1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113

//! Diesel models of metrics sqlite storage
use crate::schema::{metric_keys, metrics};
use crate::{MetricsError, Result};
use ::metrics::Unit;
use diesel::prelude::*;
use std::borrow::Cow;

/// A new metric measurement for storing into sqlite database
#[derive(Insertable, Debug)]
#[table_name = "metrics"]
pub struct NewMetric {
    /// Timestamp of sample
    pub timestamp: f64,
    /// Key/name of sample
    pub metric_key_id: i64,
    /// Value of sample
    pub value: f64,
}

/// New metric key entry
#[derive(Insertable, Debug)]
#[table_name = "metric_keys"]
pub struct NewMetricKey<'a> {
    /// Actual key
    pub key: Cow<'a, str>,
    /// Unit if any
    pub unit: Cow<'a, str>,
    /// Description of metric key if any
    pub description: Cow<'a, str>,
}

/// Metric key
#[derive(Queryable, Debug, Identifiable)]
#[cfg_attr(feature = "serde", derive(serde::Serialize))]
pub struct MetricKey<'a> {
    /// primary key of metric key
    pub id: i64,
    /// Actual key
    pub key: Cow<'a, str>,
    /// Unit if any
    pub unit: Cow<'a, str>,
    /// Description of metric key if any
    pub description: Cow<'a, str>,
}
impl<'a> MetricKey<'a> {
    pub(crate) fn create_or_update(
        key_name: &str,
        unit: Option<Unit>,
        description: Option<&'a str>,
        db: &SqliteConnection,
    ) -> Result<MetricKey<'a>> {
        let key = Self::key_by_name(key_name, db)?;
        let unit_value = unit
            .map(|u| Cow::Owned(u.as_str().to_string()))
            .unwrap_or(Cow::Borrowed(""));
        let description = description.map(Cow::Borrowed).unwrap_or(Cow::Borrowed(""));
        Self::update(key.id, unit_value, description, db)?;
        Ok(key)
    }
    fn update(
        id_value: i64,
        unit_value: Cow<'a, str>,
        description_value: Cow<'a, str>,
        db: &SqliteConnection,
    ) -> Result<()> {
        use crate::schema::metric_keys::dsl::*;
        diesel::update(metric_keys.filter(id.eq(id_value)))
            .set((unit.eq(unit_value), description.eq(description_value)))
            .execute(db)?;
        Ok(())
    }
    pub(crate) fn key_by_name(key_name: &str, db: &SqliteConnection) -> Result<MetricKey<'a>> {
        use crate::schema::metric_keys::dsl::metric_keys;
        match Self::key_by_name_inner(key_name, db) {
            Ok(key) => Ok(key),
            Err(MetricsError::KeyNotFound(_)) => {
                // not stored yet so create an entry
                let new_key = NewMetricKey {
                    key: Cow::Borrowed(key_name),
                    unit: Cow::Borrowed(""),
                    description: Cow::Borrowed(""),
                };
                new_key.insert_into(metric_keys).execute(db)?;
                // fetch it back out to get the ID
                Self::key_by_name_inner(key_name, db)
            }
            Err(e) => Err(e),
        }
    }
    fn key_by_name_inner(key_name: &str, db: &SqliteConnection) -> Result<MetricKey<'a>> {
        use crate::schema::metric_keys::dsl::*;
        let query = metric_keys.filter(key.eq(key_name));
        let keys = query.load::<MetricKey>(db)?;
        keys.into_iter()
            .next()
            .ok_or_else(|| MetricsError::KeyNotFound(key_name.to_string()))
    }
}

/// Metric model for existing entries in sqlite database
#[derive(Queryable, Debug, Identifiable, Associations)]
#[belongs_to(MetricKey<'_>)]
#[cfg_attr(feature = "serde", derive(serde::Serialize))]
pub struct Metric {
    /// Unique ID of sample
    pub id: i64,
    /// Timestamp of sample
    pub timestamp: f64,
    /// Key/name of sample
    pub metric_key_id: i64,
    /// Value of sample
    pub value: f64,
}