react-rust-postgres: add readmes

Signed-off-by: Jérémie Drouet <jeremie.drouet@gmail.com>

README.md

@@ -58,6 +58,8 @@ docker-compose down
   application with a Spring backend and a MySQL database
 - [`React / Express / MySQL`](react-express-mysql) -- sample React
   application with a NodeJS backend and a MySQL database
+- [`React / Rust / PostgreSQL`](react-rust-postgres) -- sample React
+  application with a Rust backend and a Postgres database
 - [`Spring / PostgreSQL`](spring-postgres) -- sample Java application
   with Spring framework and a Postgres database
 

react-rust-postgres/backend/readme.md

@@ -0,0 +1,4 @@
+# Backend
+
+This backend is made with Rust using [Rocket](https://rocket.rs/) as a web server and [Diesel](https://diesel.rs/) as an ORM.
+

react-rust-postgres/readme.md

@@ -0,0 +1,76 @@
+## Compose sample application
+
+### React application with a Rust backend and a Postgresql database
+
+Project structure:
+```
+.
+├── backend
+│   ├── Dockerfile
+│   ...
+├── docker-compose.yaml
+├── frontend
+│   ├── ...
+│   └── Dockerfile
+└── README.md
+```
+
+[_docker-compose.yaml_](docker-compose.yaml)
+```
+services:
+  backend:
+    build: backend
+    ...
+  db:
+    image: postgres:12-alpine
+    ...
+  frontend:
+    build: frontend
+    ports:
+    - 3000:3000
+    ...
+```
+The compose file defines an application with three services `frontend`, `backend` and `db`.
+When deploying the application, docker-compose maps port 3000 of the frontend service container to port 3000 of the host as specified in the file.
+Make sure port 3000 on the host is not already being in use.
+
+## Deploy with docker-compose
+
+```
+$ docker-compose up -d
+Creating network "react-rust-postgres_default" with the default driver
+Building backend
+...
+Successfully tagged react-rust-postgres_frontend:latest
+WARNING: Image for service frontend was built because it did not already exist. To rebuild this image you must use `docker-compose build` or `docker-compose up --build`.
+Creating react-rust-postgres_frontend_1 ... done
+Creating react-rust-postgres_db_1       ... done
+Creating react-rust-postgres_backend_1  ... done
+```
+
+## Expected result
+
+Listing containers must show three containers running and the port mapping as below:
+```
+$ docker ps
+CONTAINER ID        IMAGE                          COMMAND                  CREATED             STATUS              PORTS                    NAMES
+30b7d9dc4898        react-rust-postgres_backend    "cargo run --offline"    37 seconds ago      Up 35 seconds       8000/tcp                 react-rust-postgres_backend_1
+0bca0cb682b8        react-rust-postgres_frontend   "docker-entrypoint.s…"   42 seconds ago      Up 41 seconds       0.0.0.0:3000->3000/tcp   react-rust-postgres_frontend_1
+1611961bf3d1        postgres:12-alpine             "docker-entrypoint.s…"   42 seconds ago      Up 36 seconds       0.0.0.0:5432->5432/tcp   react-rust-postgres_db_1
+```
+
+After the application starts, navigate to `http://localhost:3000` in your web browser to get a colorful message.
+
+![page](./capture.png)
+
+Stop and remove the containers
+```
+$ docker-compose down
+Stopping react-rust-postgres_backend_1  ... done
+Stopping react-rust-postgres_frontend_1 ... done
+Stopping react-rust-postgres_db_1       ... done
+Removing react-rust-postgres_backend_1  ... done
+Removing react-rust-postgres_frontend_1 ... done
+Removing react-rust-postgres_db_1       ... done
+Removing network react-rust-postgres_default
+```