id | title | sidebar_label |
---|---|---|
tutorial-todo-gql-mutation-input |
Mutation Inputs |
Mutation Inputs |
In this section, we continue the GraphQL example by explaining how to extend the Ent code generator using Go templates and generate input type objects for our GraphQL mutations that can be applied directly on Ent mutations.
The code for this tutorial is available under github.com/a8m/ent-graphql-example, and tagged (using Git) in each step. If you want to skip the basic setup and start with the initial version of the GraphQL server, you can clone the repository and run the program as follows:
git clone git@github.com:a8m/ent-graphql-example.git
cd ent-graphql-example
go run ./cmd/todo/
Ent supports generating mutation types. A mutation type can be accepted as an input for GraphQL mutations, and it is
handled and verified by Ent. Let's tell Ent that our GraphQL Todo
type supports create and update operations:
func (Todo) Annotations() []schema.Annotation {
return []schema.Annotation{
entgql.QueryField(),
//highlight-next-line
entgql.Mutations(entgql.MutationCreate(), entgql.MutationUpdate()),
}
}
Then, run code generation:
go generate .
You'll notice that Ent generated for you 2 types: ent.CreateTodoInput
and ent.UpdateTodoInput
.
After generating our mutation inputs, we can connect them to the GraphQL mutations:
type Mutation {
createTodo(input: CreateTodoInput!): Todo!
updateTodo(id: ID!, input: UpdateTodoInput!): Todo!
}
Running code generation we'll generate the actual mutations and the only thing left after that is to bind the resolvers to Ent.
go generate .
// CreateTodo is the resolver for the createTodo field.
func (r *mutationResolver) CreateTodo(ctx context.Context, input ent.CreateTodoInput) (*ent.Todo, error) {
return r.client.Todo.Create().SetInput(input).Save(ctx)
}
// UpdateTodo is the resolver for the updateTodo field.
func (r *mutationResolver) UpdateTodo(ctx context.Context, id int, input ent.UpdateTodoInput) (*ent.Todo, error) {
return r.client.Todo.UpdateOneID(id).SetInput(input).Save(ctx)
}
Let's start with creating 2 todo items by executing the createTodo
mutations twice.
mutation CreateTodo {
createTodo(input: {text: "Create GraphQL Example", status: IN_PROGRESS, priority: 2}) {
id
text
createdAt
priority
parent {
id
}
}
}
{
"data": {
"createTodo": {
"id": "1",
"text": "Create GraphQL Example",
"createdAt": "2021-04-19T10:49:52+03:00",
"priority": 2,
"parent": null
}
}
}
mutation CreateTodo {
createTodo(input: {text: "Create Tracing Example", status: IN_PROGRESS, priority: 2}) {
id
text
createdAt
priority
parent {
id
}
}
}
{
"data": {
"createTodo": {
"id": "2",
"text": "Create Tracing Example",
"createdAt": "2021-04-19T10:50:01+03:00",
"priority": 2,
"parent": null
}
}
}
The only thing left is to test the UpdateTodo
resolver. Let's use it to update the parent
of the 2nd todo item to 1
.
mutation UpdateTodo {
updateTodo(id: 2, input: {parentID: 1}) {
id
text
createdAt
priority
parent {
id
text
}
}
}
{
"data": {
"updateTodo": {
"id": "2",
"text": "Create Tracing Example",
"createdAt": "2021-04-19T10:50:01+03:00",
"priority": 1,
"parent": {
"id": "1",
"text": "Create GraphQL Example"
}
}
}
}