use super::*;
#[derive(Debug, Clone)]
pub struct BelongsTo<E: Model> {
pub foreign_key: &'static str,
pub owner_key: &'static str,
cached: Option<Box<E>>,
loaded: bool,
fk_value: Option<serde_json::Value>,
#[cfg(feature = "entity-manager")]
entity_manager: Option<Arc<crate::entity_manager::EntityManager>>,
#[cfg(feature = "entity-manager")]
query_db: Option<crate::database::Database>,
_marker: PhantomData<E>,
}
impl<E: Model> BelongsTo<E> {
fn ensure_configured(&self) -> Result<()> {
ensure_relation_configured("BelongsTo", &[self.foreign_key, self.owner_key])
}
pub fn new(foreign_key: &'static str, owner_key: &'static str) -> Self {
Self {
foreign_key,
owner_key,
cached: None,
loaded: false,
fk_value: None,
#[cfg(feature = "entity-manager")]
entity_manager: None,
#[cfg(feature = "entity-manager")]
query_db: None,
_marker: PhantomData,
}
}
pub fn with_fk_value(mut self, fk: serde_json::Value) -> Self {
self.fk_value = Some(fk);
self
}
#[cfg(feature = "entity-manager")]
#[doc(hidden)]
pub fn with_entity_manager(
mut self,
entity_manager: Arc<crate::entity_manager::EntityManager>,
) -> Self {
self.entity_manager = Some(entity_manager);
self
}
#[cfg(feature = "entity-manager")]
fn query_builder(&self) -> QueryBuilder<E> {
if let Some(entity_manager) = &self.entity_manager {
E::query_with(entity_manager.database())
} else if let Some(db) = &self.query_db {
E::query_with(db)
} else {
E::query()
}
}
#[cfg(feature = "entity-manager")]
#[doc(hidden)]
pub fn attach_query_database(&mut self, database: &crate::database::Database) {
self.query_db = Some(database.clone());
}
#[doc(hidden)]
pub fn set_cached(&mut self, model: Option<E>) {
self.cached = model.map(Box::new);
self.loaded = true;
}
#[doc(hidden)]
pub fn preserve_runtime_state_from(&mut self, previous: &Self) {
let same_relation = self.foreign_key == previous.foreign_key
&& self.owner_key == previous.owner_key
&& self.fk_value == previous.fk_value;
preserve_cached_value(
&mut self.cached,
&previous.cached,
previous.fk_value.is_none(),
same_relation,
);
if previous.fk_value.is_none() && !self.loaded {
self.loaded = previous.loaded;
}
#[cfg(feature = "entity-manager")]
if same_relation {
if self.entity_manager.is_none() {
self.entity_manager = previous.entity_manager.clone();
}
if self.query_db.is_none() {
self.query_db = previous.query_db.clone();
}
}
if same_relation && !self.loaded {
self.loaded = previous.loaded;
}
}
pub async fn load(&self) -> Result<Option<E>> {
#[cfg(feature = "entity-manager")]
if self.loaded && self.entity_manager.is_some() {
return Ok(self.cached.as_deref().cloned());
}
let can_query = {
#[cfg(feature = "entity-manager")]
{
has_active_database() || self.entity_manager.is_some() || self.query_db.is_some()
}
#[cfg(not(feature = "entity-manager"))]
{
has_active_database()
}
};
if can_query && self.ensure_configured().is_ok() {
if let Some(fk) = self.fk_value.as_ref() {
let fk = require_scalar_relation_key(fk, "BelongsTo::load")?;
let query = {
#[cfg(feature = "entity-manager")]
{
self.query_builder()
}
#[cfg(not(feature = "entity-manager"))]
{
E::query()
}
};
return query.where_eq(self.owner_key, fk.clone()).first().await;
}
}
if self.loaded {
return Ok(self.cached.as_deref().cloned());
}
self.ensure_configured()?;
let fk = self
.fk_value
.as_ref()
.ok_or_else(|| Error::query(String::from("Foreign key value not set for relation")))?;
let fk = require_scalar_relation_key(fk, "BelongsTo::load")?;
let query = {
#[cfg(feature = "entity-manager")]
{
self.query_builder()
}
#[cfg(not(feature = "entity-manager"))]
{
E::query()
}
};
query.where_eq(self.owner_key, fk.clone()).first().await
}
pub async fn load_with<F>(&self, constraint_fn: F) -> Result<Option<E>>
where
F: FnOnce(QueryBuilder<E>) -> QueryBuilder<E> + Send,
{
self.ensure_configured()?;
let fk = self
.fk_value
.as_ref()
.ok_or_else(|| Error::query(String::from("Foreign key value not set for relation")))?;
let fk = require_scalar_relation_key(fk, "BelongsTo::load_with")?;
let query = {
#[cfg(feature = "entity-manager")]
{
self.query_builder()
}
#[cfg(not(feature = "entity-manager"))]
{
E::query()
}
}
.where_eq(self.owner_key, fk.clone());
constraint_fn(query).first().await
}
pub async fn exists(&self) -> Result<bool> {
self.ensure_configured()?;
let fk = self
.fk_value
.as_ref()
.ok_or_else(|| Error::query(String::from("Foreign key value not set for relation")))?;
let fk = require_scalar_relation_key(fk, "BelongsTo::exists")?;
let query = {
#[cfg(feature = "entity-manager")]
{
self.query_builder()
}
#[cfg(not(feature = "entity-manager"))]
{
E::query()
}
};
query.where_eq(self.owner_key, fk.clone()).exists().await
}
pub fn as_mut(&mut self) -> Option<&mut E> {
self.cached.as_deref_mut()
}
pub fn is_loaded(&self) -> bool {
self.loaded
}
pub fn get_cached(&self) -> Option<&E> {
cached_ref(&self.cached)
}
#[cfg(feature = "entity-manager")]
pub async fn load_in_entity_manager(
&mut self,
entity_manager: &Arc<crate::entity_manager::EntityManager>,
) -> Result<Option<&E>>
where
E: crate::internal::InternalModel
+ crate::entity_manager::TideEntityManagerMeta
+ Clone
+ Send
+ Sync
+ 'static,
{
if self.loaded {
if let Some(cached) = self.cached.as_deref() {
entity_manager.put(cached.clone());
}
self.entity_manager = Some(entity_manager.clone());
return Ok(self.cached.as_deref());
}
self.ensure_configured()?;
let fk = self
.fk_value
.as_ref()
.ok_or_else(|| Error::query(String::from("Foreign key value not set for relation")))?;
let fk = require_scalar_relation_key(fk, "BelongsTo::load_in_entity_manager")?;
let loaded = if let Some(cached) = entity_manager.find_by_field::<E>(self.owner_key, fk)? {
Some(cached)
} else {
E::query_with(entity_manager.database())
.where_eq(self.owner_key, fk.clone())
.first()
.await?
};
self.cached = match loaded {
Some(entity) => Some(Box::new(entity_manager.register(entity).await)),
None => None,
};
self.loaded = true;
self.entity_manager = Some(entity_manager.clone());
Ok(self.cached.as_deref())
}
}
impl<E: Model> Default for BelongsTo<E> {
fn default() -> Self {
Self {
foreign_key: "",
owner_key: "",
cached: None,
loaded: false,
fk_value: None,
#[cfg(feature = "entity-manager")]
entity_manager: None,
#[cfg(feature = "entity-manager")]
query_db: None,
_marker: PhantomData,
}
}
}
impl<E: Model + Serialize> Serialize for BelongsTo<E> {
fn serialize<S>(&self, serializer: S) -> std::result::Result<S::Ok, S::Error>
where
S: Serializer,
{
self.cached.serialize(serializer)
}
}
impl<'de, E: Model> Deserialize<'de> for BelongsTo<E> {
fn deserialize<D>(deserializer: D) -> std::result::Result<Self, D::Error>
where
D: Deserializer<'de>,
{
let cached = Option::<E>::deserialize(deserializer)?;
let loaded = cached.is_some();
Ok(Self {
cached: cached.map(Box::new),
loaded,
..Self::default()
})
}
}
#[cfg(all(test, feature = "entity-manager"))]
#[path = "../../../tests/unit/direct_entity_manager_relation_tests.rs"]
mod entity_manager_tests;
#[cfg(feature = "entity-manager")]
impl<E> crate::entity_manager::EntityManagerLoad for BelongsTo<E>
where
E: crate::internal::InternalModel
+ crate::entity_manager::TideEntityManagerMeta
+ Model
+ Clone
+ Send
+ Sync
+ 'static,
{
type Output<'a>
= Option<&'a E>
where
Self: 'a;
fn load_with_entity_manager<'a>(
&'a mut self,
entity_manager: &'a Arc<crate::entity_manager::EntityManager>,
) -> std::pin::Pin<Box<dyn std::future::Future<Output = Result<Self::Output<'a>>> + Send + 'a>>
{
Box::pin(async move { self.load_in_entity_manager(entity_manager).await })
}
}