Steps to reproduce:
List the minimal actions needed to reproduce the behaviour.

1. behaviour can be reproduced with the following code snippet:

FluxClient fluxClient = FluxClientFactory.create("http://exampleurl.com/influxDB/");

        String flux = "from(bucket:\"test_bucket/hour\")\n" +
                "        |> range(start:-5m)";

        List<FluxTable> tables = fluxClient.query(flux);

Expected behavior:
Describe what you expected to happen.

The flux client should query http://exampleurl.com/influxDB/api/v2/query and return the results of the query.

Actual behavior:
Describe What actually happened.

The fluxClient returns a com.influxdb.exceptions.NotFoundException but upon debugging, we can see the response actually looks like Response{protocol=http/1.1, code=404, message=Not Found, url=http://exampleurl.com/api/v2/query}

Therefore the /InfluxDB was cut off of the baseURL.

Specifications:

• Client Version: 2.2.0
• InfluxDB Version: 1.8
• JDK Version: V8 u251
• Platform: Mac (Mojave)