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
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133

use std::collections::BTreeMap;
use std::convert::TryFrom;
use std::fmt::Debug;
use value::Value;
use error::DaoError;
use serde::ser::{Serialize, Serializer};

#[derive(Debug, PartialEq)]
pub struct Dao<'a>(pub BTreeMap<&'a str, Value>);

impl<'a> Dao<'a> {
    pub fn new() -> Self {
        Dao(BTreeMap::new())
    }

    pub fn insert<V>(&mut self, s: &'a str, v: V)
    where
        V: Into<Value>,
    {
        self.0.insert(s, v.into());
    }

    pub fn insert_value(&mut self, s: &'a str, value: Value) {
        self.0.insert(s, value);
    }

    pub fn get<T>(&'a self, s: &str) -> Result<T, DaoError<T>>
    where
        T: TryFrom<&'a Value>,
        T::Error: Debug,
    {
        let value: Option<&'a Value> = self.0.get(s);
        match value {
            Some(v) => TryFrom::try_from(v).map_err(|e| DaoError::ConvertError(e)),
            None => Err(DaoError::NoSuchValueError(s.into())),
        }
    }
    
    pub fn get_value(&self, s: &str) -> Option<&Value> {
        self.0.get(s)
    }

    pub fn remove(&mut self, s: &str) -> Option<Value> {
        self.0.remove(s)
    }
}

impl<'a> Serialize for Dao<'a> {
    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: Serializer,
    {
        self.0.serialize(serializer)
    }
}

pub trait FromDao {
    /// convert dao to an instance of the corresponding struct of the model
    /// taking into considerating the renamed columns
    fn from_dao(dao: &Dao) -> Self;
}

pub trait ToDao {
    /// convert from an instance of the struct to a dao representation
    /// to be saved into the database
    fn to_dao(&self) -> Dao;
}

#[cfg(test)]
mod tests {
    use super::*;
    use uuid::Uuid;
    use serde_json;

    #[test]
    fn insert_double() {
        let mut dao = Dao::new();
        dao.insert("life", 42.0f64);
        let life: Result<f64, DaoError<f64>> = dao.get("life");
        assert_eq!(life.unwrap(), 42.0f64);
    }

    #[test]
    fn insert_float() {
        let mut dao = Dao::new();
        dao.insert("life", 42.0f32);
        let life: Result<f64, DaoError<f64>> = dao.get("life");
        assert_eq!(life.unwrap(), 42.0f64);
    }

    #[test]
    fn uuid() {
        let mut dao = Dao::new();
        let uuid = Uuid::new_v4();
        dao.insert("user_id", uuid);
    }

    #[test]
    fn serialize_json() {
        let mut dao = Dao::new();
        dao.insert("life", 42);
        dao.insert("lemons", "lemonade");
        let json = serde_json::to_string(&dao).unwrap();
        let expected = r#"{"lemons":{"Text":"lemonade"},"life":{"Int":42}}"#;
        assert_eq!(json, expected);
    }

    #[test]
    fn test_get_opt() {
        let mut dao = Dao::new();
        dao.insert("life", 42);
        let life: Result<Option<i32>, _> = dao.get("life");
        assert!(life.is_ok());
        let life = life.unwrap();
        assert!(life.is_some());
        assert_eq!(life.unwrap(), 42);
    }

    #[test]
    fn referenced() {
        let mut dao = Dao::new();
        let v = 42;
        let s = "lemonade";
        dao.insert("life", &v);
        dao.insert("lemons", &s);
        let life: Result<Option<i32>, _> = dao.get("life");
        assert!(life.is_ok());
        let life = life.unwrap();
        assert!(life.is_some());
        assert_eq!(life.unwrap(), 42);
    }

}