fix: Custom http headers and query parameters for ios (#28)

Adding support for additional query parameters in
authorization request and http headers in the authentication requests

This was already supported on android.

Note that the headers will only be sent in authentication
requests,not in the token request.

ios/HaapiModule/ConfigurationHelper.swift

@@ -32,15 +32,19 @@ class ConfigurationHelper {
                                     delegate: validateTlsCertificate ? nil : TrustAllCertsDelegate(),
                                     delegateQueue: nil)
         let boundedTokenConfiguration = BoundedTokenConfiguration()
+        let extraRequestParameters = getStringMap(data: data, configKey: "extraRequestParameters")
+        let extraHttpHeaders = getStringMap(data: data, configKey: "extraHttpHeaders")
 
         return HaapiConfiguration(name: getStringOrDefault(data: data, configKey: "configurationName", defaultString: "HaapiModule"),
                                   clientId: try getStringOrThrow(data: data, configKey: "clientId"),
                                   baseURL: try getUrlOrThrow(data: data, configKey: "baseUri"),
                                   tokenEndpointURL: try getUrlOrThrow(data: data, configKey: "tokenEndpointUri"),
                                   authorizationEndpointURL: try getUrlOrThrow(data: data, configKey: "authorizationEndpointUri"),
                                   appRedirect: getStringOrDefault(data: data, configKey: "appRedirect", defaultString: "app:start"),
-                                  httpHeadersProvider: nil,
-                                  authorizationParametersProvider: { () -> OAuthAuthorizationParameters in OAuthAuthorizationParameters(scopes: scope, acrValues: acrValues) },
+                                  httpHeadersProvider: { extraHttpHeaders },
+                                  authorizationParametersProvider: { () -> OAuthAuthorizationParameters in OAuthAuthorizationParameters(scopes: scope,
+                                                                                                                                        acrValues: acrValues,
+                                                                                                                                        extraRequestParameters: extraRequestParameters) },
                                   isAutoRedirect: true,
                                   urlSession: urlSession,
                                   tokenBoundConfiguration: boundedTokenConfiguration)
@@ -68,4 +72,15 @@ class ConfigurationHelper {
             .split(separator: " ")
             .map { String($0) }
     }
+
+    private static func getStringMap(data: Dictionary<String, Any>, configKey: String) -> Dictionary<String, String> {
+        guard let map = data[configKey] as? [String: Any] else { return [String: String]() }
+        var stringMap = [String: String]()
+        for (key, value) in map {
+            if let value = value as? String {
+                stringMap[key] = value
+            }
+        }
+        return stringMap
+    }
 }