I would like to use a typescript interface for an update mutation:
export interface UpdateDescription {
title: string;
publishedFrom: date | null;
}
So if null is passed as value of publishedFrom, the original date should be removed on the server. If the key would be optional and publishedFrom is not provided, but in the model there already is set a value, it would be removed as well. This is not an option! Is there is possibility to write a mutation like:
mutation UpdateExample($id: ID!, $title: String!, $publishedFrom: ISO8601DateTime!) {
updateExample(input: {id: $id, title: $title, publishedFrom: $publishedFrom}) {
errors
}
}
and make publishedFrom required but nullable?
Related
I am trying to trigger a mutation in the aws console. I have linked my resolver function to a None type data source.
However, when I define my mutation with an input type as a parameter, the error " Error Cannot return null for non-nullable type: 'String' within parent MyModelType' (/createMyModelType/id)." occurs. Everything is fine though if I replace the input type with key word arguments.
I am certain it has to do with my resolver mapping template.
Just if you're wondering why I am using a None type, I want to be able to trigger a subscription without making real database changes or mutations.
I am not sure how to make it work with input types. Here is my code for the template:
{
"version": "2017-02-28",
"payload": $util.toJson($context.args)
}
My Schema:
input CreateMyModelType5Input {
title: String
}
type Mutation {
createMyModelType5(input: CreateMyModelType5Input!): MyModelType5
}
type MyModelType5 {
id: ID!
title: String
}
type Subscription {
onCreateMyModelType5(id: ID, title: String): MyModelType5
#aws_subscribe(mutations: ["createMyModelType5"])
}
Query I am trying to run:
mutation createMyModelType($createmymodeltypeinput: CreateMyModelTypeInput!) {
createMyModelType(input: $createmymodeltypeinput) {
id
title
}
}
Query Variables for the mutation query
{
"createmymodeltype5input": {
"title": "Hello, world!"
}
}
So I have been working on passing my arguments in the graphql mutation and using the input type seemed the only straight forward way around.
However, I have been able to do it with this way:
mutation = """mutation CreateMyModelType($id: String!, $title: String!){
createMyModelType(id: $id, title: $title){
id
title
}
}
"""
input_params = {
"id": "34",
"title": "2009-04-12"
}
response = app_sync.createMyModelType(mutation, input_params)
this can be a good guide
Apollo client's codegen adds | null in the generated types, and I don't understand why they are there and how to get rid of them.
I see no reason why the API would return an array of null, so I don't want to check in my code weather the oject is null or not everytime.
Offending generated types from apollo codegen:
export interface MusicGenres_musicGenres {
name: string;
}
export interface MusicGenres {
musicGenres: (MusicGenres_musicGenres | null)[];
^^^^^^
WHY ?
}
My Graphql Schema:
type Query {
musicGenres: [MusicGenre]!
}
type MusicGenre {
id: ID!
name: String!
}
Query in my TypeScript code from which are generated the types:
gql`
query MusicGenres {
musicGenres { name }
}
`
In your schema, you have the following field definition:
musicGenres: [MusicGenre]!
This means that while musicGenres will be a list and will itself never be null, any item in the list could be null. If you want to indicate that all items in the list are also non-nullable, your field definition should instead be:
musicGenres: [MusicGenre!]!
See this post for an extended explanation.
I want to bulk update list of entries with graphQL mutation in faunaDB.
The input data is list of coronavirus cases from external source. It will be updated frequently. The mutation should update existing entries if the entry name is present in collectio and create new ones if not present.
Current GRAPHQL MUTATION
mutation UpdateList($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 have an operation and I want to get a list containing its variables and types.
Eg. given the operation
query getResource($id: ID!, $title: String) {
resource(id: $id, title: $title) {
id
title
content
}
}
I want to get something like this
[{type: "ID", required: true, name: "id"}, {type: "String", required: false, name: "title"}]
Is this easily attainable?
Edit: I guess what I want to do is to go from a VariableDefinitionNode to an object containing all the information I want, such as type, defaultValue, required, name.
You should be able to implement this if you change your schema (assuming you can generate this data on the server into this shape)
type Query {
resource ($id: ID!, $title: String): [Variable]
}
type Variable {
type: String!
required: Boolean!
name: String!
...
}
This is a very generalised syntax however, returning an array of values like that. If the structure of your resources is known, you would be better off defining that and removing the name parameter as it becomes redundant. (I'm thinking about lookups inside your client-side application)
type Query {
resource ($id: ID!, $title: String): Resource
}
type Resource {
id: Variable!
title: Variable
content: Variable
}
type Variable {
type: String!
required: Boolean!
...
}
i have an api for sign up which returns error of string or null,
error: 'Email already use' or error: null
how do i construct it in schema? what i have now is this:
const typeDefs = gql`
type Mutation {
signUp(email: String, password: String): String
}
`;
since typeof null is object, how can i make it like this in graphql?
signUp(email: String, password: String): String || Object
Help?
GraphQL has a standard syntax for returning error values and your schema does not directly need to account for this.
In your schema I would “unconditionally” return whatever type you’d normally expect to return:
type UserAccount { ... }
type Query {
me: UserAccount # or null if not signed in
}
type Mutation {
signUp(email: String!, password: String!): UserAccount!
}
If it’s unsuccessful, you will get back a null field value (even though the schema in theory claims it shouldn’t) and an error.
{
"errors": [
{
"message": "It didn’t work",
"locations": [ { "line": 2, "column": 3 } ],
"path": [ "signUp" ]
}
]
}
In GraphQL you can define what field can be null and what can't.
Take a look at the docs:
https://graphql.org/learn/schema/#object-types-and-fields
String is one of the built-in scalar types - these are types that
resolve to a single scalar object, and can't have sub-selections in
the query. We'll go over scalar types more later.
String! means that the field is non-nullable, meaning that the GraphQL service promises
to always give you a value when you query this field. In the type
language, we'll represent those with an exclamation mark.
So in case of your schema String is absolutely fine. It can be null
type Mutation {
signUp(email: String, password: String): String
}