Mutations support

[simonw]

Supporting mutations for inserting / updating data is a very useful next step.

[simonw]

It would be good to be able to detect if a table has an auto-incrementing primary key - if it does, an insert can be supported by providing the non-primary-key columns. If not, then inserts will also need to include the desired primary key.

[simonw]

Graphene docs: https://docs.graphene-python.org/en/latest/types/mutations/

import graphene

class CreatePerson(graphene.Mutation):
    class Arguments:
        name = graphene.String()

    ok = graphene.Boolean()
    person = graphene.Field(lambda: Person)

    def mutate(root, info, name):
        person = Person(name=name)
        ok = True
        return CreatePerson(person=person, ok=ok)

class Person(graphene.ObjectType):
    name = graphene.String()
    age = graphene.Int()

class MyMutations(graphene.ObjectType):
    create_person = CreatePerson.Field()

# We must define a query for our schema
class Query(graphene.ObjectType):
    person = graphene.Field(Person)

schema = graphene.Schema(query=Query, mutation=MyMutations)

Then:

mutation m {
    createPerson(name:"Peter") {
        person {
            name
        }
        ok
    }
}

[simonw]

Maybe the configuration that defines these should use YAML (or JSON) strings containing the GraphQL type language.

https://graphql.org/learn/schema/

input ReviewInput {
  stars: Int!
  commentary: String
}

[simonw]

The graphql-core library (which graphene already depends on) has a parser for the GraphQL language: https://github.com/graphql-python/graphql-core/blob/master/src/graphql/language/parser.py

[simonw]

Datasette 1.0 alpha has JSON write APIs now, which could help inform the design and implementation of this:

https://docs.datasette.io/en/1.0a2/json_api.html#the-json-write-api