feat!: [#938] add mandatory config options

Some configuration options are mandatory. The tracker will panic if the user doesn't provide an explicit value for them from one of the configuration sources: TOML or ENV VARS.

The mandatory options are:

```toml
[metadata]
schema_version = "2.0.0"

[logging]
threshold = "info"

[core]
private = false
listed = false
```

packages/configuration/src/lib.rs

@@ -303,6 +303,9 @@ pub enum Error {
 
  #[error("Unsupported configuration version: {version}")]
  UnsupportedVersion { version: Version },
+
+ #[error("Missing mandatory configuration option. Option path: {path}")]
+ MissingMandatoryOption { path: String },
 }
 
 impl From<figment::Error> for Error {

packages/configuration/src/v2_0_0/mod.rs

@@ -313,27 +313,33 @@ impl Configuration {
  }
 
  /// Loads the configuration from the `Info` struct. The whole
- /// configuration in toml format is included in the `info.tracker_toml` string.
+ /// configuration in toml format is included in the `info.tracker_toml`
+ /// string.
  ///
- /// Optionally will override the admin api token.
+ /// Configuration provided via env var has priority over config file path.
  ///
  /// # Errors
  ///
  /// Will return `Err` if the environment variable does not exist or has a bad configuration.
  pub fn load(info: &Info) -> Result<Configuration, Error> {
+ // Load configuration provided by the user, prioritizing env vars
  let figment = if let Some(config_toml) = &info.config_toml {
- // Config in env var has priority over config file path
- Figment::from(Serialized::defaults(Configuration::default()))
- .merge(Toml::string(config_toml))
- .merge(Env::prefixed(CONFIG_OVERRIDE_PREFIX).split(CONFIG_OVERRIDE_SEPARATOR))
+ Figment::from(Toml::string(config_toml)).merge(Env::prefixed(CONFIG_OVERRIDE_PREFIX).split(CONFIG_OVERRIDE_SEPARATOR))
  } else {
- Figment::from(Serialized::defaults(Configuration::default()))
- .merge(Toml::file(&info.config_toml_path))
+ Figment::from(Toml::file(&info.config_toml_path))
  .merge(Env::prefixed(CONFIG_OVERRIDE_PREFIX).split(CONFIG_OVERRIDE_SEPARATOR))
  };
 
+ // Make sure user has provided the mandatory options.
+ Self::check_mandatory_options(&figment)?;
+
+ // Fill missing options with default values.
+ let figment = figment.join(Serialized::defaults(Configuration::default()));
+
+ // Build final configuration.
  let config: Configuration = figment.extract()?;
 
+ // Make sure the provided schema version matches this version.
  if config.metadata.schema_version != Version::new(VERSION_2_0_0) {
  return Err(Error::UnsupportedVersion {
  version: config.metadata.schema_version,
@@ -343,6 +349,28 @@ impl Configuration {
  Ok(config)
  }
 
+ /// Some configuration options are mandatory. The tracker will panic if
+ /// the user doesn't provide an explicit value for them from one of the
+ /// configuration sources: TOML or ENV VARS.
+ ///
+ /// # Errors
+ ///
+ /// Will return an error if a mandatory configuration option is only
+ /// obtained by default value (code), meaning the user hasn't overridden it.
+ fn check_mandatory_options(figment: &Figment) -> Result<(), Error> {
+ let mandatory_options = ["metadata.schema_version", "logging.threshold", "core.private", "core.listed"];
+
+ for mandatory_option in mandatory_options {
+ figment
+ .find_value(mandatory_option)
+ .map_err(|_err| Error::MissingMandatoryOption {
+ path: mandatory_option.to_owned(),
+ })?;
+ }
+
+ Ok(())
+ }
+
  /// Saves the configuration to the configuration file.
  ///
  /// # Errors
@@ -496,14 +524,25 @@ mod tests {
  }
 
  #[test]
- fn configuration_should_use_the_default_values_when_an_empty_configuration_is_provided_by_the_user() {
+ fn configuration_should_use_the_default_values_when_only_the_mandatory_options_are_provided_by_the_user_via_toml_file() {
  figment::Jail::expect_with(|jail| {
- jail.create_file("tracker.toml", "")?;
+ jail.create_file(
+ "tracker.toml",
+ r#"
+ [metadata]
+ schema_version = "2.0.0"
+
+ [logging]
+ threshold = "info"
 
- let empty_configuration = String::new();
+ [core]
+ listed = false
+ private = false
+ "#,
+ )?;
 
  let info = Info {
- config_toml: Some(empty_configuration),
+ config_toml: None,
  config_toml_path: "tracker.toml".to_string(),
  };
 
@@ -515,10 +554,49 @@ mod tests {
  });
  }
 
+ #[test]
+ fn configuration_should_use_the_default_values_when_only_the_mandatory_options_are_provided_by_the_user_via_toml_content() {
+ figment::Jail::expect_with(|_jail| {
+ let config_toml = r#"
+ [metadata]
+ schema_version = "2.0.0"
+
+ [logging]
+ threshold = "info"
+
+ [core]
+ listed = false
+ private = false
+ "#
+ .to_string();
+
+ let info = Info {
+ config_toml: Some(config_toml),
+ config_toml_path: String::new(),
+ };
+
+ let configuration = Configuration::load(&info).expect("Could not load configuration from file");
+
+ assert_eq!(configuration, Configuration::default());
+
+ Ok(())
+ });
+ }
+
  #[test]
  fn default_configuration_could_be_overwritten_from_a_single_env_var_with_toml_contents() {
  figment::Jail::expect_with(|_jail| {
  let config_toml = r#"
+ [metadata]
+ schema_version = "2.0.0"
+
+ [logging]
+ threshold = "info"
+
+ [core]
+ listed = false
+ private = false
+
  [core.database]
  path = "OVERWRITTEN DEFAULT DB PATH"
  "#
@@ -543,6 +621,16 @@ mod tests {
  jail.create_file(
  "tracker.toml",
  r#"
+ [metadata]
+ schema_version = "2.0.0"
+
+ [logging]
+ threshold = "info"
+
+ [core]
+ listed = false
+ private = false
+
  [core.database]
  path = "OVERWRITTEN DEFAULT DB PATH"
  "#,

share/default/config/tracker.container.mysql.toml

@@ -3,6 +3,13 @@ app = "torrust-tracker"
 purpose = "configuration"
 schema_version = "2.0.0"
 
+[logging]
+threshold = "info"
+
+[core]
+listed = false
+private = false
+
 [core.database]
 driver = "mysql"
 path = "mysql://db_user:db_user_secret_password@mysql:3306/torrust_tracker"

share/default/config/tracker.container.sqlite3.toml

@@ -3,6 +3,13 @@ app = "torrust-tracker"
 purpose = "configuration"
 schema_version = "2.0.0"
 
+[logging]
+threshold = "info"
+
+[core]
+listed = false
+private = false
+
 [core.database]
 path = "/var/lib/torrust/tracker/database/sqlite3.db"
 

share/default/config/tracker.development.sqlite3.toml

@@ -3,6 +3,13 @@ app = "torrust-tracker"
 purpose = "configuration"
 schema_version = "2.0.0"
 
+[logging]
+threshold = "info"
+
+[core]
+listed = false
+private = false
+
 [[udp_trackers]]
 bind_address = "0.0.0.0:6969"
 

share/default/config/tracker.e2e.container.sqlite3.toml

@@ -3,6 +3,13 @@ app = "torrust-tracker"
 purpose = "configuration"
 schema_version = "2.0.0"
 
+[logging]
+threshold = "info"
+
+[core]
+listed = false
+private = false
+
 [core.database]
 path = "/var/lib/torrust/tracker/database/sqlite3.db"
 

share/default/config/tracker.udp.benchmarking.toml

@@ -7,6 +7,8 @@ schema_version = "2.0.0"
 threshold = "error"
 
 [core]
+listed = false
+private = false
 remove_peerless_torrents = false
 tracker_usage_statistics = false