icydb_core/db/query/session/
delete.rs

1use crate::{
2    db::{
3        DbSession,
4        query::{
5            Query, QueryError,
6            expr::{FilterExpr, SortExpr},
7            plan::{ExecutablePlan, ExplainPlan},
8            predicate::Predicate,
9        },
10        response::Response,
11    },
12    traits::{CanisterKind, EntityKind, EntityValue, SingletonEntity},
13    types::{Id, Ref},
14};
15
16///
17/// SessionDeleteQuery
18///
19/// Session-bound delete query wrapper.
20/// This type owns *intent construction* and *execution routing only*.
21/// All result projection and cardinality handling lives on `Response<E>`.
22///
23
24pub struct SessionDeleteQuery<'a, C, E>
25where
26    C: CanisterKind,
27    E: EntityKind<Canister = C>,
28{
29    session: &'a DbSession<C>,
30    query: Query<E>,
31}
32
33impl<'a, C, E> SessionDeleteQuery<'a, C, E>
34where
35    C: CanisterKind,
36    E: EntityKind<Canister = C>,
37{
38    pub(crate) const fn new(session: &'a DbSession<C>, query: Query<E>) -> Self {
39        Self { session, query }
40    }
41
42    // ------------------------------------------------------------------
43    // Intent inspection
44    // ------------------------------------------------------------------
45
46    #[must_use]
47    pub const fn query(&self) -> &Query<E> {
48        &self.query
49    }
50
51    // ------------------------------------------------------------------
52    // Intent builders (pure)
53    // ------------------------------------------------------------------
54
55    /// Set the access path to a single entity identity.
56    #[must_use]
57    pub fn by_id(mut self, id: Id<E>) -> Self {
58        self.query = self.query.by_id(id.into_key());
59        self
60    }
61
62    /// Set the access path to multiple entity identities.
63    #[must_use]
64    pub fn by_ids<I>(mut self, ids: I) -> Self
65    where
66        I: IntoIterator<Item = Id<E>>,
67    {
68        self.query = self.query.by_ids(ids.into_iter().map(Id::into_key));
69        self
70    }
71
72    // ------------------------------------------------------------------
73    // Reference-based intent builders
74    // ------------------------------------------------------------------
75
76    /// Resolve a semantic entity reference.
77    #[must_use]
78    pub fn by_ref(mut self, r: Ref<E>) -> Self {
79        // Core is allowed to inspect / resolve refs
80        let key = r.into_storage_key(); // pub(crate)
81        self.query = self.query.by_id(key);
82        self
83    }
84
85    #[must_use]
86    pub fn by_refs<I>(mut self, refs: I) -> Self
87    where
88        I: IntoIterator<Item = Ref<E>>,
89    {
90        let keys = refs.into_iter().map(Ref::into_storage_key);
91        self.query = self.query.by_ids(keys);
92        self
93    }
94
95    // ------------------------------------------------------------------
96    // Query Refinement
97    // ------------------------------------------------------------------
98
99    #[must_use]
100    pub fn filter(mut self, predicate: Predicate) -> Self {
101        self.query = self.query.filter(predicate);
102        self
103    }
104
105    pub fn filter_expr(mut self, expr: FilterExpr) -> Result<Self, QueryError> {
106        self.query = self.query.filter_expr(expr)?;
107        Ok(self)
108    }
109
110    pub fn sort_expr(mut self, expr: SortExpr) -> Result<Self, QueryError> {
111        self.query = self.query.sort_expr(expr)?;
112        Ok(self)
113    }
114
115    #[must_use]
116    pub fn order_by(mut self, field: impl AsRef<str>) -> Self {
117        self.query = self.query.order_by(field);
118        self
119    }
120
121    #[must_use]
122    pub fn order_by_desc(mut self, field: impl AsRef<str>) -> Self {
123        self.query = self.query.order_by_desc(field);
124        self
125    }
126
127    #[must_use]
128    pub fn limit(mut self, limit: u32) -> Self {
129        self.query = self.query.limit(limit);
130        self
131    }
132
133    // ------------------------------------------------------------------
134    // Planning / diagnostics
135    // ------------------------------------------------------------------
136
137    pub fn explain(&self) -> Result<ExplainPlan, QueryError> {
138        self.query.explain()
139    }
140
141    pub fn plan(&self) -> Result<ExecutablePlan<E>, QueryError> {
142        self.query.plan()
143    }
144
145    // ------------------------------------------------------------------
146    // Execution (minimal core surface)
147    // ------------------------------------------------------------------
148
149    /// Execute this delete using the session's policy settings.
150    ///
151    /// All result inspection and projection is performed on `Response<E>`.
152    pub fn execute(&self) -> Result<Response<E>, QueryError>
153    where
154        E: EntityValue,
155    {
156        self.session.execute_query(self.query())
157    }
158
159    /// Execute and return whether any rows were affected.
160    pub fn is_empty(&self) -> Result<bool, QueryError>
161    where
162        E: EntityValue,
163    {
164        Ok(self.execute()?.is_empty())
165    }
166
167    /// Execute and return the number of affected rows.
168    pub fn count(&self) -> Result<u32, QueryError>
169    where
170        E: EntityValue,
171    {
172        Ok(self.execute()?.count())
173    }
174
175    /// Execute and require exactly one affected row.
176    pub fn require_one(&self) -> Result<(), QueryError>
177    where
178        E: EntityValue,
179    {
180        self.execute()?.require_one().map_err(QueryError::Response)
181    }
182
183    /// Execute and require at least one affected row.
184    pub fn require_some(&self) -> Result<(), QueryError>
185    where
186        E: EntityValue,
187    {
188        self.execute()?.require_some().map_err(QueryError::Response)
189    }
190}
191
192impl<C, E> SessionDeleteQuery<'_, C, E>
193where
194    C: CanisterKind,
195    E: EntityKind<Canister = C> + SingletonEntity,
196    E::Key: Default,
197{
198    /// Delete the singleton entity.
199    #[must_use]
200    pub fn only(mut self) -> Self {
201        self.query = self.query.only();
202        self
203    }
204}
icydb_core/db/query/session/delete.rs

icydb_core/db/query/session/
delete.rs
