src/Client.php
public function post($section, $body = null, array $headers = [])
    {
        if (is_array($body)) {
            $body = array_merge($this->parameters, $body, $this->defaultParameters);

            $body = http_build_query($body);
        }

        return $this->client->post($this->getUrl($section), $headers, $body);
    }
public function post($section, $body = null, array $headers = [])
    {
        if (is_array($body)) {
            $body = array_merge($this->parameters, $body, $this->defaultParameters);

            $body = http_build_query($body);
        }

        return $this->client->post($this->getUrl($section), $headers, $body);
    }
Sends a POST request.

@param string                            $section URI section
@param string|array|StreamInterface|null $body    Body content or Http post parameters
@param array                             $headers Http headers

@throws Exception

@return ResponseInterface PSR-7 Response