curl.cpp

#include "curl.h"

// Tweak for older libcurls
#ifndef CURL_HTTP_VERSION_2_0
#define CURL_HTTP_VERSION_2_0 CURL_HTTP_VERSION_1_1
#endif


std::string helpers::get_http_query(const curl_params &params)
{
    std::string result;

    for (auto &par : params) {
        if (result.length() > 0) {
            result += "&";
        }

        result += par.first + "=" + par.second;
    }

    return result;
}

static size_t string_write_wrapper(void *ptr, size_t size, size_t nmemb, std::string *str)
{
    size_t length = size * nmemb;

    std::copy((char *) ptr, (char *) ptr + length, std::back_inserter(*str));

    return length;
}

std::string helpers::curl_get(const std::string &url,
    const long port,
    const curl_params &params,
    const std::string &username,
    const std::string &passwd)
{
    std::string result;
    std::string query = get_http_query(params);
    std::string url_query = url + "?" + query;
    CURL *curl;
    CURLcode res;

    // get curl handle
    curl = curl_easy_init();
    if (curl) {
        // destination address
        curl_easy_setopt(curl, CURLOPT_URL, url_query.c_str());

        // set port
        curl_easy_setopt(curl, CURLOPT_PORT, port);

        // set writer wrapper and result string
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, string_write_wrapper);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &result);

        // Follow redirects
        curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
        // Ennable support for HTTP2
        curl_easy_setopt(curl, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_2_0);
        // We have trusted HTTPS certificate, so set validation on
        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 1L);
        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 2L);
        // Causes error on HTTP responses >= 400
        curl_easy_setopt(curl, CURLOPT_FAILONERROR, 1L);

        if (username.length() != 0 || passwd.length() != 0) {
            curl_easy_setopt(curl, CURLOPT_HTTPAUTH, CURLAUTH_BASIC);
            curl_easy_setopt(curl, CURLOPT_USERPWD, (username + ":" + passwd).c_str());
        }

        // Enable verbose for easier tracing
        // curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);

        // perform action itself
        res = curl_easy_perform(curl);

        // Always cleanup
        curl_easy_cleanup(curl);

        // Check for errors
        if (res != CURLE_OK) {
            long response_code;
            curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &response_code);
            auto error_message = "GET request failed to " + url_query + ". Error: (" + std::to_string(response_code) +
                ") " + curl_easy_strerror(res);
            throw curl_exception(error_message);
        }
    }

    return result;
}

std::string helpers::curl_post(const std::string &url,
    const long port,
    const curl_params &params,
    const std::string &username,
    const std::string &passwd)
{
    std::string result;
    std::string query = get_http_query(params);
    std::string url_query = url + "?" + query;
    CURL *curl;
    CURLcode res;

    // get curl handle
    curl = curl_easy_init();
    if (curl) {
        // destination address
        curl_easy_setopt(curl, CURLOPT_URL, url.c_str());

        // set port
        curl_easy_setopt(curl, CURLOPT_PORT, port);

        /* Now specify the POST data */
        curl_easy_setopt(curl, CURLOPT_POSTFIELDS, query.c_str());

        // set writer wrapper and result string
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, string_write_wrapper);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &result);

        // Follow redirects
        curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
        // Ennable support for HTTP2
        curl_easy_setopt(curl, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_2_0);
        // We have trusted HTTPS certificate, so set validation on
        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 1L);
        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 2L);
        // Causes error on HTTP responses >= 400
        curl_easy_setopt(curl, CURLOPT_FAILONERROR, 1L);

        if (username.length() != 0 || passwd.length() != 0) {
            curl_easy_setopt(curl, CURLOPT_HTTPAUTH, CURLAUTH_BASIC);
            curl_easy_setopt(curl, CURLOPT_USERPWD, (username + ":" + passwd).c_str());
        }

        // Enable verbose for easier tracing
        // curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);

        // perform action itself
        res = curl_easy_perform(curl);

        // Always cleanup
        curl_easy_cleanup(curl);

        // Check for errors
        if (res != CURLE_OK) {
            long response_code;
            curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &response_code);
            auto error_message = "POST request failed to " + url_query + ". Error: (" + std::to_string(response_code) +
                ") " + curl_easy_strerror(res);
            throw curl_exception(error_message);
        }
    }

    return result;
}