Optional variables in the graphql API

Support
, ,
1

Hello,

I’m trying to get the mapping of an graphql endpoint to an external REST API working. The most parts work so far, only the optional variables do not work and I could not figure out why.

The test configuration for the gateway looks like this:

{
    "cache_options": {
        "cache_timeout": 10,
        "enable_cache": false,
        "cache_all_safe_requests": false,
        "enable_upstream_cache_control": false,
        "cache_by_headers": [],
        "cache_response_codes": [
            200
        ]
    },
    "enable_detailed_recording": true,
    "name": "My GraphQL API",
    "api_id": "my-graphql-api",
    "org_id": "my-org-id",
    "use_keyless": true,
    "version_data": {
        "not_versioned": false,
        "default_version": "Default",
        "versions": {
            "Default": {
                "name": "Default",
                "expires": "3000-01-02 15:04",
                "use_extended_paths": true
            }
        }
    },
    "proxy": {
        "listen_path": "/my-graphql-api/",
        "target_url": "",
        "strip_listen_path": true
    },
    "graphql": {
        "enabled": true,
        "execution_mode": "executionEngine",
        "schema": "type Post { userId: Int id: Int title: String body: String } type Comment { postId: Int id: Int name: String email: String body: String } type Album { userId: Int id: Int title: String } type Photo { albumId: Int id: Int title: String url: String thumbnailUrl: String } type Todo { userId: Int id: Int title: String completed: Boolean } type User { id: Int name: String username: String email: String address: Address phone: String website: String company: Company } type Address { street: String suite: String city: String zipcode: String geo: Geo } type Geo { lat: String lng: String } type Company { name: String catchPhrase: String bs: String } type Query { posts(userId:Int): [Post] comments(postId:Int): [Comment] albums(userId:Int): [Album] photos(albumId:Int): [Photo] todos(userId:Int): [Todo] users(id:Int): [User] }",
        "type_field_configurations": [
            {
                "type_name": "Query",
                "field_name": "posts",
                "mapping": {
                    "disabled": false,
                    "path": "",
                    "url_rewrites": [
                        {
                            "match_pattern": "/posts(\\?.*)?",
                            "rewrite_to": "/posts/{{ .arguments.userId }}$1"
                        }
                    ]
                },
                "data_source": {
                    "kind": "HTTPJSONDataSource",
                    "data_source_config": {
                        "url": "https://jsonplaceholder.typicode.com/posts",	
                        "method": "GET"
                    }
                }
            }
        ]
    }
}

The post API returns the posts like it should when the query {posts{userId}} is used.

The problem is when an optional variable is defined it does not return anything eg {posts(userId:1){userId}} and the URL is not adjusted.

What is needed that the URL gets adapted when the userId is set?

2

Hey @lexermal
I noticed 2 things with your API definition:

  • You are using the “old” way of connecting data sources. In Tyk 3.2 the Tyk API definition has changed a bit. Are you using some older version of Tyk?
  • You are trying to do a URL rewrite on the data source directly, in UDG. That will not work. You’d have to proxy your REST as you usually would, just create it as a separate API in Tyk. Do your URL rewrites on the REST API and then use that API as a data source.

I’ll prepare an example for you tomorrow, if you don’t mind waiting.