Getting started with Rust and AWS SAM

• Goals
• Assumptions
• Installing Prerequisits
  • Install Rust
  • Install musl libc tools
    • macOS
    • Linux
  • Install AWS SAM CLI
    • Install the CLI
    • Verify the installation
  • Docker (Optional)
• A note about linking on macOS
• A note on debug and release builds
• A note about the GNU Make Standard Library
• Running
  • Building
  • Deploying
• Inspirations and Sources

Goals

Assumptions

Installing Prerequisits

Install Rust

Install rustup, the Rust installer and version manager. Run the following command and follow the instructions on screen. You should be able to just accept the defaults.

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

To verify the installation was successful run:

cargo --version

And you should see outpup like:

cargo 1.43.0 (2cbe9048e 2020-05-03)

Install musl libc tools

AWS Lambda will run our function in an Amazon Linux Environment. So we will use musl libc "libc" implementaiton so we can staticly link our binaries for running on Lambda. We will use this to eliminates the need an EC2 instance with Amazon Linux to compile our lambda functions.

macOS

The musl libc tools are installed via Homebrew. Please make sure you have it installed before proceeding.

Install the target for musl:

rustup target add x86_64-unknown-linux-musl

Install musl-tools:

brew install filosottile/musl-cross/musl-cross

Linux

Install the target for musl:

rustup target add x86_64-unknown-linux-musl

Install musl-tools:

sudo apt install musl-tools

Install AWS SAM CLI

We require SAM CLI v0.50+. The SAM CLI is installed via Homebrew on both macOS and Linux. Please make sure those are installed and follow these instructions. For full installation details, please see the offical docs.

Install the CLI

brew tap aws/tap
brew install aws-sam-cli

Verify the installation

sam --version

We require version 0.50.0 or greater:

SAM CLI, version 0.51.0

Docker (Optional)

Docker is required for local invocation. However, only a small portion of AWS' infastructure can be simulated locally via Docker. So this can be of limited use.

• macOS installation instructions
• Linux installation instructions

A note about linking on macOS

Under macOS we need to tell cargo about our musl based linker. So we have added a config file in the .cargo directory: .cargo/config

[target.x86_64-unknown-linux-musl]
linker = "x86_64-linux-musl-gcc"

A note on debug and release builds

Currently this project is set to only do debug builds. In the future, I plan the ability to switch between build and debug. And, hopefully, add local debugging.

A note about the GNU Make Standard Library

The files gsml and __gsml are the GNU Make Standard Library or GMSL. They provide useful functions but so far we are only using lc to lowercase strings. This might be overkill when we could be using the stardard shell command tr. But I expect as more functionality is added to this project more will be used. The GMSL is released under the BSD License.

Running

Building

Deploying

Inspirations and Sources

• AWS Lambda Functions written in Rust by Roberto Huertas