Bazaar [WIP]

What is this?

Bazaar is a fully async GraphQL Server written in Rust using Actix Web, Async-GraphQL and SQLx. It implements the basic functionality you would expect to find on an e-commerce platform (see functionality.md for more information).

It's my hope that this project will be a useful example for others to see how to compose a production ready Rust application from some of the awesome crates in the ecosystem, along with how various things you would typically see in enterprise applications eg. Testing, Observability, CI etc. can be implemented.

Although this project is intended to be fully functional, certain parts of it will be mocked/stubbed/out-of-scope to keep the bounds on what this side project does reasonable.

I'm still very much learning, so if you spot any issues or have any improvements or feedback on anything within the app, please feel free to drop me a message or raise an issue on the repo.

Tech Stack

See below for a diagram of the architecture as it currently looks. In reality you most probably wouldn't have all of the telemetry backends that are present, however I just wanted to have a go at integrating and playing around with them in this project, so I've left the connections in.

Out of Scope - at least for now

• Stock & Stock Management - Will be included via some stub functionality
• Checkout & Payments - This might be included in the future

Running the App

The app outputs structured json logs, if you want a more human friendly view of them you can download the node-bunyan cli and pipe them through that.

Running the whole app within docker-compose

There is a demo docker-compose file within the repository that should handle setting up all dependencies and the application within the docker environment. It can be run with:

docker-compose -f docker-compose.demo.yaml up

Running dependencies in docker-compose and running the app via Rust

If you want to run all of the dependencies in docker, but the app with rust, you can use the docker-compose.yaml file. Once the docker-compose has spun up, migrate the database by running SKIP_DOCKER=true ./scripts/init_db.sh. Once the migration has finished the application can then be run with cargo run --bin app.

Minimal dependencies directly via docker

The minimum dependencies the app requires is a running instance of Postgres, the easiest way to set this up is to run the ./scripts/init_db.sh script, which will pull down the latest docker postgres image, start it up, and run the migrations.

You can then run the actual application with cargo run --bin app.

Docker

docker build --tag bazaar --file Dockerfile .
docker run -p 8000:8000 bazaar

Environment Variables

Most environment variables are managed through configuration files found within the configuration directory, however some that are not included in there (and need to be set up manually in order to run the application) can be found below

CI

The CI pipeline includes checks on sqlx-data.json, if it detects that there have been changes without updating this file it will fail CI. See preparing for SQLx offline below for more details.

GraphQL Schema Generation

Although it's not pretty there's a small binary in the workspace which can be used to generate the graphql schema for the application and write it to schema.graphql. To do so just run cargo run --bin schema. The easiest way to keep it up to date is to create a basic pre-commit hook to run it for you.

Tooling

Testing

A majority of the functionality are tested through integration tests, found in the /tests directory. This is to ensure the public API that's exposed behaves as intended.

As all authentication is done through HttpOnly cookies, you'll generally see a pattern where different HTTP Clients (currently reqwest) are set up throughout the tests, with the client holding the auth cookies as appropriate

Helpful Notes

Generating RSA Keys

Using OpenSSL to generate key pairs: replace what's in the <>

Private & Public Key Pair

openssl genpkey -out <name>.pem -algorithm RSA -pkeyopt rsa_keygen_bits:<len>

Extracting Public key

openssl rsa -in <name>.pem -pubout > <name>.pub

Database Migrations

Creating Migrations

# Ensure $DATABASE_URL is correctly set
sqlx migrate add <migration name>

Running Migrations

These are set up to run manually with ./scripts/init_db.sh, optionally you can pass a skip variable if a docker instance is already running SKIP_DOCKER=true ./scripts/init_db.sh

If you need to run them manually, you can do so with the sqlx CLI:

sqlx migrate run

Preparing for SQLX offline

CI will fail if the offline SQLX schema hasn't been updated when it should have been. Again it's probably useful to add this as a pre-commit hook on the project

cargo sqlx prepare -- --lib

Useful resources if you want to build something similar

• Luca Palmieri's - Zero to Production In Rust: This is a great resource that I would highly recommend if you're interested in Rust at all, but particularly if you're interested in building Web Applications/APIs