+    strmap::StrMap,
+};
 
 /// Representation of an API Gateway proxy event data
 #[doc(hidden)]

lambda-runtime/src/context.rs

@@ -4,8 +4,7 @@ use backtrace;
 use chrono::Utc;
 use lambda_runtime_client;
 
-use crate::env as lambda_env;
-use crate::error::HandlerError;
+use crate::{env as lambda_env, error::HandlerError};
 
 /// The Lambda function execution context. The values in this struct
 /// are populated using the [Lambda environment variables](https://docs.aws.amazon.com/lambda/latest/dg/current-supported-versions.html)

lambda-runtime/src/env.rs

@@ -88,8 +88,7 @@ impl ConfigProvider for EnvConfigProvider {
 
 #[cfg(test)]
 pub(crate) mod tests {
-    use crate::env::*;
-    use crate::error;
+    use crate::{env::*, error};
     use std::{env, error::Error};
 
     pub(crate) struct MockConfigProvider {

lambda-runtime/src/lib.rs

@@ -83,6 +83,4 @@ mod env;
 pub mod error;
 mod runtime;
 
-pub use crate::context::*;
-pub use crate::error::HandlerError;
-pub use crate::runtime::*;
+pub use crate::{context::*, error::HandlerError, runtime::*};

lambda-runtime/src/runtime.rs

@@ -5,9 +5,11 @@ use serde;
 use serde_json;
 use tokio::runtime::Runtime as TokioRuntime;
 
-use crate::context::Context;
-use crate::env::{ConfigProvider, EnvConfigProvider, FunctionSettings};
-use crate::error::{HandlerError, RuntimeError};
+use crate::{
+    context::Context,
+    env::{ConfigProvider, EnvConfigProvider, FunctionSettings},
+    error::{HandlerError, RuntimeError},
+};
 
 const MAX_RETRIES: i8 = 3;
 
@@ -323,8 +325,7 @@ where
 #[cfg(test)]
 pub(crate) mod tests {
     use super::*;
-    use crate::context;
-    use crate::env;
+    use crate::{context, env};
     use lambda_runtime_client::RuntimeClient;
 
     #[test]