Sails.js one to many association with postgreSQL: column does not exist - sails.js

Question

I need some help with associations in sails 0.12.13 with postgresql.
I have an "App" model and a "Membership" model. Relation should be one to many (one app can be associated with many relationships).
This is the App model db table schema (table is called "apps"):
Table "public.apps"
Column | Type | Modifiers
------------+-----------------------------+---------------------------------------------------
id | integer | not null default nextval('apps_id_seq'::regclass)
name | character varying | not null
Indexes:
"apps_pkey" PRIMARY KEY, btree (id)
"apps_name_key" UNIQUE CONSTRAINT, btree (name)
Referenced by:
TABLE "memberships" CONSTRAINT "app_fk" FOREIGN KEY (app_id) REFERENCES apps(id) ON UPDATE RESTRICT ON DELETE CASCADE
And this is memberships:
Table "public.memberships"
Column | Type | Modifiers
------------+-----------------------------+----------------------------------------------------------
id | integer | not null default nextval('memberships_id_seq'::regclass)
app_id | integer | not null
Foreign-key constraints:
"app_fk" FOREIGN KEY (app_id) REFERENCES apps(id) ON UPDATE RESTRICT ON DELETE CASCADE
in my user model, i have this:
module.exports = {
tableName: 'apps',
autoCreatedAt: false,
autoUpdatedAt: false,
attributes: {
name: { type: 'string', unique: true, required: true, alphanumericdashed: true },
memberships: { collection: 'memberships', model: 'Membership' },
}
}
And this is the Membership model:
module.exports = {
tableName: 'memberships',
autoCreatedAt: false,
autoUpdatedAt: false,
attributes: {
app: { model: 'app', columnName: 'app_id' },
},
};
When I try to query an app and get its memberships:
App.find({ id: 1 }).populate('memberships').exec((err, app) => {
if (err) throw err;
console.log(app.memberships);
});
I get this error:
Error (E_UNKNOWN) :: Encountered an unexpected error
error: column apps.memberships does not exist
at Connection.parseE (/usr/src/app/node_modules/sails-postgresql/node_modules/pg/lib/connection.js:539:11)
at Connection.parseMessage (/usr/src/app/node_modules/sails-postgresql/node_modules/pg/lib/connection.js:366:17)
at Socket.<anonymous> (/usr/src/app/node_modules/sails-postgresql/node_modules/pg/lib/connection.js:105:22)
at emitOne (events.js:115:13)
at Socket.emit (events.js:210:7)
at addChunk (_stream_readable.js:252:12)
at readableAddChunk (_stream_readable.js:239:11)
at Socket.Readable.push (_stream_readable.js:197:10)
at TCP.onread (net.js:589:20)
Looks like the association is not "enabled" and waterline is searching for an actual column "membership" in my model. Can anybody explain me what I am doing wrong? thx

Answer 1

According to the documentation, I would guess that you have a bad association.
// App.js
module.exports = {
tableName: 'apps',
autoCreatedAt: false,
autoUpdatedAt: false,
attributes: {
name: {
type: 'string',
unique: true,
required: true,
alphanumericdashed: true
},
memberships: {
collection: 'membership', // <-- changed to singular (as your model should be)
via: 'app' // <-- use "via" instead of "model"
},
}
}
// Membership.js
module.exports = {
tableName: 'memberships',
autoCreatedAt: false,
autoUpdatedAt: false,
attributes: {
app: {
model: 'app'
// <-- removed the "columnName" here
},
},
};
Also, convention generally says name your model as a singular instance. For example, its "User.js" and not "Users.js". It's valid to refer to the collection as a plural. I made some changes in your naming, but you'll have to see how that affects your files (since you didn't give those names).