Sequelize include same association twice with different criteria - node.js

Question

Say I have a table suppliers, which is associated to tags through another table suppliers_tags. So my model looks like this:
const Supplier = Sequelize.define('suppliers', {
id: { type: Sequelize.INTEGER, primaryKey: true },
name: Sequelize.STRING,
});
const SupplierTag = Sequelize.define('suppliers_tags', {
id: { type: Sequelize.INTEGER, primaryKey: true },
supplier_id: { type: Sequelize.INTEGER, references: { model: 'suppliers', key: 'id' } },
tag_id: { type: Sequelize.INTEGER, references: { model: 'suppliers', key: 'id' } },
});
const Tag = Sequelize.define('tags', {
id: { type: Sequelize.INTEGER, primaryKey: true },
name: Sequelize.STRING,
type: Sequelize.ENUM('food', 'drink'),
});
The associations look like this:
Supplier.belongsToMany(Tag, { as: 'tags', through: 'suppliers_tags', foreignKey: 'supplier_id' });
Tag.belongsToMany(Supplier, { as: 'supplierTag', through: 'suppliers_tags', foreignKey: 'tag_id' });
Let's say I have the following data in the database:
suppliers:
id name
1 Supplier1
2 Supplier2
3 Supplier3
tags:
id name type
1 Food1 food
2 Vegan food
3 Vegan drink
4 Food2 food
(I purposely named two tags the same, as for this application, it is important that tags with different types can have the same name.)
suppliers_tags
id supplier_id tag_id
1 1 1
2 1 3
3 1 2
4 2 1
5 2 4
6 3 2
Now I can do the following query:
Supplier.findAll({
include: [
{
model: Tag,
as: 'tags',
where: {
[Op.and]: [
{ type: 'food' },
{ name: 'Vegan' },
],
},
},
],
});
This returns Supplier1 and Supplier3, correctly joining on suppliers_tags and tags and filtering the tags table to include ones of type 'food' and name 'Vegan'.
Now, what if I want to search for suppliers where both the following conditions hold:
The supplier has an associated tag which is of type food and name Food1
The supplier has an associated tag which is of type drink and name Vegan
Naively (?), I tried the following:
Supplier.findAll({
include: [
{
model: Tag,
as: 'tags_food',
where: {
[Op.and]: [
{ type: 'food' },
{ name: 'Food1' },
],
},
},
{
model: Tag,
as: 'tags_drink',
where: {
[Op.and]: [
{ type: 'drink' },
{ name: 'Vegan' },
],
},
},
],
});
This tries to join the tags table twice, but neglecting to add aliases, resulting in the following error:
SequelizeEagerLoadingError: tags is associated to suppliers multiple times. To identify the correct association, you must use the 'as' keyword to specify the alias of the association you want to include.
Right, so it seems like the as options on the include didn't have the desired effect. What if I modify the associations to be the following:
Supplier.belongsToMany(Tag, { as: 'tags_drink', through: 'suppliers_tags', foreignKey: 'supplier_id' });
Supplier.belongsToMany(Tag, { as: 'tags_food', through: 'suppliers_tags', foreignKey: 'supplier_id' });
Tag.belongsToMany(Supplier, { as: 'supplierTag', through: 'suppliers_tags', foreignKey: 'tag_id' });
Now, if I run the same findAll query, it generates the following SQL:
SELECT
"suppliers".*
,"tags_food"."id" AS "tags_food.id"
,"tags_food"."name" AS "tags_food.name"
,"tags_food"."type" AS "tags_food.type"
,"tags_food->suppliers_tags"."supplier_id" AS "tags_food.suppliers_tags.supplier_id"
,"tags_food->suppliers_tags"."tag_id" AS "tags_food.suppliers_tags.tag_id"
,"tags_drink"."id" AS "tags_drink.id"
,"tags_drink"."name" AS "tags_drink.name"
,"tags_drink"."type" AS "tags_drink.type"
,"tags_drink->suppliers_tags"."supplier_id" AS "tags_drink.suppliers_tags.supplier_id"
,"tags_drink->suppliers_tags"."tag_id" AS "tags_drink.suppliers_tags.tag_id"
FROM (
SELECT
"suppliers"."id"
,"suppliers"."name"
FROM "suppliers" AS "suppliers"
WHERE (
SELECT "suppliers_tags"."supplier_id"
FROM "suppliers_tags" AS "suppliers_tags"
INNER JOIN "tags" AS "tag" ON "suppliers_tags"."tagId" = "tag"."id"
AND ("tag"."type" = 'food' AND "tag"."name" = 'Food1')
WHERE ("suppliers"."id" = "suppliers_tags"."supplier_id")
LIMIT 1
) IS NOT NULL
AND (
SELECT "suppliers_tags"."supplier_id"
FROM "suppliers_tags" AS "suppliers_tags"
INNER JOIN "tags" AS "tag" ON "suppliers_tags"."tag_id" = "tag"."id"
AND ("tag"."type" = 'drink' AND "tag"."name" = 'Vegan')
WHERE ("suppliers"."id" = "suppliers_tags"."supplier_id")
LIMIT 1
) IS NOT NULL
) AS "suppliers"
INNER JOIN (
"suppliers_tags" AS "tags_food->suppliers_tags"
INNER JOIN "tags" AS "tags_food"
ON "tags_food"."id" = "tags_food->suppliers_tags"."tagId"
) ON "suppliers"."id" = "tags_food->suppliers_tags"."supplier_id"
AND ("tags_food"."type" = 'food' AND "tags_food"."name" = 'Food1')
INNER JOIN (
"suppliers_tags" AS "tags_drink->suppliers_tags"
INNER JOIN "tags" AS "tags_drink"
ON "tags_drink"."id" = "tags_drink->suppliers_tags"."tag_id"
) ON "suppliers"."id" = "tags_drink->suppliers_tags"."supplier_id"
AND ("tags_drink"."type" = 'drink' AND "tags_drink"."name" = 'Vegan')
ORDER BY "suppliers"."id"
This is correct and what I need, except for one error: the foreign key tag_id has been switched to tagId (?!) in the case of the tags_food join. This then of course fails with the following error:
SequelizeDatabaseError: column tags_food->suppliers_tags.tagId does not exist
Notice that the correct foreign key tag_id was generated in the join on tags_drink by Sequelize.
If I switch around the relation definitions, i.e.:
Supplier.belongsToMany(Tag, { as: 'tags_food', through: 'suppliers_tags', foreignKey: 'supplier_id' });
Supplier.belongsToMany(Tag, { as: 'tags_drink', through: 'suppliers_tags', foreignKey: 'supplier_id' });
Tag.belongsToMany(Supplier, { as: 'supplierTag', through: 'suppliers_tags', foreignKey: 'tag_id' });
Then tag_id is produced successfully for the tags_food join and the weird tagId is produced for the tags_drink join.
Can I put this down to another basic flaw with Sequelize, or:
Is there a defined way of joining the same relation twice on different criteria in Sequelize?