ousia 2.0.0

Postgres ORM with native double-entry ledger, graph relations, and atomic money operations for Rust
Documentation 
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

use std::borrow::Cow;

use crate::{Object, Union, edge::Edge, error::Error};
use chrono::{DateTime, Utc};
use serde::{Deserialize, Serialize};
use uuid::Uuid;

#[derive(Debug, Serialize, Deserialize)]
pub struct ObjectRecord {
    pub id: Uuid,
    pub type_name: Cow<'static, str>,
    pub owner: Uuid,
    /// MessagePack-encoded object payload (all fields, including private ones).
    pub data: Vec<u8>,
    /// JSONB-encoded index metadata — stays as serde_json::Value for GIN indexing.
    pub index_meta: serde_json::Value,
    pub created_at: DateTime<Utc>,
    pub updated_at: DateTime<Utc>,
}

impl ObjectRecord {
    pub fn to_object<T: Object>(self) -> Result<T, Error> {
        let mut val = rmp_serde::from_slice::<T>(&self.data)
            .map_err(|e| Error::Deserialize(e.to_string()))?;
        let meta = val.meta_mut();
        meta.id = self.id;
        meta.owner = self.owner;
        meta.created_at = self.created_at;
        meta.updated_at = self.updated_at;
        Ok(val)
    }

    pub fn from_object<'a, T: Object>(obj: &'a T) -> Self {
        let meta = obj.meta();
        Self {
            id: meta.id,
            type_name: Cow::Borrowed(obj.type_name()),
            owner: meta.owner,
            index_meta: serde_json::to_value(obj.index_meta())
                .expect("Failed to serialize index_meta"),
            data: obj.__serialize_internal(),
            created_at: meta.created_at,
            updated_at: meta.updated_at,
        }
    }
}

impl<A: Object, B: Object> Into<Union<A, B>> for ObjectRecord {
    fn into(self) -> Union<A, B> {
        match self.type_name.as_ref() {
            t if t == A::TYPE => ObjectRecord::to_object::<A>(self)
                .map(Union::First)
                .unwrap_or_else(|err| {
                    panic!("Error: {:?}", err);
                }),
            t if t == B::TYPE => ObjectRecord::to_object::<B>(self)
                .map(Union::Second)
                .unwrap_or_else(|err| {
                    panic!("Error: {:?}", err);
                }),
            _ => panic!("Invalid type name"),
        }
    }
}

#[derive(Debug, Serialize, Deserialize)]
pub struct EdgeRecord {
    pub type_name: Cow<'static, str>,
    pub from: Uuid,
    pub to: Uuid,
    /// MessagePack-encoded edge payload.
    pub data: Vec<u8>,
    /// JSONB-encoded index metadata.
    pub index_meta: serde_json::Value,
}

impl EdgeRecord {
    pub fn to_edge<E: Edge>(self) -> Result<E, Error> {
        let mut val = rmp_serde::from_slice::<E>(&self.data)
            .map_err(|e| Error::Deserialize(e.to_string()))?;
        let meta = val.meta_mut();
        meta.to = self.to;
        meta.from = self.from;
        Ok(val)
    }

    pub fn from_edge<'a, E: Edge>(edge: &'a E) -> Self {
        let meta = edge.meta();
        Self {
            to: meta.to,
            from: meta.from,
            type_name: Cow::Borrowed(edge.type_name()),
            data: rmp_serde::to_vec_named(edge).expect("Failed to msgpack serialize edge"),
            index_meta: serde_json::to_value(edge.index_meta())
                .expect("Failed to serialize index meta"),
        }
    }
}