Merge pull request #239 from RMoodsTeam/232-bug-setup-dev-database

232: Dev database setup

backend/.gitignore

@@ -1,5 +1,6 @@
 # Environment variables
 .env
+.env.prod
 
 # Generated by Cargo
 # will have compiled files and executables

backend/README.md

@@ -1,31 +1,104 @@
 # RMoods Backend
 
 ## Build
+
 For deployment, append the `release` flag.
+
 ```sh
 cargo build
 ```
 
-
 ## Run
+
+To run in debug mode, using the `.env` file:
+
 ```sh
 cargo run
 ```
-### Environment
-Your `.env` file should look like this:
+
+To run in release mode, using the `.env.prod` file, just add the `--release` flag.
+**Be careful! Using the production DB for development is forbidden**
+
+```sh
+cargo run --release
+```
+
+## Local Environment
+
+Your `.env` file should have all the properties as listed in the `.env.example` file.
+Don't worry, the server verifies the presence of these variables at startup.
+
+[Docker Desktop](https://www.docker.com/products/docker-desktop/) is recommended, as it's really easy to manage
+containers there.
+
+### Database setup
+
+You'll need a local PostgreSQL database to run the backend and not cause any trouble with the production DB.
+
+First, download the image that matches our production database version.
+
+```sh
+docker pull postgres:15.10
+```
+
+Create a docker volume to persist the data between container runs.
+
+```sh
+docker volume create rmoods-dev-pgdata
+```
+
+Run the container with the volume mounted.
+
+```sh
+docker run --name rmoods-dev-db -p 8003:5432 -e POSTGRES_USER=rmoods-dev -e POSTGRES_PASSWORD=mypasswd -e POSTGRES_DB=rmoods -v rmoods-dev-pgdata:/var/lib/postgresql/data postgres:15.10 
+```
+
+Add this to your `.env` file:
+
+```sh
+DATABASE_URL=postgres://rmoods-dev:mypasswd@localhost:8003/rmoods-db
 ```
-CLIENT_ID=***
-CLIENT_SECRET=***
-DATABASE_URL=***
+
+The production DB URL is kept only in `.env.prod`.
+
+To restart the container afterward:
+
+```sh
+docker start rmoods-dev-db --attach
 ```
 
+With that, you should have a local database running. Now you need to configure it to match our backend code and data
+schema.
+
+### SQLx CLI
+
+To maintain your local database, you need to use the `sqlx` CLI tool from time to time.
+Refer to the [SQLx CLI documentation](https://github.com/launchbadge/sqlx/blob/main/sqlx-cli/README.md).
+Just to get you started:
+
+```sh
+sqlx database create
+sqlx migrate run
+```
+
+Whenever we change the schema, you need to keep the local DB in sync. You can just drop the database and recreate it.
+
+```sh
+sqlx database drop
+sqlx database create
+sqlx migrate run
+```
 
 ## Docker
+
 Backend for RMoods can be run a Docker container.
+
 ```Dockerfile
 docker build -t rmoods-backend .
 ```
+
 After it's done building, run the container. You may want to map the default 8001 port to 9001 for differentiation.
+
 ```Dockerfile
 docker run -p 9001:8001 rmoods-backend
 ```

backend/src/main.rs

@@ -1,9 +1,10 @@
+use crate::env::DATABASE_URL;
 use crate::db::db_client::DbClient;
 use crate::fetcher::fetcher::RMoodsFetcher;
 use crate::fetcher::reddit::connection::RedditConnection;
 use crate::nlp::nlp_client::NlpClient;
 use crate::open_api::ApiDoc;
-use crate::startup::{shutdown_signal, verify_environment};
+use crate::startup::{setup_environment, shutdown_signal, verify_environment};
 use crate::websocket::SystemMessage;
 use axum::Router;
 use log::{error, info, warn};
@@ -44,7 +45,7 @@ pub struct AppState {
 
 /// Run the server, assuming the environment has been already validated.
 async fn run() -> anyhow::Result<()> {
-    let url = std::env::var("DATABASE_URL").expect("DB_URL is set");
+    let url = std::env::var(DATABASE_URL).expect("DB_URL is set");
     let pool = PgPoolOptions::new()
         .max_connections(10)
         .connect(&url)
@@ -116,16 +117,14 @@ async fn run() -> anyhow::Result<()> {
 }
 
 /// Entry point of the RMoods server.
-/// Validates the environment, initializes the server and runs it.
+/// Sets up and validates the environment, initializes the server and runs it.
 #[tokio::main]
 async fn main() {
     std::env::set_var("RUST_LOG", "debug");
     std::env::set_var("RUST_BACKTRACE", "0");
     env_logger::init();
 
-    if dotenvy::dotenv().is_err() {
-        warn!(".env not found. Environment variables will have to be defined outside of .env");
-    }
+    setup_environment();
 
     if !verify_environment() {
         error!("Invalid environment, aborting.");

backend/src/startup.rs

@@ -28,6 +28,31 @@ pub fn verify_environment() -> bool {
     is_ok
 }
 
+/// Sets up the environment for the application.
+/// If we're in debug mode, we load the .env file.
+/// Otherwise, we expect all environment variables to be defined.
+pub fn setup_environment() {
+    #[cfg(debug_assertions)]
+    {
+        log::warn!("Running in debug mode.");
+        if dotenvy::dotenv().is_err() {
+            log::warn!(
+                "Failed to load .env file. Environment variables will have to be defined outside"
+            );
+        }
+    }
+
+    #[cfg(not(debug_assertions))]
+    {
+        log::warn!("Running in production mode.");
+        if dotenvy::from_filename_override(".env.prod").is_err() {
+            log::warn!(
+            "Failed to load .env.prod file. Environment variables will have to be defined outside"
+        );
+        }
+    }
+}
+
 pub async fn shutdown_signal(cancellation_token: CancellationToken) {
     let ctrl_c = async {
         signal::ctrl_c()