for a project I am trying to implement a graphql endpoint via flask in order to query a neo4j-DB using py2neo and graphene.
Within a docker container I am using python 3.9 and the follwing packages are installed:
- Flask==2.2.3
- graphene>=3.0
- py2neo==2021.2.3
- graphql-server[flask]
- graphql-core==3.1.0
My py2neo.ogm Graph-Object looks like that:
class Movie(BaseModel):
__primarykey__='title'
id = graphene.Int()
title = graphene.String()
year = graphene.Int()
persons = RelatedFrom("Person", "ACTED_IN")
def as_dict(self):
return {
'id': self.id,
'title': self.title,
'year': self.year,
}
def fetch(self):
return self.match(graph, self.title).first()
My graphene schema and query class are definied like that
class MovieSchema(graphene.ObjectType):
id = graphene.String()
title = graphene.String()
year = graphene.Int()
class Query(graphene.ObjectType):
# Hello is only used for test purposes
hello = graphene.String(description='A typical hello world')
movie = graphene.Field(lambda: MovieSchema, title=graphene.String())
def resolve_hello(self, info):
return 'World'
def resolve_movie(self, info, title):
return Movie.fetch(title=title)
schema = graphene.Schema(query=Query)
After building the services using docker-compose I am receiving the following error on start-up:
Traceback (most recent call last):
File "/usr/local/lib/python3.9/site-packages/graphql/type/definition.py", line 735, in fields
fields = resolve_thunk(self._fields)
File "/usr/local/lib/python3.9/site-packages/graphql/type/definition.py", line 293, in resolve_thunk
return thunk() if callable(thunk) else thunk
File "/usr/local/lib/python3.9/site-packages/graphene/types/schema.py", line 326, in create_fields_for_type
args[processed_arg_name] = GraphQLArgument( TypeError: __init__() got an unexpected keyword argument 'deprecation_reason'| During handling of the above exception, another exception occurred:
File "<frozen importlib._bootstrap>", line 1030, in _gcd_import
File "<frozen importlib._bootstrap>", line 1007, in _find_and_load
File "<frozen importlib._bootstrap>", line 986, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 680, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 850, in exec_module
File "<frozen importlib._bootstrap>", line 228, in _call_with_frames_removed
File "/var/www/server.py", line 11, in <module>
from src.graphql.schemas import schema
File "/var/www/src/graphql/schemas.py", line 47, in <module>
schema = graphene.Schema(query=Query)
File "/usr/local/lib/python3.9/site-packages/graphene/types/schema.py", line 440, in __init__
self.graphql_schema = GraphQLSchema(
File "/usr/local/lib/python3.9/site-packages/graphql/type/schema.py", line 205, in __init__
collect_referenced_types(query)
File "/usr/local/lib/python3.9/site-packages/graphql/type/schema.py", line 382, in collect_referenced_types
for field in named_type.fields.values():
File "/usr/local/lib/python3.9/functools.py", line 993, in __get__
val = self.func(instance)
File "/usr/local/lib/python3.9/site-packages/graphql/type/definition.py", line 737, in fields
raise TypeError(f"{self.name} fields cannot be resolved. {error}") TypeError: Query fields cannot be resolved. __init__() got an unexpected keyword argument 'deprecation_reason'
The problem is definitely caused by the title argument in this line:
movie = graphene.Field(lambda: MovieSchema, title=graphene.String())
Whenever I try to run the container without the title argument in the query class the container starts as expected and I can see the correct schema via the graphql interface.
Many thanks in advance for your help!
