How to add header in Apollo GraphQL : iOS

Question

Hy I am working in a project with Apollo GraphQL method and its working fine. But now the client required for adding additional header with Apollo API's. But after adding the header the API's response return as unAuthorized.

I am adding the header as,

    let apolloAuth: ApolloClient = {
        let configuration = URLSessionConfiguration.default

        // Add additional headers as needed
        configuration.httpAdditionalHeaders = ["Authorization" : self.singleTonInstance.token]
        configuration.httpAdditionalHeaders = ["channel" : "mobile"]

        let url = URL(string: "http://xxx/graphql")!

        return ApolloClient(networkTransport: HTTPNetworkTransport(url: url, configuration: configuration))

    }()

Anyone please help me to find out how to add headers with Apollo GraphQL.

Answer 1

UPDATE: Solution for "Apollo Client v0.41.0" and "Swift 5"

I had the same issue with Apollo Client v0.41.0 and Swift 5.0 but none of the above solutions worked. Finally able to find a solution after the hours of try-out. The below solution is tested with Apollo Client v0.41.0 And Swift 5

import Foundation
import Apollo

class Network {
    static let shared = Network()
    
    private(set) lazy var apollo: ApolloClient = {

        let cache = InMemoryNormalizedCache()
        let store1 = ApolloStore(cache: cache)
        let authPayloads = ["Authorization": "Bearer <<TOKEN>>"]
        let configuration = URLSessionConfiguration.default
        configuration.httpAdditionalHeaders = authPayloads
        
        let client1 = URLSessionClient(sessionConfiguration: configuration, callbackQueue: nil)
        let provider = NetworkInterceptorProvider(client: client1, shouldInvalidateClientOnDeinit: true, store: store1)
        
        let url = URL(string: "https://<HOST NAME>/graphql")!
        
        let requestChainTransport = RequestChainNetworkTransport(interceptorProvider: provider,
                                                                 endpointURL: url)
        
        return ApolloClient(networkTransport: requestChainTransport,
                            store: store1)
    }()
}
class NetworkInterceptorProvider: DefaultInterceptorProvider {
    override func interceptors<Operation: GraphQLOperation>(for operation: Operation) -> [ApolloInterceptor] {
        var interceptors = super.interceptors(for: operation)
        interceptors.insert(CustomInterceptor(), at: 0)
        return interceptors
    }
}

class CustomInterceptor: ApolloInterceptor {
    
    func interceptAsync<Operation: GraphQLOperation>(
        chain: RequestChain,
        request: HTTPRequest<Operation>,
        response: HTTPResponse<Operation>?,
        completion: @escaping (Swift.Result<GraphQLResult<Operation.Data>, Error>) -> Void) {
        request.addHeader(name: "Authorization", value: "Bearer <<TOKEN>>")
        
        print("request :\(request)")
        print("response :\(String(describing: response))")
        
        chain.proceedAsync(request: request,
                           response: response,
                           completion: completion)
    }
}

Answer 2

NetworkInterceptorProvider: LegacyInterceptorProvider changed as a "DefaultInterceptorProvider"

class NetworkInterceptorProvider: DefaultInterceptorProvider {
override func interceptors<Operation: GraphQLOperation>(for operation: Operation) -> [ApolloInterceptor] {
    var interceptors = super.interceptors(for: operation)
    interceptors.insert(CustomInterceptor(), at: 0)
    return interceptors
}

}