119 lines
3.6 KiB
Rust
119 lines
3.6 KiB
Rust
// Copyright 2018 Mozilla
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use
|
|
// this file except in compliance with the License. You may obtain a copy of the
|
|
// License at http://www.apache.org/licenses/LICENSE-2.0
|
|
// Unless required by applicable law or agreed to in writing, software distributed
|
|
// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
|
|
// CONDITIONS OF ANY KIND, either express or implied. See the License for the
|
|
// specific language governing permissions and limitations under the License.
|
|
|
|
use std::collections::{
|
|
BTreeMap,
|
|
BTreeSet,
|
|
};
|
|
|
|
use mentat_core::{
|
|
Binding,
|
|
Entid,
|
|
Schema,
|
|
StructuredMap,
|
|
TypedValue,
|
|
ValueRc,
|
|
};
|
|
|
|
use mentat_query::{
|
|
PullAttributeSpec,
|
|
};
|
|
|
|
use mentat_query_pull::{
|
|
Puller,
|
|
};
|
|
|
|
use errors::Result;
|
|
|
|
use super::{
|
|
Index,
|
|
rusqlite,
|
|
};
|
|
|
|
#[derive(Clone, Debug)]
|
|
pub(crate) struct PullOperation(pub(crate) Vec<PullAttributeSpec>);
|
|
|
|
#[derive(Clone, Copy, Debug)]
|
|
pub(crate) struct PullIndices {
|
|
pub(crate) sql_index: Index, // SQLite column index.
|
|
pub(crate) output_index: usize,
|
|
}
|
|
|
|
impl PullIndices {
|
|
fn zero() -> PullIndices {
|
|
PullIndices {
|
|
sql_index: 0,
|
|
output_index: 0,
|
|
}
|
|
}
|
|
}
|
|
|
|
#[derive(Debug)]
|
|
pub(crate) struct PullTemplate {
|
|
pub(crate) indices: PullIndices,
|
|
pub(crate) op: PullOperation,
|
|
}
|
|
|
|
pub(crate) struct PullConsumer<'schema> {
|
|
indices: PullIndices,
|
|
schema: &'schema Schema,
|
|
puller: Puller,
|
|
entities: BTreeSet<Entid>,
|
|
results: BTreeMap<Entid, ValueRc<StructuredMap>>,
|
|
}
|
|
|
|
impl<'schema> PullConsumer<'schema> {
|
|
pub(crate) fn for_puller(puller: Puller, schema: &'schema Schema, indices: PullIndices) -> PullConsumer<'schema> {
|
|
PullConsumer {
|
|
indices: indices,
|
|
schema: schema,
|
|
puller: puller,
|
|
entities: Default::default(),
|
|
results: Default::default(),
|
|
}
|
|
}
|
|
|
|
pub(crate) fn for_template(schema: &'schema Schema, template: &PullTemplate) -> Result<PullConsumer<'schema>> {
|
|
let puller = Puller::prepare(schema, template.op.0.clone())?;
|
|
Ok(PullConsumer::for_puller(puller, schema, template.indices))
|
|
}
|
|
|
|
pub(crate) fn for_operation(schema: &'schema Schema, operation: &PullOperation) -> Result<PullConsumer<'schema>> {
|
|
let puller = Puller::prepare(schema, operation.0.clone())?;
|
|
Ok(PullConsumer::for_puller(puller, schema, PullIndices::zero()))
|
|
}
|
|
|
|
pub(crate) fn collect_entity<'a, 'stmt>(&mut self, row: &rusqlite::Row<'a, 'stmt>) -> Entid {
|
|
let entity = row.get(self.indices.sql_index);
|
|
self.entities.insert(entity);
|
|
entity
|
|
}
|
|
|
|
pub(crate) fn pull(&mut self, sqlite: &rusqlite::Connection) -> Result<()> {
|
|
let entities: Vec<Entid> = self.entities.iter().cloned().collect();
|
|
self.results = self.puller.pull(self.schema, sqlite, entities)?;
|
|
Ok(())
|
|
}
|
|
|
|
pub(crate) fn expand(&self, bindings: &mut [Binding]) {
|
|
if let Binding::Scalar(TypedValue::Ref(id)) = bindings[self.indices.output_index] {
|
|
if let Some(pulled) = self.results.get(&id).cloned() {
|
|
bindings[self.indices.output_index] = Binding::Map(pulled);
|
|
} else {
|
|
bindings[self.indices.output_index] = Binding::Map(ValueRc::new(Default::default()));
|
|
}
|
|
}
|
|
}
|
|
|
|
// TODO: do we need to include empty maps for entities that didn't match any pull?
|
|
pub(crate) fn into_coll_results(self) -> Vec<Binding> {
|
|
self.results.values().cloned().map(|vrc| Binding::Map(vrc)).collect()
|
|
}
|
|
}
|