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Export SailsJS model schema as JSON

The goal is to take model schema and export it somewhere as JSON, take that json and make a dynamic form in Angular.
Basically main problem which I see here is to get model, and generate output which will be important for generating reactive form in Angular.
For example:
module.exports = {
attributes: {
nameOnMenu: { type: 'string', required: true },
price: { type: 'string', required: true },
percentRealMeat: { type: 'number' },
numCalories: { type: 'number' },
},
};
So final output would look like:
[
{ nameOnMenu: { type: 'string', required: true }},
{ price: { type: 'string', required: true }},
{ percentRealMeat: { type: 'number', required: false }},
{ numCalories: { type: 'number', required: false }},
]
Based on this output, i will go through all and generate form.

I'm not sure that I really understand the question that you are asking here but let me take a bash at trying to provide an answer.
I can think of two ways that you could achieve it:
1.) Use server rendered local data to include the desired result for use on the front end.
2.) Make an API request from the front end for the desired result.
In your resulting controller/action you can get the model attributes in various ways. I can think of one:
const { resolve } = require('path');
// Portable relative path based on code being in
// config/bootstrap.js file so adjust as required
const modelDefinition = require(resolve(__dirname, '..', 'api', 'models', 'NameOfModel.js')).attributes;
console.log(modelDefinition);
{ name:
{ type: 'string',
required: true,
validations: { isNotEmptyString: true },
autoMigrations:
{ columnType: 'varchar(255)',
unique: false,
autoIncrement: false } },
...etc,
}
For completeness, you would need to factor in a few things regarding the model settings and model attributes in order to get an accurate output, for instance, whether or not the table includes an updatedAt field.
Ultimately, you can marshal this data as you see fit with vanilla Javascript/Node in order to obtain your desired result but I will leave that to you.
As another user has pointed out, I'm also not sure that you will find an officially supported solution for completely reactive data using Angular and Sails, I assume that this will require a bit of engineering in order for your to create something that is suitable for your needs.

Sequelize: how to do a WHERE condition on joined table with left outer join

My database model is as follows:
An employee drives one or zero vehicles
A vehicle can be driven by one or more employees
A vehicle has a model type that tells us it's fuel type amongst other things.
I'd like sequelize to fetch me all employees where they don't drive a vehicle, or if they do then the vehicle is not diesel.
So where VehicleID is null OR Vehicle.VehicleModel.IsDiesel = false
My current code is as follows:
var employee = sequelize.define('employee', {
ID: Sequelize.INTEGER,
VehicleID: Sequelize.INTEGER
});
var vehicle = sequelize.define('vehicle', {
ID: Sequelize.INTEGER,
ModelID: Sequelize.INTEGER
});
var vehicleModel = sequelize.define('vehicleModel', {
ID: Sequelize.INTEGER,
IsDiesel: Sequelize.BOOLEAN
});
employee.belongsTo(vehicle);
vehicle.belongsTo(vehicleModel);
If I run the following:
options.include = [{
model: model.Vehicle,
attributes: ['ID', 'ModelID'],
include: [
{
model: model.VehicleModel,
attributes: ['ID', 'IsDiesel']
}]
}];
employee
.findAll(options)
.success(function(results) {
// do stuff
});
Sequelize does a left outer join to get me the included tables. So I get employees who drive vehicles and who don't.
As soon as I add a where to my options:
options.include = [{
model: model.Vehicle,
attributes: ['ID', 'ModelID'],
include: [
{
model: model.VehicleModel,
attributes: ['ID', 'IsDiesel']
where: {
IsDiesel: false
}
}]
}];
Sequelize now does an inner join to get the included tables.
This means that I only get employees who drive a vehicle and the vehicle is not diesel. The employees who don't drive a vehicle are excluded.
Fundamentally, I need a way of telling Sequelize to do a left outer join and at the same time have a where condition that states the column from the joined table is false or null.
EDIT:
It turns out that the solution was to use required: false, as below:
options.include = [{
model: model.Vehicle,
attributes: ['ID', 'ModelID'],
include: [
{
model: model.VehicleModel,
attributes: ['ID', 'IsDiesel']
where: {
IsDiesel: false
},
required: false
}],
required: false
}];
I had already tried putting the first 'required:false' but I missed out on putting the inner one. I thought it wasn't working so I gave up on that approach. Dajalmar Gutierrez's answer made me realise I needed both for it to work.

When you add a where clause, sequelize automatically adds a required: true clause to your code.
Adding required: false to your include segment should solve the problem
Note: you should check this issue iss4019

Eager loading
When you are retrieving data from the database there is a fair chance that you also want to get associations with the same query - this is called eager loading. The basic idea behind that, is the use of the attribute include when you are calling find or findAll.
when you set
required: false
will do
LEFT OUTER JOIN
when
required: true
will do
INNER JOIN
for more detail docs.sequelizejs eager-loading

Querying association tables in Sequelize

I have two tables (users and games) joined by an association table (game_players), creating a many-to-many relationship:
models.Game.belongsToMany(models.User, { through: models.GamePlayer, as: 'players' });
models.User.belongsToMany(models.Game, { through: models.GamePlayer, foreignKey: 'user_id' });
In addition to the foreign keys user_id and game_id, game_players has a few extra columns for link-specific data:
sequelize.define('game_player', {
isReady: {
defaultValue: false,
type: Sequelize.BOOLEAN,
field: 'is_ready'
},
isDisabled: {
defaultValue: false,
type: Sequelize.BOOLEAN,
field: 'is_disabled'
},
powerPreferences: {
type: Sequelize.TEXT,
field: 'power_preferences'
},
power: {
type: Sequelize.STRING(2),
defaultValue: '?'
}
}, {
underscored: true
});
Suppose I want to fetch a game and eagerly load active players. This was my first effort:
db.models.Game.findAll({
include: [{
model: db.models.User,
as: 'players',
where: { 'game_player.isDisabled': false }
}]
}).nodeify(cb);
This generates the following SQL, which throws the error Column players.game_player.isDisabled does not exist:
SELECT "game"."id",
"game"."name",
"game"."description",
"game"."variant",
"game"."status",
"game"."move_clock" AS "moveClock",
"game"."retreat_clock" AS "retreatClock",
"game"."adjust_clock" AS "adjustClock",
"game"."max_players" AS "maxPlayers",
"game"."created_at",
"game"."updated_at",
"game"."gm_id",
"game"."current_phase_id",
"players"."id" AS "players.id",
"players"."email" AS "players.email",
"players"."temp_email" AS "players.tempEmail",
"players"."password" AS "players.password",
"players"."password_salt" AS "players.passwordSalt",
"players"."action_count" AS "players.actionCount",
"players"."failed_action_count" AS "players.failedActionCount",
"players"."created_at" AS "players.created_at",
"players"."updated_at" AS "players.updated_at",
"players.game_player"."is_ready" AS
"players.game_player.isReady",
"players.game_player"."is_disabled" AS
"players.game_player.isDisabled",
"players.game_player"."power_preferences" AS
"players.game_player.powerPreferences",
"players.game_player"."power" AS "players.game_player.power",
"players.game_player"."created_at" AS
"players.game_player.created_at",
"players.game_player"."updated_at" AS
"players.game_player.updated_at",
"players.game_player"."game_id" AS
"players.game_player.game_id",
"players.game_player"."user_id" AS
"players.game_player.user_id"
FROM "games" AS "game"
INNER JOIN ("game_players" AS "players.game_player"
INNER JOIN "users" AS "players"
ON "players"."id" = "players.game_player"."user_id")
ON "game"."id" = "players.game_player"."game_id"
AND "players"."game_player.isdisabled" = false;
Clearly Sequelize is wrapping my constraint alias with incorrect quotes: 'players'.'game_player.isdisabled' should be 'players.game_player'.isdisabled. How can I revise my Sequelize code above to correctly query this column?

I got it, but only through manually browsing the repository's closed tickets and coming upon #4880.
Clauses using joined table columns that don't work out of the box can be wrapped in $. I honestly don't understand its magic, because I swear I don't see any documentation for it. Modifying my query above achieved what I wanted:
db.models.Game.findAll({
include: [{
model: db.models.User,
as: 'players',
where: { '$players.game_player.is_disabled$': false }
}]
}).nodeify(cb);

After searching around, I found that through.where can also be used:
db.models.Game.findAll({
include: [{
model: db.models.User,
as: 'players',
through: { where: { isDisabled: false } }
}]
})
Reference:
Is it possible to filter a query by the attributes in the association table with sequelize?
Eager loading with Many-to-Many relationships

Your query should be on the join table with the 'where' condition, and then you should use the 'include' clause to include the two other models, like this:
db.models.GamePlayer.findAll({
where: {isDisabled: false},
attributes: [],
include: [models.User, models.Game]
}).then(function(result){
....
});

Preventing duplicate records in Mongoose

I'm fairly new to MongoDb / Mongoose, more used to SQL Server or Oracle.
I have a fairly simple Schema for an event.
EventSchema.add({
pkey: { type: String, unique: true },
device: { type: String, required: true },
name: { type: String, required: true },
owner: { type: String, required: true },
description: { type: String, required: true },
});
I was looking at Mongoose Indexes which shows two ways of doing it, I used the field definition.
I also have a very simple API that accepts a POST and calls create on this collection to insert the record.
I wrote a test that checks that the insert of a record with the same pkey should not happen and that the unique:true is functioning. I already have a set of events that I read into an array so I just POST the first of these events again and see what happens, I expected that mongo DB would throw the E11000 duplicate key error, but this did not happen.
var url = 'api/events';
var evt = JSON.parse(JSON.stringify(events[0]));
// POST'ed new record won't have an _id yet
delete evt._id;
api.post(url)
.send(evt)
.end(err, res) {
err.should.exist;
err.code.should.equal(11000);
});
The test fails, there is no error and a duplicate record is inserted.
When I take a look at the collection I can see two records, both with the same pkey (the original record and the copy that I posted for the test). I do notice that the second record has the same creation date as the first but a later modified date.
(does mongo expect me to use the latest modified version record???, the URL is different and so is the ID)
[ { _id: 2,
pkey: '6fea271282eb01467020ce70b5775319',
name: 'Event name 01',
owner: 'Test Owner',
device: 'Device X',
description: 'I have no idea what\'s happening',
__v: 0,
url: '/api/events/2',
modified: '2016-03-23T07:31:18.529Z',
created: '2016-03-23T07:31:18.470Z' },
{ _id: 1,
pkey: '6fea271282eb01467020ce70b5775319',
name: 'Event name 01',
owner: 'Test Owner',
device: 'Device X',
description: 'I have no idea what\'s happening',
__v: 0,
url: '/api/events/1',
modified: '2016-03-23T07:31:18.470Z',
created: '2016-03-23T07:31:18.470Z' }
]
I had assumed that unique: true on the field definition told mongo db that this what you wanted and mongo enforced that for you at save, or maybe I just misunderstood something...
In SQL terms you create a key that can be used in URL lookup but you can build a unique compound index, to prevent duplicate inserts. I need to be able to define what fields in an event make the record unique because on a form data POST the submitter of a form does not have the next available _id value, but use the _id (done by "mongoose-auto-increment") so that the URL's use from other parts of the app are clean, like
/events/1
and not a complete mess of compound values, like
/events/Event%20name%2001%5fDevice%20X%5fTest%20Owner
I'm just about to start coding up the so for now I just wrote a simple test against this single string, but the real schema has a few more fields and will use a combination of them for uniqueness, I really want to get the initial test working before I start adding more tests, more fields and more code.
Is there something that I should be doing to ensure that the second record does not actually get inserted ?

It seems that you have done unique indexing(at schema level) after inserting some records in db.
please follow below steps to avoiding duplicates -
1) drop your db:
$ mongo
> use <db-name>;
> db.dropDatabase();
2) Now do indexing at schema level or db level
var EventSchema = new mongoose.Schema({
pkey: { type: String, unique: true },
device: { type: String, required: true },
name: { type: String, required: true },
owner: { type: String, required: true },
description: { type: String, required: true },
});
It will avoid duplicate record insertion with same pKey value.
and for ensuring the index, use command db.db_name.getIndexes().
I hope it helps.
thank you

OK it looks like it has something to do with the index not having time to update before the second insert is posted (as there is only 9ms between them in my test suite).
need to do something about inserts waiting for "index"
needs to be API side as not all users of the API are web applications
I also found some other SO articles about constraints:
mongoose unique: true not work
Unique index not working with Mongoose / MongoDB
MongoDB/Mongoose unique constraint on Date field

on mongoose.connect add {useCreateIndex: true}
It should look like this
mongoose.connect(uri, {
useNewUrlParser: true,
useUnifiedTopology: true,
useCreateIndex: true
})

add:
EventSchema.index({ pkey: 1 }, { unique: true });

// Rebuild all indexes
await User.syncIndexes();
worked for me.
from https://masteringjs.io/tutorials/mongoose/unique

Meteor : Iterate through array of Objects inside an Object

I'm currently trying to iterate through an array of Objects inside an Object.
I have my Collection "Proposals", and this is the corresponding Schema :
Schemas.ProposalsSchema = new SimpleSchema({
'content': {
type: String,
max: 140
},
'parties': {
type: [Object],
autoform : {
type: "select-multiple"
}
},
'parties.$._id': {
type: Object,
optional: true
},
'parties.$._id._str': {
type: String
},
'parties.$.name': {
type: String
}
});
I would like to iterate through the array of parties inside one of my template. I tried this :
{{#each proposals}}
<p>{{content}}</p>
<p>{{#each parties}} {{this.name}} {{/each}}</p>
{{/each}}
The content is displayed, but not the name of the different parties. Here's my template helper :
Template.proposalsIndex.helpers({
proposals: () => Proposals.find().fetch()
});
Do you know what do i do wrong?
Thank you in advance.

The code you posted looks ok.
Things you need to check are:
Is the "parties" field populated in a database? (you can run Proposals.find().fetch() in a meteor shell to check it).
If not, find out why it is not populated.
Is the "parties" field published to client? (you can run Proposals.find().fetch() in a browser console and see the results).
If not, check your publication.