private static void executePost(HttpUrl url, byte[] data) throws IOException {
        RequestBody requestBody = data == null
            ? RequestBody.create(MediaType.parse("text/plain"), "")
            : RequestBody.create(MediaType.parse("application/octet-stream"), data);
        Request request = new Request.Builder().url(url).post(requestBody).build();

        Response response = httpClient.newCall(request).execute();
        if (!response.isSuccessful()) {
            String responseBody = "";
            if (response.body() != null) {
                responseBody = response.body().string();
                response.close();
            }
            throw new SolrClientUtilsException(response.code(), "Unable to upload binary\n" + responseBody);
        }
        if (response.body() != null) {
            response.close();
        }
    }
Creates a new collection

@param hostname          the Hostname under which solr is reachable
@param port              The Port on which solr is running
@param collectionName    the name of the collection which should be created
@param configurationName the name of the configuration which should used to create the collection
                         or null if the default configuration should be used
modules/solr/src/main/java/org/testcontainers/containers/SolrClientUtils.java