In #1298, the spec/doc for polymorphic relations was reviewed
**hasX relation**
- `type`: **hasMany**
- `as`: redefines **this** relation's name (optional)
- `model`: **modelTo**
- `polymorphic`:
- typeOf `polymorphic` === `String`
- matching **belongsTo** relation name
- `foreignKey` is generated as `polymorphic + 'Id'`,
- `discriminator` is generated as `polymorphic + 'Type'`
- typeOf `polymorphic` === `Object`
- `as`: **DEPRECATED** should display a warning,
replaced by `selector`
- `selector`: should match **belongsTo** relation name if the
latter is defined with {polymorphic: true}
- (required) if both foreignKey and discriminator
are **NOT** provided
- (extraneous) if both foreignKey and discriminator
are provided
- `foreignKey`: A property of modelTo, representing the fk to
modelFrom's id.
- generated by default as `selector + 'Id'`
- `discriminator`: A property of modelTo, representing the actual
modelFrom to be looked up and defined
dynamically
- generated by default as `selector + 'Type'`
---
**belongsTo relation**
- `type`: **belongsTo**
- `as`: redefines **this** relation's name (optional)
- `model`: **NOT EXPECTED**: should throw an error at
relation validation
- `polymorphic`:
- typeOf `polymorphic` === `Boolean`
- `foreignKey` is generated as `relationName + 'Id'`,
- `discriminator` is generated as `relationName + 'Type'`
- typeOf `polymorphic` === `Object`
- `as`: **DEPRECATED**: should display a warning,
replaced by `selector`
- `selector`:
- (required) if both foreignKey and discriminator
are **NOT** provided
- (extraneous) if both foreignKey and discriminator
are provided
- `foreignKey`: A property of modelTo, representing the fk to
modelFrom's id.
- generated by default as `selector + 'Id'`
- `discriminator`: A property of modelTo, representing the actual
modelFrom to be looked up and defined
dynamically
- generated by default as `selector + 'Type'`
Allow direct save of changes on embedded model to be persisted on
parent document.
Person.embedsOne(Address);
Person.findById(someId)
.then(function(p){
var address = p.addressItem();
address.street = 'new street'
// This will now persist changes on parent document
return address.save();
})
[forward-port of #949]
create() triggers
- before save
- after save
updateById() triggers
- before save
- after save
destroy() triggers
- before delete
- after delete
The implementation here is intentionally left with less features
than the regular DAO methods provide, the goal is to get a partial
(but still useful!) version released soon.
Limitations:
- `before save` & `after save` hooks don't provide `ctx.isNewInstance`
- async validations are not supported yet
- `persist` and `loaded` hooks are not triggered at all
- `before delete` hook does not provide `ctx.where` property and
it's not possible to change the outcome of `destroy()` using this
hook. Note that regular DAO does support this.
- updating embedded instances triggers update of the parent (owning)
model, which is correct and expected. However, the context provided
by `before save` and `after save` hooks on the parent model is sort of
arbitrary and may include wrong/extra data. The same probably applies
to the scenario when deleting embedded instances triggers update of
the parent model.
create() triggers
- before save
- after save
udpate() triggers
- before save
- after save
destroy() triggers
- before delete
- after delete
The implementation here is intentionally left with less features
than the regular DAO methods provide, the goal is to get a partial
(but still useful!) version released soon.
When a callback is omitted from a method on a model relation that
supports promises, return that promise. This includes all the standard
DAO methods, as well as any user-defined methods that return promises.
e.g.:
mylist.todos.create({name: 'Item 1'}) // returns Promise
This API will use native ES6 promises if available. If not available,
or to force the use of another Promise library, you must assign the
global.Promise object.
e.g.:
global.Promise = require('bluebird')
Relations affected:
- BelongsTo
- HasOne
- HasMany
- HasManyThrough
- HasAndBelongsToMany
- ReferencesMany
- EmbedsOne
Exceptions:
The EmbedsMany relation has not been promisified, because most of the
methods return synchronous values.
The base relation getter method [e.g.: mylist.todos()] has not been
promisified, due to its default caching behavior.
New Methods:
- getAsync(condition, cb)
A new method "getAsync()" has been added to all relations except
EmbedsMany, which always fetches from the datasource rather than from
the cache. It takes an optional "where" condition (except for HasOne
and BelongsTo) and an optional callback. If the callback is omitted,
a Promise is returned.
This commit is dropping lodash in favour of hand-written implementation
based on ES5 Array methods. As a result, the size of the (unminified)
loopback browser bundle is decreased by approx 360KB.
So hasOne#create could take advantage from optimized findOrCreate,
which can avoid multiple creation among concurrent requests.
Signed-off-by: Clark Wang <clark.wangs@gmail.com>
Jürg Lehni
ebarault
Waldemar Zahn
Miroslav Bajtoš
Amir Jafarian
Candy
Dimitris Halatsis
Ryan Graham
sklyukin
Satyadeep
Laurent Villeneuve
Raymond Feng
Patrick Perini
Dmitry Manannikov
ningsuhen
Partap Davis
Fabien Franzen
Miroslav Bajtoš
Raymond Feng
Clark Wang
Bryan Clark