cojson 0.6.0

Collaborative JSON (A high performance CRDT)
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
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
134
135
136
137
138
139
140
141
142
143
144

use std::{collections::{HashMap, HashSet}, rc::Rc};

use crate::{
    ops::{ObjID, Op, OpKind},
    view::{
        jmbl_view::{JMBLViewRef, TranslatorRef},
        value::Value,
    }, io::SrcID,
};

use super::map_translator::MapTranslator;

#[derive(Clone)]
pub struct MapView {
    pub(crate) obj_id: ObjID,
    ctx: JMBLViewRef,
}

impl MapView {
    pub(crate) fn new(obj_id: ObjID, ctx: JMBLViewRef) -> MapView {
        MapView { obj_id, ctx }
    }

    fn translator_state(&self) -> Rc<MapTranslator> {
        match self
            .ctx
            .get_mut()
            .current_translator_for(&self.obj_id)
            .expect("Should have translator for map view")
        {
            TranslatorRef::Map(map_translator) => map_translator,
            _ => panic!("Expected Map Translator"),
        }
    }

    pub fn val(&self) -> HashMap<String, Value> {
        self.translator_state()
            .iter_entries()
            .map(|(key, val)| (key, self.ctx.litl_to_value(val)))
            .collect()
    }

    pub fn insert<K: Into<String>, V: Into<Value>>(&mut self, key: K, val: V) {
        let key_val = key.into();

        if let Some(last_op) = self.translator_state().last_op_for_key(&key_val) {
            // TODO(optimization): directly apply ops to correct object
            self.ctx.get_mut().apply_edit_op(
                self.obj_id,
                last_op.id,
                OpKind::MapSet,
                Some(litl::Val::array(vec![litl::Val::string(key_val), val.into().to_litl_or_ref()])),
            );
        } else {
            let create_op_id = self
                .translator_state()
                .create
                .clone()
                .expect("Expected create op on insert")
                .id;
            // TODO(optimization): directly apply ops to correct object
            self.ctx.get_mut().apply_edit_op(
                self.obj_id,
                create_op_id,
                OpKind::MapSet,
                Some(litl::Val::array(vec![litl::Val::string(key_val), val.into().to_litl_or_ref()])),
            );
        }
    }

    pub fn delete<I: Into<String>>(&mut self, key: I) {
        let key_val = key.into();
        if let Some(last_op) = self.translator_state().last_op_for_key(&key_val) {
            // TODO(optimization): directly apply ops to correct object
            self.ctx.get_mut().apply_edit_op(
                self.obj_id,
                last_op.id,
                OpKind::MapSet,
                Some(litl::Val::array(vec![key_val.into(), litl::Value::Null])),
            );
        }
        // else no-op
    }

    pub fn get<I: Into<String>>(&self, key: I) -> Value {
        self.apparent_value_for_key(key.into())
    }

    fn apparent_value_for_key(&self, key: String) -> Value {
        match self.translator_state().last_op_for_key_not_undone(&key) {
            Some(Op {
                kind: OpKind::MapSet,
                val: entry,
                ..
            }) => self.ctx.litl_to_value(entry.unwrap()[1].clone()),
            None => Value::plain(litl::Val::null()),
            Some(_other_op) => unreachable!("Only map ops expected"),
        }
    }

    pub fn val_to_litl(&self) -> litl::Val {
        litl::Val::object(
            self.val()
                .into_iter()
                .map(|(key, val)| (key, val.val_to_litl())),
        )
    }

    pub fn entries(&self) -> Vec<(String, litl::Val)> {
        self.translator_state().iter_entries().collect()
    }

    pub fn affecting_logs_for_key(&self, key: &str) -> HashSet<SrcID> {
        (*self.translator_state()).map.ops_for_key.get(key).map(|ops|
            ops.iter().map(|op| op.id.0).collect()
        ).unwrap_or_default()
    }

    pub fn last_op_for_key_not_undone(&self, key: &str) -> Option<Op> {
        self.translator_state().last_op_for_key_not_undone(key)
    }
}

impl std::fmt::Debug for MapView {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("MapView")
            .field("value", &self.val())
            .finish()
    }
}

impl std::cmp::PartialEq for MapView {
    fn eq(&self, other: &Self) -> bool {
        self.translator_state().map == other.translator_state().map
    }
}

impl std::cmp::Eq for MapView {}

impl std::hash::Hash for MapView {
    fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
        self.translator_state().map.hash(state);
    }
}