Make byte size configurable

* Make byte size configurable
* Format code

Closes #76.

src/dsmr/reader.rs

@@ -108,14 +108,15 @@ pub fn connect_to_meter(
     consumer: &mut dyn super::TelegramConsumer,
 ) {
     log::info!(
-        "Connecting to {} using baud rate {} and parity bit {:#?}",
+        "Connecting to {} using baud rate {}, byte size {} and parity bit {:#?}",
         &serial_settings.port,
         &serial_settings.baud_rate,
+        &serial_settings.byte_size,
         &serial_settings.parity_bit
     );
 
     let mut port = serialport::new(&serial_settings.port, serial_settings.baud_rate)
-        .data_bits(serialport::DataBits::Seven)
+        .data_bits(to_databits(&serial_settings.byte_size))
         .flow_control(serialport::FlowControl::None)
         .parity(to_serial_port_parity_bit(&serial_settings.parity_bit))
         .stop_bits(serialport::StopBits::One)
@@ -134,6 +135,17 @@ fn to_serial_port_parity_bit(input: &ParityBitSetting) -> serialport::Parity {
     }
 }
 
+fn to_databits(input: &u8) -> serialport::DataBits {
+    match input {
+        0..=4 => serialport::DataBits::Eight,
+        5 => serialport::DataBits::Five,
+        6 => serialport::DataBits::Six,
+        7 => serialport::DataBits::Seven,
+        8 => serialport::DataBits::Eight,
+        9..=u8::MAX => serialport::DataBits::Eight,
+    }
+}
+
 #[cfg(test)]
 mod tests {
     #[allow(unused_imports)]

src/dsmr/settings.rs

@@ -12,6 +12,7 @@ pub struct SerialSettings {
     pub port: String,
     pub baud_rate: u32,
     pub parity_bit: ParityBitSetting,
+    pub byte_size: u8,
 }
 
 pub struct Host {
@@ -46,11 +47,16 @@ fn read_serial_settings(settings: &HashMap<String, String>) -> Result<SerialSett
         },
         None => ParityBitSetting::None,
     };
+    let byte_size = match settings.get("serial_bytesize") {
+        Some(value) => value.parse::<u8>().unwrap(),
+        None => 8,
+    };
 
     Ok(SerialSettings {
         port: serial_port.to_string(),
         baud_rate: serial_baudrate,
         parity_bit,
+        byte_size,
     })
 }
 
@@ -178,6 +184,20 @@ mod tests {
         assert_eq!(value.parity_bit, ParityBitSetting::Even);
     }
 
+    #[test]
+    fn read_serial_settings_with_byte_size_seven() {
+        let mut settings = HashMap::new();
+        settings.insert(String::from("serial_port"), String::from("/dev/ttyUSB0"));
+        settings.insert(String::from("serial_baudrate"), String::from("9600"));
+        settings.insert(String::from("serial_bytesize"), String::from("7"));
+
+        let result = read_serial_settings(&settings);
+
+        assert_eq!(result.is_ok(), true);
+        let value = result.unwrap();
+        assert_eq!(value.byte_size, 7);
+    }
+
     #[test]
     fn host_settings_single_pair() {
         let mut settings = HashMap::new();