Related
Let's say we have :
const mealSchema = Schema({
_id: Schema.Types.ObjectId,
title: { type: string, required: true },
sauce: { type: string }
});
How can we make sauce mandatory if title === "Pasta" ?
The validation needs to work on update too.
I know that a workaround would be
Find
update manually
Then save
But the risk is that if I add a new attribute (let's say "price"), I forget to update it manually too in the workaround.
Document validators
Mongoose has several built-in validators.
All SchemaTypes have the built-in required validator. The required validator uses the SchemaType's checkRequired() function to determine if the value satisfies the required validator.
Numbers have min and max validators.
Strings have enum, match, minlength, and maxlength validators.
For your case you could do something like this
const mealSchema = Schema({
_id: Schema.Types.ObjectId,
title: { type: string, required: true },
sauce: {
type: string,
required: function() {
return this.title === "pasta"? true:false ;
}
}
});
If the built-in validators aren't enough, you can define custom validators to suit your needs.
Custom validation is declared by passing a validation function. You can find detailed instructions on how to do this in the SchemaType#validate().
Update Validators
this refers to the document being validated when using document validation. However, when running update validators, the document being updated may not be in the server's memory, so by default the value of this is not defined. So, What's the solution?
The context option lets you set the value of this in update validators to the underlying query.
In your case, we can do something like this:
const mealSchema = Schema({
_id: Schema.Types.ObjectId,
title: { type: string, required: true },
sauce: { type: string, required: true }
});
mealSchema.path('sauce').validate(function(value) {
// When running update validators with
// the `context` option set to 'query',
// `this` refers to the query object.
if (this.getUpdate().$set.title==="pasta") {
return true
}else{
return false;
}
});
const meal = db.model('Meal', mealSchema);
const update = { title:'pasta', sauce:false};
// Note the context option
const opts = { runValidators: true, context: 'query' };
meal.updateOne({}, update, opts, function(error) { assert.ok(error.errors['title']); });
Not sure if this answers your question. Hope this adds some value to your final solution.
Haven't tested it, pls suggest an edit if this solution needs an upgrade.
Hope this helps.
I'm currently trying GraphQL with NodeJS and I don't know, why this error occurs with the following query:
{
library{
name,
user {
name
email
}
}
}
I am not sure if the type of my resolveLibrary is right, because at any example I had a look at they used new GraphQL.GraphQLList(), but in my case I really want to return a single user object, not an array of users.
My code:
const GraphQL = require('graphql');
const DB = require('../database/db');
const user = require('./user').type;
const library = new GraphQL.GraphQLObjectType({
name: 'library',
description: `This represents a user's library`,
fields: () => {
return {
name: {
type: GraphQL.GraphQLString,
resolve(library) {
return library.name;
}
},
user: {
type: user,
resolve(library) {
console.log(library.user);
return library.user
}
}
}
}
});
const resolveLibrary = {
type: library,
resolve(root) {
return {
name: 'My fancy library',
user: {
name: 'User name',
email: {
email: 'test#123.de'
}
}
}
}
}
module.exports = resolveLibrary;
Error:
Error: Expected Iterable, but did not find one for field library.user.
So my library schema provides a user field which returns the right data (the console.log is called).
I ran into this problem as well. It appears that what you're returning from your resolver doesn't match the return type in your schema.
Specifically for the error message Expected Iterable, but did not find one for field library.user., your schema expects an array(Iterable) but you aren't returning an array in your resolver
I had this in my schema.js:
login(email: String, password: String): [SuccessfulLogin]
I changed that to:
login(email: String, password: String): SuccessfulLogin
Notice the square brackets around "SuccessfulLogin". It's up to you whether you want to update the resolver return type or update the schema's expectations
I guess your user is an instance of GraphQLList that is why the field user is expecting to resolve to an iterable object.
I had the same problem. I was using find instead filter.
I ran into the same issue but i was using GraphQL with Go.
Solution:
I mentioned the return type to be a list( or you can say an array), but my resolver function was returning an interface and not a list of interfaces.
Before it was =>
Type: graphql.NewList(graphqll.UniversalType)
Later i changed it to =>
Type: graphqll.UniversalType
graphqll.UniversalType : 'graphqll' is the name of my user-defined package and 'UniversalType' is the GraphQL object i have created.
The previous structure of graphql object was :
var GetAllEmpDet = &graphql.Field{
Type: graphql.NewList(graphqll.UniversalType),
Resolve: func(params graphql.ResolveParams) (interface{}, error) {
...
...
// Your resolver code goes here, how you handle.
...
return models.Universal, nil // models.Universal is struct and not list of struct so it gave that error.
},
}
It worked when i changed this to:
var GetAllEmpDet = &graphql.Field{
Type: graphqll.UniversalType,
Resolve: func(params graphql.ResolveParams) (interface{}, error) {
...
...
// Your resolver code goes here, how you handle.
...
return models.Universal, nil // models.Universal is struct and not list of struct so it gave that error.
},
}
It's usually a simple mistake. Caused by declaring in the schema a List instead of a Field. The reverse will happen if you interchange. An example from Django-graphene. Switch from this:
my_query_name = graphene.List(MyModelType, id=graphene.Int())
to this:
my_query_name = graphene.Field(MyModelType, id=graphene.Int())
In my case it was related to django-graphene I didn't have a resolve method defined.
class SomeNode(DjangoObjectType):
things = graphene.List(ThingNode)
def resolve_things(self, info, **kwargs):
return self.things.all()
For me, it was a simple fix.
items: {
type: new GraphQLList(VideoType),<-- error
resolve(parentValue, args) {
const url = 'www'
return axios.get(url)
.then(res => res.data);
}
}
and change it to
items: {
type: VideoType,
resolve(parentValue, args) {
const url = 'www'
return axios.get(url)
.then(res => res.data);
}
}
I faced the same issue. For me, it was an issue with Mongo DB model.js file.
GraphQL kept throwing that error because my model was saving the field as an object whereas graphQL was returning it as an array.
The code that caused the error was this.
tableHeaders: {
text: {
type: String,
required: false,
},
align: {
type: String,
required: false,
},
sortable: {
type: Boolean,
required: false,
},
value: {
type: String,
required: false,
},
},
It was corrected to the following.
tableHeaders: [
{
text: {
type: String,
required: false,
},
align: {
type: String,
required: false,
},
sortable: {
type: Boolean,
required: false,
},
value: {
type: String,
required: false,
},
},
],
Changing type from object to array fixed it.
i had the same issue i was using findOne and that seems like the issue that didnt worked. i changed to find and it worked
#Query(()=> [Post])
async getSinglePost(
#Arg('post_id') id: string,
){
/*
const post = await getConnection().getRepository(Post).findOne({uuid:postuid})
console.log(post);
return post
*/
const post = Post.find({uuid:id})
return post
}
This simply results due to the import error
earlier code
const books =require('./data')
// Resolvers define the technique for fetching the types defined in the
// schema. This resolver retrieves books from the "books" array above.
const resolvers = {
Query: {
books(){
return books;
},
},
}
module.exports = { resolvers };
just replace the import statement with
const {books} =require('./data')
as you had ex
I wanna store unique values of any type, whether primitive values or object references. is possible? For example:
const activity = mongoose.Schema({
participants : {
type: Set, // <-- is possible?
required: true,
},
// ...
}
No, as of now it supports following data types in the latest version[5.6.3].
String,
Number,
Date,
Buffer,
Boolean,
Mixed,
ObjectId,
Array,
Decimal128,
Map
For more info on mongoose schema, please refer here
For data types supported by mongoDB, refer here
You can also use the $addToSet operator while updating that field.
For example:
const likeBook = async (req, res) => {
const {id: bookID} = req.params
const authorId = req.user.userId
const book = await Book.findByIdAndUpdate({_id: bookID}, {
$addToSet: {
like : authorId
}
})
if (!book) {
return new NotFoundError(`No Book with id: ${bookID}`)
}
await book.save()
res.status(StatusCodes.OK).json({book})
}
This will only add authorId to like array of Book if that Id doesn't exist.
You can use a setter to create a set-like array:
const activity = mongoose.Schema({
participants : {
type: Schema.Types.Mixed, // Array would probably also work
required: true,
set: toSet
},
// ...
}
function toSet(a) {
return [...new Set(a)];
}
I'm currently trying GraphQL with NodeJS and I don't know, why this error occurs with the following query:
{
library{
name,
user {
name
email
}
}
}
I am not sure if the type of my resolveLibrary is right, because at any example I had a look at they used new GraphQL.GraphQLList(), but in my case I really want to return a single user object, not an array of users.
My code:
const GraphQL = require('graphql');
const DB = require('../database/db');
const user = require('./user').type;
const library = new GraphQL.GraphQLObjectType({
name: 'library',
description: `This represents a user's library`,
fields: () => {
return {
name: {
type: GraphQL.GraphQLString,
resolve(library) {
return library.name;
}
},
user: {
type: user,
resolve(library) {
console.log(library.user);
return library.user
}
}
}
}
});
const resolveLibrary = {
type: library,
resolve(root) {
return {
name: 'My fancy library',
user: {
name: 'User name',
email: {
email: 'test#123.de'
}
}
}
}
}
module.exports = resolveLibrary;
Error:
Error: Expected Iterable, but did not find one for field library.user.
So my library schema provides a user field which returns the right data (the console.log is called).
I ran into this problem as well. It appears that what you're returning from your resolver doesn't match the return type in your schema.
Specifically for the error message Expected Iterable, but did not find one for field library.user., your schema expects an array(Iterable) but you aren't returning an array in your resolver
I had this in my schema.js:
login(email: String, password: String): [SuccessfulLogin]
I changed that to:
login(email: String, password: String): SuccessfulLogin
Notice the square brackets around "SuccessfulLogin". It's up to you whether you want to update the resolver return type or update the schema's expectations
I guess your user is an instance of GraphQLList that is why the field user is expecting to resolve to an iterable object.
I had the same problem. I was using find instead filter.
I ran into the same issue but i was using GraphQL with Go.
Solution:
I mentioned the return type to be a list( or you can say an array), but my resolver function was returning an interface and not a list of interfaces.
Before it was =>
Type: graphql.NewList(graphqll.UniversalType)
Later i changed it to =>
Type: graphqll.UniversalType
graphqll.UniversalType : 'graphqll' is the name of my user-defined package and 'UniversalType' is the GraphQL object i have created.
The previous structure of graphql object was :
var GetAllEmpDet = &graphql.Field{
Type: graphql.NewList(graphqll.UniversalType),
Resolve: func(params graphql.ResolveParams) (interface{}, error) {
...
...
// Your resolver code goes here, how you handle.
...
return models.Universal, nil // models.Universal is struct and not list of struct so it gave that error.
},
}
It worked when i changed this to:
var GetAllEmpDet = &graphql.Field{
Type: graphqll.UniversalType,
Resolve: func(params graphql.ResolveParams) (interface{}, error) {
...
...
// Your resolver code goes here, how you handle.
...
return models.Universal, nil // models.Universal is struct and not list of struct so it gave that error.
},
}
It's usually a simple mistake. Caused by declaring in the schema a List instead of a Field. The reverse will happen if you interchange. An example from Django-graphene. Switch from this:
my_query_name = graphene.List(MyModelType, id=graphene.Int())
to this:
my_query_name = graphene.Field(MyModelType, id=graphene.Int())
In my case it was related to django-graphene I didn't have a resolve method defined.
class SomeNode(DjangoObjectType):
things = graphene.List(ThingNode)
def resolve_things(self, info, **kwargs):
return self.things.all()
For me, it was a simple fix.
items: {
type: new GraphQLList(VideoType),<-- error
resolve(parentValue, args) {
const url = 'www'
return axios.get(url)
.then(res => res.data);
}
}
and change it to
items: {
type: VideoType,
resolve(parentValue, args) {
const url = 'www'
return axios.get(url)
.then(res => res.data);
}
}
I faced the same issue. For me, it was an issue with Mongo DB model.js file.
GraphQL kept throwing that error because my model was saving the field as an object whereas graphQL was returning it as an array.
The code that caused the error was this.
tableHeaders: {
text: {
type: String,
required: false,
},
align: {
type: String,
required: false,
},
sortable: {
type: Boolean,
required: false,
},
value: {
type: String,
required: false,
},
},
It was corrected to the following.
tableHeaders: [
{
text: {
type: String,
required: false,
},
align: {
type: String,
required: false,
},
sortable: {
type: Boolean,
required: false,
},
value: {
type: String,
required: false,
},
},
],
Changing type from object to array fixed it.
i had the same issue i was using findOne and that seems like the issue that didnt worked. i changed to find and it worked
#Query(()=> [Post])
async getSinglePost(
#Arg('post_id') id: string,
){
/*
const post = await getConnection().getRepository(Post).findOne({uuid:postuid})
console.log(post);
return post
*/
const post = Post.find({uuid:id})
return post
}
This simply results due to the import error
earlier code
const books =require('./data')
// Resolvers define the technique for fetching the types defined in the
// schema. This resolver retrieves books from the "books" array above.
const resolvers = {
Query: {
books(){
return books;
},
},
}
module.exports = { resolvers };
just replace the import statement with
const {books} =require('./data')
as you had ex
my schema in node js
var itemSchema = new mongoose.Schema({
name: { type: String, required: true },
value: { type: String }
});
while doing find, the following result comes,
Item.find().exec(callback); gives result
[{"one":1},{"two":2},{"three":1},{"four":1}]
but i want the result like this,
[{"one":1,"two":2,"three":3,"four":4}]
Is there only way iterate and form the result ?
Please suggest me!