es_entity/
nested.rs

1//! Handle operations for nested entities.
2
3use crate::{operation::AtomicOperation, traits::*};
4
5use std::collections::HashMap;
6
7pub struct Nested<T: EsEntity> {
8    entities: HashMap<<<T as EsEntity>::Event as EsEvent>::EntityId, T>,
9    new_entities: Vec<<T as EsEntity>::New>,
10}
11
12impl<T: EsEntity> Default for Nested<T> {
13    fn default() -> Self {
14        Self {
15            entities: HashMap::new(),
16            new_entities: Vec::new(),
17        }
18    }
19}
20
21impl<T: EsEntity> Nested<T> {
22    pub fn add_new(&mut self, new: <T as EsEntity>::New) -> &<T as EsEntity>::New {
23        let len = self.new_entities.len();
24        self.new_entities.push(new);
25        &self.new_entities[len]
26    }
27
28    pub fn get_persisted(&self, id: &<<T as EsEntity>::Event as EsEvent>::EntityId) -> Option<&T> {
29        self.entities.get(id)
30    }
31
32    pub fn get_persisted_mut(
33        &mut self,
34        id: &<<T as EsEntity>::Event as EsEvent>::EntityId,
35    ) -> Option<&mut T> {
36        self.entities.get_mut(id)
37    }
38
39    pub fn find_persisted<P>(&self, predicate: P) -> Option<&T>
40    where
41        P: FnMut(&&T) -> bool,
42    {
43        self.entities.values().find(predicate)
44    }
45
46    pub fn find_persisted_mut<P>(&mut self, predicate: P) -> Option<&mut T>
47    where
48        P: FnMut(&&mut T) -> bool,
49    {
50        self.entities.values_mut().find(predicate)
51    }
52
53    pub fn len_persisted(&self) -> usize {
54        self.entities.len()
55    }
56
57    pub fn iter_persisted_mut(&mut self) -> impl Iterator<Item = &mut T> {
58        self.entities.values_mut()
59    }
60
61    pub fn new_entities_mut(&mut self) -> &mut Vec<<T as EsEntity>::New> {
62        &mut self.new_entities
63    }
64
65    pub fn load(&mut self, entities: impl IntoIterator<Item = T>) {
66        self.entities.extend(
67            entities
68                .into_iter()
69                .map(|entity| (entity.events().entity_id.clone(), entity)),
70        );
71    }
72}
73
74pub trait PopulateNested<ID>: EsRepo {
75    fn populate_in_op<OP, P>(
76        op: &mut OP,
77        lookup: std::collections::HashMap<ID, &mut P>,
78    ) -> impl Future<Output = Result<(), <Self as EsRepo>::Err>> + Send
79    where
80        OP: AtomicOperation,
81        P: Parent<<Self as EsRepo>::Entity>;
82}
83
84/// Trait that entities implement for every field marked `#[es_entity(nested)]`
85/// Will be auto-implemented when `#[derive(EsEntity)] is used.
86pub trait Parent<T: EsEntity>: Send {
87    /// Access new child entities to persist them.
88    fn new_children_mut(&mut self) -> &mut Vec<<T as EsEntity>::New>;
89    /// Access existing children to update them incase they were mutated.
90    fn iter_persisted_children_mut<'a>(&'a mut self) -> impl Iterator<Item = &'a mut T>
91    where
92        T: 'a;
93    /// Inject hydrated children while loading the parent.
94    fn inject_children(&mut self, entities: impl IntoIterator<Item = T>);
95}