This article talks about how to return JSON in Python Graphene resolver without backslashes and quotation marks
Graphene is very stable and is probably the best library for creating GraphQL endpoints in Python. While working with Graphene, I came across an issue where JSONFields were always returned with quotation marks and backslashes —JSONString.
This article aims to address this issue using GenericScalar, which is currently an undocumented type in the current version of Graphene documentation.
This can be easily solved by overriding your meta field type in your DjangoObjectType to GenericScalar such as below.
Detailed Example with Code
In this section, I am going to run through a few snippets of codes for creating a simple mutation and query that we can work with.
Simple database model for demonstration.
Creating a DjangoObjectType for our Person object.
Let’s add some basic filters to our code while we are at it.
For simplicity’s sake, we will only need a single createPerson mutation for this example. We are going to pass in metadata as a dictionary/JSON data input for our mutation.
Finally, we will stitch everything together inside schema.py and we are ready to try things out!
Trying out the mutation
Let’s create a Person object using our newly created CreatePerson mutation at your /graphql endpoint using the built-in GraphiQL IDE or any API client of your choice (Postman, Insomnia REST Client, etc.)
As you can see in the meta field below, it’s returned as a JSONString which is not what we wanted. Things could get uglier especially when you’re dealing with a large JSON object.
The issue was apparently caused by the fact that JSONFields are by default treated as JSONString in Graphene.
However, this can simply be fixed by applying GenericScalar to types.py such as below.