I have this JSON document:
{
userId: xx,
followedAuthors: [
{ authorId: abc, timestamp: 123 },
{ authorId: xyz, timestamp: 456 },
]
}
When a user want to follow an author I would like to write a query that check if that author is already followed, checking the id, and if it's not append the new followed author to the array.
Right now I create everytime a new entry.
This is my query:
r.table('users')
.get(userId)
.replace(user => {
return user.merge({
followedTopics: user('followedTopics')
.default([])
.setInsert({ topic: topic, timestamp: now }),
})
})
The best way to implement this is to use contains (using a predicate function), branch, and append.
Related
For the following query, in some objects in the results array, some of the requested fields might not be present in the response (for example photo or address), which causes the data of my useQuery to be undefined (without any error or warning).
people(xyz: { q: $q, offset: $offset, rows: $rows }) {
results {
uri <--- this is a field of type ID!
name
photo
address {
city
country
}
}
}
My fix is to specifically check if the field exists in the incoming data and provide a fallback value, i.e.: pass a type policy for Person to be {keyFields: false} and do this in the merge function:
newItem = {...item};
newItem.photo = item.photo ?? null;
newItem.address = item.address ?? {city: "", country: ""};
Is the reason for having to do this that there's no id field in the Person type (instead, uri is of type ID!)?
Can I handle this in a better way?
Found a better way on Apollo GraphQL's GitHub.
I'd still appreciate a solution where I don't have to go over each type's nullable field in turn, if there is one.
function nullable() {
// Create a generic field policy that allows any field to be null by default:
return {
read(existing = null) {
return existing;
},
};
}
new InMemoryCache({
typePolicies: {
Person: {
fields: {
photo: nullable(),
address: nullable(),
},
},
Address: { // If there's the case of either city or country missing
fields: {
city: nullable(),
country: nullable(),
}
}
},
})
i want to create a new graphql api and i have an issue that i am struggling to fix.
the code is open source and can be found at: https://github.com/glitr-io/glitr-api
i want to create a mutation to create a record with relations... it seems the record is created correctly with all the expected relations, (when checking directly into the database), but the value returned by the create<YourTableName> method, is missing all the relations.
... so so i get an error on the api because "Cannot return null for non-nullable field Meme.author.". i am unable to figure out what could be wrong in my code.
the resolver looks like the following:
...
const newMeme = await ctx.prisma.createMeme({
author: {
connect: { id: userId },
},
memeItems: {
create: memeItems.map(({
type,
meta,
value,
style,
tags = []
}) => ({
type,
meta,
value,
style,
tags: {
create: tags.map(({ name = '' }) => (
{
name
}
))
}
}))
},
tags: {
create: tags.map(({ name = '' }) => (
{
name
}
))
}
});
console.log('newMeme', newMeme);
...
that value of newMeme in the console.log here (which what is returned in this resolver) is:
newMeme {
id: 'ck351j0f9pqa90919f52fx67w',
createdAt: '2019-11-18T23:08:46.437Z',
updatedAt: '2019-11-18T23:08:46.437Z',
}
where those fields returned are the auto-generated fields. so i get an error for a following mutation because i tried to get the author:
mutation{
meme(
memeItems: [{
type: TEXT
meta: "test1-meta"
value: "test1-value"
style: "test1-style"
}, {
type: TEXT
meta: "test2-meta"
value: "test2-value"
style: "test2-style"
}]
) {
id,
author {
displayName
}
}
}
can anyone see what issue could be causing this?
(as previously mentioned... the record is created successfully with all relationships as expected when checking directly into the database).
As described in the prisma docs the promise of the Prisma client functions to write data, e.g for the createMeme function, only returns the scalar fields of the object:
When creating new records in the database, the create-method takes one input object which wraps all the scalar fields of the record to be
created. It also provides a way to create relational data for the
model, this can be supplied using nested object writes.
Each method call returns a Promise for an object that contains all the
scalar fields of the model that was just created.
See: https://www.prisma.io/docs/prisma-client/basic-data-access/writing-data-JAVASCRIPT-rsc6/#creating-records
To also return the relations of the object you need to read the object again using an info fragment or the fluent api, see: https://www.prisma.io/docs/prisma-client/basic-data-access/reading-data-JAVASCRIPT-rsc2/#relations
I have the following query:
const getPage = gql`
query Page($path: String!) {
page(path: $path) #rest(type: "Page", path: "{args.path}") {
blocks #type(name: Block) {
name
posts #type(name: Post) {
body
author
}
}
authors #type(name: Author) {
name
}
}
}
In blocks.posts.author there's only an AuthorId. The authors object is containing all the available authors.
I'd like to replace/match the AuthorId with it's corresponding object. Is it possible to do this within one query?
I also wouldn't mind to have a separate query for Author only (fetch will be cached, no new request would be made), but I still don't know how would I match it through 2 queries.
Example API response
{
blocks: [
{
posts: [
{
id: 1,
title: 'My post',
author: 12,
}
]
}
],
authors: [
{
id: 12,
name: 'John Doe'
}
]
}
What I want with 1 query that author inside a post becomes the full author object.
Great question. With GraphQL, you have the power to expand any field and select the exact subfields you want from it, so if you were using GraphQL on your backend as well this would be a non-issue. There are some workarounds you can do here:
If all of the Author objects are in your Apollo cache and you have access to each Author's id, you could use ApolloClient.readFragment to access other properties, like this:
const authorId = ...; // the id of the author
const authorInfo = client.readFragment({
id: authorId,
fragment: gql`
fragment AuthorInfo on Author {
id
name
# anything else you want here
}
`,
});
Although it's worth noting that with your original query in the question, if you have all of the Author objects as a property of the query, you could just use Javascript operations to go from Author id to object.
const authorId = ...; // the id of the author
data.page.authors.find(author => author.id === authorId);
The following should work.
First, capture the author id as a variable using the #export directive. Then add a new field with some name other than author and decorate it with the #rest, using the exported variable inside the path.
So the query would look something like this:
query Page($path: String!) {
page(path: $path) #rest(type: "Page", path: "{args.path}") {
blocks #type(name: Block) {
name
posts #type(name: Post) {
body
author #export(as: "authorId")
authorFull #rest(
path: '/authors/{exportVariables.authorId}'
type: 'Author'
) {
name
}
}
}
authors #type(name: Author) {
name
}
}
}
You can use the fieldNameNormalizer option to rename the author property in the response to a field with a different name (for example, authorId). Ideally, that should still work with the above so you can avoid having a weird field name like authorFull but apollo-link-rest is a bit wonky so no promises.
When I'm making a request to my backend through a mutation like that:
mutation{
resetPasswordByToken(token:"my-token"){
id
}
}
I'm getting a response in such format:
{
"data": {
"resetPasswordByToken": {
"id": 3
}
}
}
And that wrapper object named the same as the mutation seems somewhat awkward (and at least redundant) to me. Is there a way to get rid of that wrapper to make the returning result a bit cleaner?
This is how I define the mutation now:
export const ResetPasswordByTokenMutation = {
type: UserType,
description: 'Sets a new password and sends an informing email with the password generated',
args: {
token: { type: new GraphQLNonNull(GraphQLString) },
captcha: { type: GraphQLString },
},
resolve: async (root, args, request) => {
const ip = getRequestIp(request);
const user = await Auth.resetPasswordByToken(ip, args);
return user.toJSON();
}
};
In a word: No.
resetPasswordByToken is not a "wrapper object", but simply a field you've defined in your schema that resolves to an object (in this case, a UserType). While it's common to request just one field on your mutation type at a time, it's possible to request any number of fields:
mutation {
resetPasswordByToken(token:"my-token"){
id
}
someOtherMutation {
# some fields here
}
andYetAnotherMutation {
# some other fields here
}
}
If we were to flatten the structure of the response like you suggest, we would not be able to distinguish between the data returned by one mutation from another. We likewise need to nest all of this inside data to keep our actual data separate from any returned errors (which appear in a separate errors entry).
I have two collections:
dbPosts
id: mongoose.Schema.Types.ObjectId,
title: { type: String },
content: { type: String },
excerpt: { type: String },
slug: { type: String },
author: {
id: { type: String },
fname: { type: String },
lname: { type: String },
}
dbAuthors
id: mongoose.Schema.Types.ObjectId,
fname: { type: String },
lname: { type: String },
posts: [
id: { type: String },
title: { type: String }
]
I resolve my author queries as follows:
Query: {
authors: (parent, root, args, context) => {
return dbAuthor.find({});
},
author: (root, args, context) => {
return dbAuthor.findById(args.id);
},
},
Author: {
posts: (parent) => {
if(parent.posts) {
return parent.posts;
} else {
return dbAuthor.find({'author.id': parent.id});
}
},
}
The reason I'm resolving thus is to optimize my MongoDB requests by denormalizing my relationships. Here's the objective:
If you need just a list of authors with the titles of their works, all necessary fields are right there in dbAuthors, so no need to look up dbPosts. But if you need more details on each post returned, say, excerpts or slug, you look up dbPosts for the following condition:
{'author.id': parent.id}
But the problem is, if your query looks like this:
authors(id: "3") {
fname
lname
posts {
title
excerpt
}
}
it breaks, because there's no excerpt field returned in the parent object. This problem could be easily fixed if there were some way I could determine what fields are being queried on an author's posts field and then decide if the values returned in parent would suffice. If not, I could then proceed to look up dbPosts with the author's id value. Is it possible? Because if not, it would defeat the whole purpose of denormalizing your collections, something Mongo strongly urges you to do!
It's rather denormalized - data is duplicated ;)
You're probably looking for info.fieldNodes