HomeServer/src/db.rs

use std::path::Path;

use anyhow::Result;
use rusqlite::{Connection, ToSql};

pub struct DataBase {
    sql: Connection,
}

impl DataBase {
    pub async fn new(path: impl AsRef<Path>) -> Result<Self> {
        let me = Self {
            sql: Connection::open(path)?,
        };

        me.generate_tables()?;

        Ok(me)
    }

    fn generate_tables(&self) -> Result<()> {
        self.sql.execute(
            "CREATE TABLE IF NOT EXISTS data (
                id      INTEGER PRIMARY KEY,
                device  TEXT NOT NULL,
                time    BIGINT NOT NULL,
                watts   REAL NOT NULL
            )",
            [],
        )?;

        Ok(())
    }

    pub fn write(&self, device_name: &str, time: u64, watts: f32) -> Result<()> {
        let params: &[&dyn ToSql] = &[&device_name, &time, &watts];

        self.sql.execute(
            "INSERT INTO data (device, time, watts)
                VALUES (?1, ?2, ?3)",
            params,
        )?;

        Ok(())
    }

    pub fn read(&self, device: &str) -> Result<Vec<(u64, f32)>> {
        self.sql
            .prepare(&format!(
                // "
                //     SELECT time, watts
                //     FROM  data
                //     WHERE device={device}
                // "
                "
                    SELECT time, watts
                    FROM  data
                "
            ))?
            .query_map([], |row| Ok((row.get(0)?, row.get(1)?)))?
            .map(|row| {
                let (time, watts) = row?;

                Ok((time, watts))
            })
            .collect()
    }
}

#[cfg(test)]
mod test {
    use std::fs;

    use anyhow::Result;

    use super::DataBase;

    #[tokio::test]
    async fn test_connection() -> Result<()> {
        DataBase::new("connection_test.db").await?;

        fs::remove_file("connection_test.db")?;

        Ok(())
    }

    #[tokio::test]
    async fn test_write() -> Result<()> {
        let db = DataBase::new("write_test.db").await?;

        db.write("test", 0, 5.5)?;

        fs::remove_file("write_test.db")?;

        Ok(())
    }
}