Incorrect handling of URL Parameters

[TruDan]

I'm trying to call IFusionAuthAsyncClient.SearchUsersByIdsAsync(List<string> ids) but if say i give the id's a list containing:
["1a4a9247-2b9d-45d2-ae1e-4714756b5a58","5a1505df-677e-44e3-9c09-d858087eac7b"]

This results in an exception:

Newtonsoft.Json.JsonReaderException: Unexpected character encountered while parsing value: <. Path '', line 0, position 0.
   at async Task<IEnumerable<UserDto>> HeroBalancer.Repo.Stores.FusionAuth.FusionAuthUserStore.ReadByIds(Guid[] ids) in /build/src/Repo/Stores/FusionAuth/FusionAuthUserStore.cs:line 73

In FusionAuth, there is a very unhelpful error message which doesnt tell me much about the issue:
java.lang.IllegalArgumentException: Invalid character found in the request target. The valid characters are defined in RFC 7230 and RFC 3986

Eventually, i find in our Nginx-Ingress-Controller logs, the request that was actually made:

2020-06-03 11:33:32 | 10.244.1.219 - - [03/Jun/2020:09:33:32 +0000] "GET /api/user/search?ids=System.Collections.Generic.List%601[System.String] HTTP/1.1" 400 1985 "-" "-" 367 0.003 [default-fusionauth-80] [] 10.244.0.159:9011 1985 0.004 400 f6eaaa076541fc2a1d196711554fb795

Here you can see the ids parameter has been serialized incorrectly. According to the API documentation at https://fusionauth.io/docs/v1/tech/apis/users#search-for-users
this should be serialised as so:
ids=1a4a9247-2b9d-45d2-ae1e-4714756b5a58&ids=5a1505df-677e-44e3-9c09-d858087eac7b

[TruDan]

Related to this, in io.fusionauth.DefaultRESTClient "parameters" should be a List<KeyValuePair<string, string>> then you may add multiple parameters with the same Key. Otherwise you must handle this differently

[TruDan]

This is fixed in #22 - Can you merge this? It's a big roadblock for us currently, forcing us to package our own fork of this library to NuGet so we can use the changes and make progress with our feature releases

[robotdan]

PR is included in released version 1.17.1 of the client.
https://www.nuget.org/packages/FusionAuth.Client/