Sequelize - include all association filtered results - node.js

Question

I have a a model called Post and Country. When I filter by a particular country Id, it returns correctly filtered posts but only returns that specific country in the response and discards all the other countries associated with the Post. How can I include and retain all the countries associated with the post in the response?
Post.js
class Post extends Sequelize.Model {
static init(sequelize, DataTypes) {
return super.init(
{
id: {
type: Sequelize.INTEGER,
primaryKey: true,
autoIncrement: true
},
number: {
type: Sequelize.INTEGER,
validate: {
isInt: true
}
},
}
);
static associate(models) {
this.myAssociation = this.belongsToMany(models.Country,
{through: "CountriesImpacted", foreignKey: "id"});
}
}
module.exports = Incident;
Country.js
class Country extends Sequelize.Model {
static init(sequelize, DataTypes) {
return super.init(
{
id: {
allowNull: false,
autoIncrement: true,
primaryKey: true,
type: Sequelize.INTEGER
},
name: {
type: Sequelize.STRING,
primaryKey: true,
unique: true
}
}, {sequelize, modelName: 'country', tableName: 'Countries'}
)
}
}
module.exports = Country;
routes.js
Post.findAndCountAll({
attributes: { exclude: ["createdAt", "updatedAt"] },
order: [Country, "name", "asc"],
include: [{
model: Country,
where: { id: country_ids_from_request }
}],
where: filters,
distinct: true,
offset: offset,
limit: limit
})
example output
{
'0': {
id: 1,
number: 1203021,
countries: [
{
id: 6,
name: 'Australia',
CountriesImpacted: {
id: 1,
countryId: 6
}
},
{
id: 7,
name: 'New Zealand',
CountriesImpacted: {
id: 1,
countryId: 7
}
}
]
}
}
when I filter by country id 6, the repsonse will discard New Zealand...

Answer 1

It requires a sub-query to fetch the eligible Post model. It will look like following
return Post.findAll({
include: [
{
model: Country
}
],
where: {
id : {
[Sequelize.Op.in] : [Sequelize.literal(`(SELECT posts.id FROM posts INNER JOIN countries ON countries.postId = posts.id WHERE ${COUNTRY_ID} IN (countries.id))`)] // Subquery...
}
}
})
Here i assume following
Your Post schema name is posts.
Your Country schema name is countries.
Country has a postsId foreign key REFERENCES TO Post.
If you are not comfortable with having sub-query inside your project while using Sequelize (ORM), then you have to execute two query, first fetching all the eligible Posts then fetch desired for those Posts.