Struct SqlInterfaceVentilationSetVals

pub struct SqlInterfaceVentilationSetVals {
    pub conn: PooledConn,
    update_time: Option<Instant>,
    update_duration: Duration,
}

Fields

conn: PooledConn

Connection to the database

update_time: Option<Instant>

recording of time when the database has been polled for the last time

update_duration: Duration

target update duration

Implementations

impl SqlInterfaceVentilationSetVals

pub fn new( conn: PooledConn, config: &VentilationConfig, ) -> Result<Self, SqlInterfaceError>

Creates a new SqlInterfaceVentilationSetVals instance.

This constructor initializes the SQL interface for ventilation set values. It performs several pre-flight checks to ensure data integrity, such as verifying that the ventilationsetvals table contains no NULL values and has at most one row.

Arguments

• conn - An active, pooled database connection.
• config - A reference to the ventilation configuration to determine the update interval.

Returns

A Result containing a new SqlInterfaceVentilationSetVals instance on success.

Errors

This function will return an error if:

• Any of the initial database queries to get table counts fail (DatabaseCheckVentilationSetValsFailure).
• Any of the retrieved counts are negative, indicating a database issue (DatabaseVentilationSetValTableNegativeValue).
• The ventilationsetvals table contains entries with NULL values (DatabaseVentilationSetValTableContainsNull).
• The ventilationsetvals table contains more than one row (DatabaseVentilationSetValTableContainsTooManyRows).

pub fn get_ventilation_set_values( &mut self, ) -> Result<Option<VentilationSetVals>, SqlInterfaceError>

Retrieves the ventilation set point values (switch-on and switch-off temperatures) from the database.

This function queries the database for the configured ventilation thresholds. It expects either no entries (if values haven’t been set yet) or exactly one entry.

It performs the following checks:

1. **Query Execution: ** Attempts to fetch ventilation set values from the database using SQL_QUERY_READ_VENTILATION_STATS.
2. **Empty Result: ** If the query returns no entries, it indicates that the set points have not yet been configured in the database, and Ok(None) is returned.
3. **Multiple Results: ** If the query returns more than one entry, it signifies a data inconsistency, and an Err is returned, as only a single set of ventilation values is expected.
4. **Consistency Check: ** Validates that the ventilation_switch_on_temperature is not greater than the ventilation_switch_off_temperature. If this crucial control logic consistency is violated, an Err is returned.

Returns

• Ok(Some(VentilationSetVals)): If a single, consistent set of ventilation set values is successfully retrieved.
• Ok(None): If the database query returns no entries, indicating that values have not yet been configured.
• Err(SqlInterfaceError::VentilationSetValsReadError): If there’s an error during database interaction, if multiple entries are found, or if the retrieved values fail the consistency check (e.g., switch_on_temperature is higher than switch_off_temperature).

Errors

This function returns an SqlInterfaceError::VentilationSetValsReadError in the following cases:

• The underlying database query fails.
• More than one VentilationSetVals entry is found in the database.
• The ventilation_switch_on_temperature is found to be greater than the ventilation_switch_off_temperature, which is a critical configuration inconsistency.

Trait Implementations

impl Debug for SqlInterfaceVentilationSetVals

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl ThermalSetValueUpdaterTrait for SqlInterfaceVentilationSetVals

fn update_set_value( &mut self, ventilation_switch_off_temperature: &mut f32, ventilation_switch_on_temperature: &mut f32, ) -> Result<(), SqlInterfaceError>

Periodically updates ventilation set point values from the database.

This method checks if a configured interval (update_duration) has passed since the last database check. If it has, it queries the database for the latest VentilationSetVals and updates the provided mutable references. If no values are found in the database, the existing values are kept unchanged.

Arguments

• ventilation_switch_off_temperature - A mutable reference to the current switch-off temperature.
• ventilation_switch_on_temperature - A mutable reference to the current switch-on temperature.

Returns

An empty Result (Ok(())) on success. Success includes cases where the update was skipped due to the time interval or when no new values were found in the database.

Errors

Returns SqlInterfaceError::VentilationSetValsUpdateFailure if the underlying call to get_ventilation_set_values fails. This can happen due to a database connection issue, data inconsistency (e.g., multiple rows), or invalid set values.