graphene fails on null field argument

[yeedle]

• What is the current behavior? It breaks when a literal null value is provided to a nullable field argument

from graphene import ObjectType, String, Schema, Argument

class Query(ObjectType):
  hello = String(name=Argument(String, required=False, default_value=None))

  def resolve_hello(root, info, name=None):
    return f'Hello {name}!'

schema = Schema(query=Query)

query_with_argument = 'query { hello(name: null) }'
result = schema.execute(query_with_argument)
print(result)

output:

{'errors': [{'message': 'Syntax Error GraphQL (1:21) Unexpected Name "null"\n\n1: query { hello(name: null) }\n                       ^\n', 'locations': [{'line': 1, 'column': 21}]}]}

Check out the repl.it repro.

• What is the expected behavior?

According to the spec query { field(arg: null) } and query { field } are both valid. The expected behavior would be for the above to output:

{'data': {'hello': 'Hello None!'}}

• What is the motivation / use case for changing the behavior? I have a queries (and fragments) that get reused in multiple places in the codebase. Some places require the use of optional arguments (like filters), and some don't. rather than defining two separate queries, I would like to be able to define a variable (e.g. query Foo($arg: Boolean = null) { filed(arg: $arg) } or equivalently query Foo($arg: Boolean) { field: $arg } and pass in {"arg": null} whenever I want to avoid the optional argument. This gets particularly cumbersome if there are multiple optional arguements and currently I need to define multiple queries that are exactly equivalent but for one optional argument i.

• Please tell us about your environment:

  • Version: graphene 2.1.9
  • Platform: python3.8

[jkimbo]

@yeedle v3 of graphene supports using null literals. There is a beta that you can try.

[NwawelAIroume]

exp

• What is the current behavior? It breaks when a literal null value is provided to a nullable field argument

from graphene import ObjectType, String, Schema, Argument

class Query(ObjectType):
  hello = String(name=Argument(String, required=False, default_value=None))

  def resolve_hello(root, info, name=None):
    return f'Hello {name}!'

schema = Schema(query=Query)

query_with_argument = 'query { hello(name: null) }'
result = schema.execute(query_with_argument)
print(result)

output:

{'errors': [{'message': 'Syntax Error GraphQL (1:21) Unexpected Name "null"\n\n1: query { hello(name: null) }\n                       ^\n', 'locations': [{'line': 1, 'column': 21}]}]}

Check out the repl.it repro.

• What is the expected behavior?

According to the spec query { field(arg: null) } and query { field } are both valid. The expected behavior would be for the above to output:

{'data': {'hello': 'Hello None!'}}

• What is the motivation / use case for changing the behavior? I have a queries (and fragments) that get reused in multiple places in the codebase. Some places require the use of optional arguments (like filters), and some don't. rather than defining two separate queries, I would like to be able to define a variable (e.g. query Foo($arg: Boolean = null) { filed(arg: $arg) } or equivalently query Foo($arg: Boolean) { field: $arg } and pass in {"arg": null} whenever I want to avoid the optional argument. This gets particularly cumbersome if there are multiple optional arguements and currently I need to define multiple queries that are exactly equivalent but for one optional argument i.

• Please tell us about your environment:

  • Version: graphene 2.1.9
  • Platform: python3.8

Experienced the same issue. to make it work I used to send NULL

[erikwrede]

@NwawelAIroume are you on 3.x already?