public void write(String payload,
            final IAsyncHandler<InfluxException> failureHandler) {
        // Make request to influx
        IHttpClientRequest request = httpClient.request(writeUrl.toString(), HttpMethod.POST,
                result -> {
                    if (result.isError() || result.getResult().getResponseCode() < 200
                            || result.getResult().getResponseCode() > 299) {
                        failureHandler.handle(new InfluxException(result.getResult()));
                    }
                });
        // For some reason Java's URLEncoding doesn't seem to be parseable by influx?
        //request.addHeader("Content-Type", "application/x-www-form-urlencoded");
        if (token != null) {
            request.addHeader("Authorization", "Token " + token);
        }
        request.addHeader("Content-Type", "text/plain");
        request.write(payload, StandardCharsets.UTF_8.name());
        request.end();
    }
Simple write to "/write". Must be valid Influx line format.

@param payload document to write, as string (payload may be a batch).
@param failureHandler handler in case of failure
gateway/engine/influxdb/src/main/java/io/apiman/gateway/engine/influxdb/InfluxDb09Driver.java