GraphQL - How retrieve id of previous mutation, during query of multiple mutations - graphql

Question

i would like run multiple mutations in the same query.
In the example below, i create an order and after i create a product record, concerning previously created.
I must have 2 mutations.
First, i insert an order. In output, i retrieve among others, idorder.
Then, i insert an product. This product
mutation {
createOrder(input: {
order: {
ordername: "My order"
}
}) {
order {
idorder
ordername
}
},
createProduct(input: {
product: {
quantity: 3
idrefproduct: 25 # link to refProduct
idorder: XXXX # how can i retrieve idorder from output of createOrder above ? 🤔
}
}) {
product {
idproduct
}
}
}
Real example with SQL structure :
user(iduser, othersFields);
scenarios(idscenario, iduser, name, otherFields);
cultA(idcultA, idscenario, ...); // this table need of idscenario field
cultB(idcultB, idscenario, ...); // this table need of idscenario field
cultC(idcultC, idscenario, ...); // this table need of idscenario field
how can i retrieve idorder from output of createOrder above ? 🤔
It is possible ?
If i forgot some informations, don't hesitate.
Thanks in advance.
EDIT :
With PostGraphile, plugin "postgraphile-plugin-nested-mutations" or "custom mutations" (with PL PGSQL function)
Without PostGraphile, a resolver as the example of #xadm permits this particular nested mutation.

Answer 1

IMHO you can search for "nested mutations" - not described here, you'll easily find examples/tutorials.
Proposed DB structure (n-to-n relation):
order{orderID,lines[{orderLineID}] } >
order_line{orderLineID, productID, anount, price} >
product {productID}
... created in nested mutations (in reverse order product>order_line>order)
Product don't need orderID, but when you ask for it [in product resolver]
query product(id) {
id
orderedRecently {
orderID
date
price
}
}
... you can simply get it (or rather many - array) from orderLines and orders tables [using simple SQL query - where price will be read from orderLines]
orderedRecently resolver can get product id from parent object (usually 1st param)
Of course you can (and should) return data as order and orderLine types (to be cached separately, normalized):
query product($id: ID!) {
product(id: $id) {
id
orderedRecently {
id
date
orderLine {
id
amount
price
}
}
}
}
where type orderedRecently: [Order!] - array can be empty, not eordered yet
update
I slightly misunderstood your requirements (naming convention) ... you already have proper db structure. Mutation can be 'feeded' with complex data/input:
mutation {
createOrder(input: {
order: {
ordername: "My order"
products: [
{
quantity: 3
idrefproduct: 25
},
{
quantity: 5
idrefproduct: 28
}
]
}
}) {
order {
id
ordername
products {
id
idrefproduct
quantity
}
}
}
}
Your product is my orderLine, idrefproduct is product.
createOrder creates/inserts order and then use its id for creation of product records (order.id, idrefproduct and quantity). Resolver can return only order id or structured data (as above).