Strawchemy

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Queries ​

A mapped type plus a field on Query is all a read API needs. The field's arguments come from what you pass to strawchemy.field().

Declaring the types ​

Declare the output type and the two inputs a query field takes. UserAggregationType comes from @strawchemy.aggregate; it is declared here so the third field below resolves:

python
@strawchemy.type(User, include="all", override=True)
class UserType: ...


@strawchemy.filter(User, include="all")
class UserFilter: ...


@strawchemy.order(User, include="all")
class UserOrderBy: ...


@strawchemy.aggregate(User, include="all")
class UserAggregationType: ...

Adding the fields ​

The return annotation decides the shape, exactly as it does for mutations: a list annotation gives a list field, a single annotation gives a get-by-id field whose id argument is generated (the name comes from StrawchemyConfig.default_id_field_name, "id" unless changed).

python
@strawberry.type
class Query:
    users: list[UserType] = strawchemy.field(filter_input=UserFilter, order_by_input=UserOrderBy)
    user: UserType = strawchemy.field()
    users_aggregate: UserAggregationType = strawchemy.field(root_aggregations=True)

Each argument to strawchemy.field() adds its own piece of the field:

  • filter_input — adds a filter argument. Filtering
  • order_by_input — adds an orderBy argument. Ordering
  • pagination — adds limit and offset. Pagination
  • distinct_on — adds a distinctOn argument, which restricts results to the first row for each distinct value of the given fields. Distinct rows
  • root_aggregations — switches the field into aggregate mode. Aggregations

Building the schema ​

python
schema = strawberry.Schema(query=Query)
  • Filtering — narrow a list down with a filter argument.
  • Ordering — sort a list with an orderBy argument.
  • Pagination — page through a list with limit and offset.
  • Aggregations — count and summarize rows, per relationship or at the root.
  • Custom resolvers — write a resolver method backed by the same repository.
  • Query hooks — reach into the statement Strawchemy builds before it runs.