49 lines
1.5 KiB
Rust
49 lines
1.5 KiB
Rust
use crate::{
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join_tbl_on_condition, unpack_table_ref, EntityTrait, QuerySelect, RelationDef, Select,
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};
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use sea_query::{Alias, Condition, IntoIden, JoinType, SeaRc};
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/// Same as [RelationDef]
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pub type LinkDef = RelationDef;
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/// A Trait for links between Entities
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pub trait Linked {
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#[allow(missing_docs)]
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type FromEntity: EntityTrait;
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#[allow(missing_docs)]
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type ToEntity: EntityTrait;
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/// Link for an Entity
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fn link(&self) -> Vec<LinkDef>;
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/// Find all the Entities that are linked to the Entity
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fn find_linked(&self) -> Select<Self::ToEntity> {
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let mut select = Select::new();
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for (i, mut rel) in self.link().into_iter().rev().enumerate() {
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let from_tbl = Alias::new(format!("r{i}")).into_iden();
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let to_tbl = if i > 0 {
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Alias::new(format!("r{}", i - 1)).into_iden()
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} else {
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unpack_table_ref(&rel.to_tbl)
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};
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let table_ref = rel.from_tbl;
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let mut condition = Condition::all().add(join_tbl_on_condition(
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SeaRc::clone(&from_tbl),
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SeaRc::clone(&to_tbl),
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rel.from_col,
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rel.to_col,
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));
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if let Some(f) = rel.on_condition.take() {
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condition = condition.add(f(SeaRc::clone(&from_tbl), SeaRc::clone(&to_tbl)));
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}
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select
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.query()
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.join_as(JoinType::InnerJoin, table_ref, from_tbl, condition);
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}
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select
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}
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}
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