Backend Logging

The backend uses env_logger together with log as a logging framework.

env_logger allows to configure logging via the environment variable RUST_LOG.

Changing the Logging Level

To change the log level you can do one of the following:

Run the backend with e.g. RUST_LOG='backend=debug,actix_web=info' cargo run to change the log level of our code to debug
Change the variable RUST_LOG in the .env file

Log Messages

Use detailed logging messages for easy troubleshooting. It must be clear what should have happened and what actually happened.
Include relevant context, parameters, error codes etc.
Log only if actually needed. Exceptions: all calls of endpoints and SQL queries should be completely logged (level: debug).
Always use the lowest applicable logging level.

Log Levels

Available logging levels are:

error
Use for events disrupting normal operations.
warn
Apply for potentially harmful situations or undesirable yet operational states.
info
Use to monitor the essential flow of the application, capturing important operations like successful user authentications.
debug
Reserved for development or debugging; includes detailed updates, states of critical application points, or SQL queries.
trace
Use for granular logging, such as step-by-step function execution, to aid in complex issue diagnosis.

How to add Logging

To log you can simply call the macros in the log crate.

For example to log using the debug level:

log::debug!("This is my variable: {}", some_variable);

As you can see, it can be used in the same way as for example println!().

Log SQL queries

SQL queries can be converted to something that can be logged using debug_query.

let query = diesel::delete(seeds::table.find(id));
debug!("{}", debug_query::<Pg, _>(&query));
query.execute(conn).await

PLSQL Logging using RAISE NOTICE And RAISE EXCEPTION

For debugging or info purposes RAISE NOTICE and RAISE EXCEPTION can be used in PLSQL. To be able to see the output from those on the server activate the logging with the following commands:

ALTER SYSTEM SET client_min_messages TO notice;
ALTER SYSTEM SET log_min_messages TO notice;
SELECT pg_reload_conf();

For debugging with the psql db-client built into the terminal this is not needed. This client can be started with the following command using terminal:

PGPASSWORD=permaplant psql -h localhost -p 5432 -U permaplant permaplant

After starting the db including its PLSQL-functions can be accessed.

PermaplanT