I have a GraphQL mutation that creates an item and returns the data that's created. I need to pass some of the created fields into a query. Is this possible? This is almost working but I can't figure out how to get the data between the mutation and the query:
mutation {
createToken(
input: { tokenname: "my token", tokendescription: "my valuable token" }
) {
id
randomdata
}
insert__helloworld_article(objects: [{randomdata: "Hello" , author_id: 1}]) {
returning {
id
}
}
}
So my problem is getting "randomdata" from the mutation to insert into the helloworld_article
You wouldn't be able to use the return value in the same mutation with GraphQL, however if those objects have a relationship you could do a nested insert.
Related
The intention is to query a list of users using an array of User IDs passed into a contains filter. The schema below is my attempt at solving this, but the query does not return a list of users. Even passing only a single User ID results in an empty query result. This schema is being published to AWS AppSync.
Is it possible to query a list of users using an array of User IDs in AppSync?
schema.graphql
type User #model {
id: ID!
username: String!
friends: [String]
}
type Query {
getAllFriends(filter: ModelAllFriendsFilterInput): ModelGetAllFriends
}
type ModelGetAllFriends {
items: [User]
}
input ModelAllFriendsFilterInput {
id: ModelAllFriendsIDInput
}
input ModelAllFriendsIDInput {
contains: [ID]
}
GraphQL Query:
query MyQuery {
getAllFriends(filter: {id: {contains: "VALID-USER-ID-HERE"}}) {
items {
id
username
}
}
}
Query result:
{
"data": {
"getAllFriends": null
}
}
Yes, lists are valid inputs in GraphQl fields.
The "null" response indicates that (a) Appsync passed your query to the resolver, (b) your resolver returned a result without error and (c) Appsync accepted the result. If any of these were not true, Appsync would have given you an error message. In other words, I believe the problem to be your resolver returning a null result, not the schema.
By the way, in the case of a list field like contains: [ID], Appsync will accept a list or a scalar value (like your {contains: "VALID-USER-ID-HERE"} above) as valid input. If you pass a scalar value to a list field, Appsync will helpfully pass it as a list/array value ["VALID-USER-ID-HERE"] in the lambda resolver's handler function arguments.
I'm trying to create a mutation that calls a child resolver in addition to the parent resolver if an optional parameter is sent in.
I'm using AWS AppSync to sent my queries to Lambda. AppSync creates and sends an AppSyncEvent to my resolver file that looks something like this:
{
"info": {
"parentTypeName": "Mutation",
"selectionSetList": [
...
],
"selectionSetGraphQL": "...",
"fieldName": "updateUser",
"variables": {}
}
}
This event gets passed to my lambda function where, based on the fieldName and parentTypeName, I call my updateUser function.
I have the below schema
schema {
query: Query
mutation: Mutation
}
type Query {
getUser(id: ID!): User
}
type Mutation {
updateUser(name: String, email: String, bookRead: BookReadInput): User
}
type User {
name: String
email: String
booksRead: [Book]
}
type Book {
title: String
author: String
}
type BookReadInput {
title: String
author: String
}
I want that if the mutation gets passed bookRead then it will know to call a child resolver called addBook besides for the regular updateUser resolver.
I've seen various articles about implementing child resolvers but I can't figure out how they can work with lambda and the way my resolvers work.
The lambda could inspect the selectionSetList and decide what to do with the BookReadInput fields.
See https://aws.amazon.com/blogs/mobile/appsync-and-the-graphql-info-object/
You could also go with pipeline resolvers to first update the user, and then add the book.
I don't think there is a way to have it automated. You need to set it up, one way or the other.
I want to bulk update list of entries with graphQL mutation in faunaDB.
The input data is list of coronavirus cases from external source. It will be updated frequently. The mutation should update existing entries if the entry name is present in collectio and create new ones if not present.
Current GRAPHQL MUTATION
mutation UpdateList($data: ListInput!) {
updateList(id: "260351229231628818", data: $data) {
title
cities {
data {
name
infected
}
}
}
}
GRAPHQL VARIABLES
{
"data": {
"title": "COVID-19",
"cities": {
"create": [
{
"id": 22,
"name": "Warsaw",
"location": {
"create": {
"lat": 52.229832,
"lng": 21.011689
}
},
"deaths": 0,
"cured": 0,
"infected": 37,
"type": "ACTIVE",
"created_timestamp": 1583671445,
"last_modified_timestamp": 1584389018
}
]
}
}
}
SCHEMA
type cityEntry {
id: Int!
name: String!
deaths: Int!
cured: Int!
infected: Int!
type: String!
created_timestamp: Int!
last_modified_timestamp: Int!
location: LatLng!
list: List
}
type LatLng {
lat: Float!
lng: Float!
}
type List {
title: String!
cities: [cityEntry] #relation
}
type Query {
items: [cityEntry!]
allCities: [cityEntry!]
cityEntriesByDeathFlag(deaths: Int!): [cityEntry!]
cityEntriesByCuredFlag(cured: Int!): [cityEntry!]
allLists: [List!]
}
Everytime the mutation runs it creates new duplicates.
What is the best way to update the list within single mutation?
my apologies for the delay, I wasn't sure exactly what the missing information was hence why I commented first :).
The Schema
An example of a part of a schema that has arguments:
type Mutation {
register(email: String!, password: String!): Account! #resolver
login(email: String!, password: String!): String! #resolver
}
When such a schema is imported in FaunaDB there will be placeholder functions provided.
The UDF parameters
As you can see all the function does is Abort with the message that the function still has to be implemented. The implementation starts with a Lambda that takes arguments and those arguments have to match what you defined in the resolver.
Query(Lambda(['email', 'password'],
... function body ...
))
Using the arguments is done with Var, that means Var('email') or Var('password') in this case. For example, in my specific case we would use the email that was passed in to get an account by email and use the password to pass on to the Login function which will return a secret (the reason I do the select here is that the return value for a GraphQL resolver has to be a valid GraphQL result (e.g. plain JSON
Query(Lambda(['email', 'password'],
Select(
['secret'],
Login(Match(Index('accountsByEmail'), Var('email')), {
password: Var('password')
})
)
))
Calling the UDF resolver via GraphQL
Finally, how to pass parameters when calling it? That should be clear from the GraphQL playground as it will provide you with the docs and autocompletion. For example, this is what the auto-generated GraphQL docs tell me after my schema import:
Which means we can call it as follows:
mutation CallLogin {
login (
email: "<some email>"
password: "<some pword>"
)
}
Bulk updates
For bulk updates, you can also pass a list of values to the User Defined Function (UDF). Let's say we would want to group a number of accounts together in a specific team via the UI and therefore want to update multiple accounts at the same time.
The mutation in our Schema could look as follows (ID's in GraphQL are similar to Strings)
type Mutation { updateAccounts(accountRefs: [ID]): [ID]! #resolver }
We could then call the mutation by providing in the id's that we receive from FaunaDB (the string, not the Ref in case you are mixing FQL and GraphQL, if you only use GraphQL, don't worry about it).
mutation {
updateAccounts(accountRefs: ["265317328423485952", "265317336075993600"] )
}
Just like before, we will have to fill in the User Defined Function that was generated by FaunaDB. A skeleton function that just takes in the array and returns it would look like:
Query(Lambda(['arr'],
Var('arr')
))
Some people might have seen an easier syntax and would be tempted to use this:
Query(Lambda(arr => arr))
However, this currently does not work with GraphQL when passing in arrays, it's a known issue that will be fixed.
The next step is to actually loop over the array. FQL is not declarative and draws inspiration from functional languages which means you would do that just by using a 'map' or a 'foreach'
Query(Lambda(["accountArray"],
Map(Var("accountArray"),
Lambda("account", Var("account")))
))
We now loop over the list but don't do anything with it yet since we just return the account in the map's body. We will now update the account and just set a value 'teamName' on there. For that we need the Update function which takes a FaunaDB Reference. GraphQL sends us strings and not references so we need to transform these ID strings to a reference with Ref as follows:
Ref(Collection('Account'), Var("account"))
If we put it all together we can add an extra attribute to a list of accounts ids as follows:
Query(Lambda(["accountArray"],
Map(Var("accountArray"),
Lambda("account",
Do(
Update(
Ref(Collection('Account'), Var("account")),
{ data: { teamName: "Awesome live-coders" } }
),
Var("account")
)
)
)
))
At the end of the Map, we just return the ID of the account again with Var("account") in order to return something that is just plain JSON, else we would be returning FaunaDB Refs which are more than just JSON and will not be accepted by the GraphQL call.
Passing in more complex types.
Sometimes you want to pass in more complex types. Let's say we have a simple todo schema.
type Todo {
title: String!
completed: Boolean!
}
And we want to set the completed value of a list of todos with specific titles to true. We can see in the extended schema generated by FaunaDB that there is a TodoInput.
If you see that extended schema you might think, "Hey that's exactly what I need!" but you can't access it when you write your mutations since you do not have that part of the schema at creation time and therefore can't just write:
type Mutation { updateTodos(todos: [TodoInput]): Boolean! #resolver }
As it will return the following error.
However, we can just add it to the schema ourselves. Fauna will just accept that you already wrote it and not override it (make sure that you keep the required fields, else your generated 'createTodo' mutation won't work anymore).
type Todo {
title: String!
completed: Boolean!
}
input TodoInput {
title: String!
completed: Boolean!
}
type Mutation { updateTodos(todos: [TodoInput]): Boolean! #resolver }
Which means that I can now write:
mutation {
updateTodos(todos: [{title: "test", completed: true}])
}
and dive into the FQL function to do things with this input.
Or if you want to include the ID along with data you can define a new type.
input TodoUpdateInput {
id: ID!
title: String!
completed: Boolean!
}
type Mutation { updateTodos(todos: [TodoUpdateInput]): Boolean! #resolver }
Once you get the hang of it and want to learn more about FQL (that's a whole different topic) we are currently writing a series of articles along with code for which the first one appeared here: https://css-tricks.com/rethinking-twitter-as-a-serverless-app/ which is probably a good gentle introduction.
I want to do 2 creations in my GraphQL query. (I know my query structure is not correct, but it's to illustrate my question)
mutation {
affiliateCreate(company: "test mutation") {
$id: id,
affiliateUserCreate(affiliate_id: $id, name: "test name") {
id,
name
},
company
}
}
I want my first id result to be in variable who i pass to the second creation call? I'm very new to GraphQL and i was wondering if it's possible.
Is there any other way possible to do such thing? Or i must do 2 mutation call? The first with affiliateCreate and in it's fallback the second one?
Thank you
What you want to do is not supported by GraphQL. In the Graphcool APIs we approach this kind of situation with what we call nested mutations. I've also heard it being referred to as complex mutations.
A nested create mutation is characterized by a nested input object argument. If you add an input object author to the affiliateCreate mutation, you could use it like that:
mutation createAffiliateAndUser {
affiliateCreate(
company: "test company"
author: {
name: "test user"
}
) {
id
}
}
This would create an affiliate, a user and then link the two together. Similarily, if you add an input object affiliates to the userCreate mutation, it could look like this:
mutation createUserAndAffiliates {
userCreate(
name: "test user"
affiliates: [{
company: "first company"
}, {
company: "second company"
}]
) {
id
}
}
I'm trying to have a representation of nodes on GraphQL more akin to what jsonapi would be like http://jsonapi.org/
What I mean is if we take one of the examples on GraphQL
{
hero {
name
# Queries can have comments!
friends {
name
}
}
}
Have a representation that would be more along these lines
{
hero {
name
# Queries can have comments!
friends {
id
}
},
friends {
id, name
}
}
Is that at all possible in GraphQL
Thanks
It is possible, and there's nothing wrong with having a friends field. In GraphQL terms you can have the following part of the schema:
type User {
id: ID
name: String
firends: [User]
}
type RootQuery {
hero: User
friends(forUserId: ID!): [User]
}
And then you can query this as you like – you can ask for friends separately:
{
friends(forUserId: "12") {
id, name
}
}
But the whole idea of GraphQL is that you don't have to do multiple queries to get the information you need. If you just need a list of users – that's a reasonable query, that most people have (with arguments for pagination and so on). With that said, there's no reason to fetch a list of IDs and to send another fetch query for the data right after that.