Usage of query parameters in sub resolvers

Drivers & Stacks GraphQL & GRANDstack
1

I want to use a given GraphQL query parameter in @cypher directives that load data for a sub-type.

A simplified version of my schema:

type Query {
    find(warrantyNo: String!, locale: String!): Warranty @cypher(statement: """
        MATCH (result)-[:HAS]->(:ExternalId {externalId: $warrantyNo}) RETURN result
    """, columnName: "result")
}

type Warranty {
    locale: String! @cypher(statement: """
        return $locale AS result
        """, columnName: "result")
    title: String @cypher(statement: """
        MATCH (this)-[:HAS_VALUE]->(v:TextValue)-[t:HAS_TRANSLATION]->(:Language {isoCode: $locale}) return t.value AS result
        """, columnName: "result")
}

As you can see I want to use the $locale variale in Cypher queries that load data for the Warranty: is that supported/possible? Right now I get this error message: "Neo4jError: Expected parameter(s): locale"

The variable works for the first Cypher query, but I cannot use it the for Cypher queries required for Warranty. The locale property is just a simple test.

And thanks a lot for the great library you provide :slight_smile:

2

Hi @torsten.kuhnhenne !

From what you're trying to do, I think the best option for you is to use input arguments.

It's worth taking a look at the documentation to see what options are available to you.

Best of luck,

Michael

3

Hi @michael.webb ,

thanks for the quick response. From my point of view I am using input arguments for the first query and I want to access those arguments in the queries that are automatically triggerd for the loading of the additional data for the sub-type Warranty.

The GraphQL query is:

query ExampleQuery($warrantyNo: String!, $locale: String!) {
  
  find(warrantyNo: $warrantyNo, locale: $locale) {
    title
  }
}

Variables:

{  
  "warrantyNo": "801430101",
  "locale": "de"
}

And when the server tries to load title I end up with the error. From my point of view locale is not available a input parameter for this query.

4

Hi @torsten.kuhnhenne

You can use cypherParams in the server context to forward the query variables to the nested @cypher directives.

An example:

context: async ({ req }) => ({
    token: req.headers.authorization,
    cypherParams: {
        locale: req.body.variables.locale,
    },
}),

Note that token in my example is not required, but is commonly seen in use within the context, so I left it in for contextual knowledge.

Hope that helps!

Michael

5

Hi @michael.webb ,

it is working! Thanks a lot for your great support :-)

Kind regards,
Torsten

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