use darling::ToTokens;
use proc_macro2::TokenStream;
use quote::{TokenStreamExt, quote};
use super::options::*;
pub struct PopulateNested<'a> {
column: &'a Column,
ident: &'a syn::Ident,
generics: &'a syn::Generics,
id: &'a syn::Ident,
table_name: &'a str,
events_table_name: &'a str,
repo_types_mod: syn::Ident,
}
impl<'a> PopulateNested<'a> {
pub fn new(column: &'a Column, opts: &'a RepositoryOptions) -> Self {
Self {
column,
ident: &opts.ident,
generics: &opts.generics,
id: opts.id(),
table_name: opts.table_name(),
events_table_name: opts.events_table_name(),
repo_types_mod: opts.repo_types_mod(),
}
}
}
impl ToTokens for PopulateNested<'_> {
fn to_tokens(&self, tokens: &mut TokenStream) {
let ty = self.column.ty();
let ident = self.ident;
let repo_types_mod = &self.repo_types_mod;
let accessor = self.column.parent_accessor();
let query = format!(
"WITH entities AS (SELECT * FROM {} WHERE ({} = ANY($1))) SELECT i.id AS \"entity_id: {}\", e.sequence, e.event, CASE WHEN $2 THEN e.context ELSE NULL::jsonb END as \"context: es_entity::ContextData\", e.recorded_at FROM entities i JOIN {} e ON i.id = e.id ORDER BY e.id, e.sequence",
self.table_name,
self.column.name(),
self.id,
self.events_table_name,
);
let (impl_generics, ty_generics, where_clause) = self.generics.split_for_impl();
tokens.append_all(quote! {
impl #impl_generics es_entity::PopulateNested<#ty> for #ident #ty_generics #where_clause {
async fn populate_in_op<OP, P, __EsErr>(
op: &mut OP,
mut lookup: std::collections::HashMap<#ty, &mut P>,
) -> Result<(), __EsErr>
where
OP: es_entity::AtomicOperation,
P: Parent<<Self as EsRepo>::Entity>,
__EsErr: From<sqlx::Error> + From<es_entity::EntityHydrationError> + Send,
{
let parent_ids: Vec<_> = lookup.keys().collect();
let rows = {
sqlx::query_as!(
#repo_types_mod::Repo__DbEvent,
#query,
parent_ids.as_slice() as &[&#ty],
<#repo_types_mod::Repo__Event as EsEvent>::event_context(),
).fetch_all(op.as_executor()).await?
};
let n = rows.len();
let (mut res, _) = es_entity::EntityEvents::load_n::<<Self as EsRepo>::Entity>(rows.into_iter(), n)?;
Self::load_all_nested_in_op::<_, __EsErr>(op, &mut res).await?;
for entity in res.into_iter() {
let parent = lookup.get_mut(&entity.#accessor).expect("parent not present");
parent.inject_children(std::iter::once(entity));
}
Ok(())
}
}
});
}
}