41 lines
1.2 KiB
Rust
41 lines
1.2 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, 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, 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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select.query().join_as(
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JoinType::InnerJoin,
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unpack_table_ref(&rel.from_tbl),
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SeaRc::clone(&from_tbl),
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join_tbl_on_condition(from_tbl, to_tbl, rel.from_col, rel.to_col),
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);
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}
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select
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}
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}
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