How to set up a database connection from environment in Rocket? - database

Question

I have following working database connection setup for my Rocket app:
main.rs:
#[database("my_db")]
pub struct DbConn(diesel::PgConnection);
Rocket.toml:
[global.databases]
my_db = { url = "postgres://user:pass#localhost/my_db" }
I would like to set username, password and a database name from the environment. Expected it to be something like ROCKET_MY_DB=postgres://user:pass#localhost/my_db, but it didn't work. Was unable find relevant database example for Rocket.

Answer 1

After a lot of experiments (as there is no specific instructions for the database and I expected something that looked more like a standard approach: ENV_PARAM=conn_string, i.e. in Diesel) I finally figured out that I need to place a complex object into the environment.
The solution is this ugly string:
ROCKET_DATABASES={my_db={url="postgres://user:pass#localhost/my_db"}}

Answer 2

I would like to set username, password and a database name from the environment. Didn't find relevant example for Rocket.
Front page of the doc
Rocket and Rocket libraries are configured via the Rocket.toml file and/or ROCKET_{PARAM} environment variables. For more information on how to configure Rocket, see the configuration section of the guide as well as the config module documentation.
Example just follow link:
All configuration parameters, including extras, can be overridden through environment variables. To override the configuration parameter {param}, use an environment variable named ROCKET_{PARAM}. For instance, to override the "port" configuration parameter, you can run your application with:
ROCKET_PORT=3721 ./your_application
🔧 Configured for development.
=> ...
=> port: 3721 ```