Send Custom String with cURL in Qt C++ - c++

i use the cURL Library for send and login users to my application and server and use POST method in cURL. but i want to send custom and get input from user and send to the server and response but seem's error. my source below (the username and password is defined string):
curl_easy_setopt(curl, CURLOPT_POSTFIELDS, "Username=" + username + "&Password=" + password);
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, WriteCallback);
curl_easy_setopt(curl, CURLOPT_WRITEDATA, &readBuffer);
But this do not work. Only agree with this sample pattern:
curl_easy_setopt(curl, CURLOPT_POSTFIELDS, "Username=sina&Password=12781278");
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, WriteCallback);
curl_easy_setopt(curl, CURLOPT_WRITEDATA, &readBuffer);

Related

Ignore curl response body in c++

I am doing a post request using CURL in c++ and I wanted to know if theres a way to ignore the response body that gets printed to the output. This is what my code looks like currently
if (curl) {
// Set url
curl_easy_setopt(curl, CURLOPT_URL, str_url);
// Set header
list = curl_slist_append(list, header);
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, list);
// Set request type and data
curl_easy_setopt(curl, CURLOPT_POST, 1);
curl_easy_setopt(curl, CURLOPT_POSTFIELDS, body);
curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, (long)strlen(body));
res = curl_easy_perform(curl);
everything works but I keep getting the response body posted to the output and I just want to ignore it since all I need is the response code. With the command line I can make a curl request with the following curl --silent --output to ignore it but is there a way to do this in c++?

Umlauts problem when sending Json Post with VS2017 C++ using libcurl

when posting data to zendesk, all of my umlauts are saved as "?" characters.
the same post from the postmann app works fine.
i even copied the whole postman C - libcurl code, compiled and fired it up:
same result, umlauts are shown as questionsmarks.
Whats the difference between postman posting the json and visual studio posting it?
here is the code:
CURL *curl;
CURLcode res;
curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "POST");
curl_easy_setopt(curl, CURLOPT_URL, "https://xx.zendesk.com/api/v2/users/create_or_update.json");
curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
curl_easy_setopt(curl, CURLOPT_DEFAULT_PROTOCOL, "https");
struct curl_slist *headers = NULL;
headers = curl_slist_append(headers, "id: 1");
headers = curl_slist_append(headers, "Authorization: Basic eXaMpLe1234");
headers = curl_slist_append(headers, "Content-Type: application/json");
headers = curl_slist_append(headers, "Cookie: __cfruid=2c9eb500bc16cc34cd7390604b24ece125e7e8ad-187187187");
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
const char *data = "{ \"user\": {\"external_id\": \"160102\", \"name\" : \"TestÜÄÖ\", \"phone\": \"014567-0\", \"user_fields\": { \"anrede\": \"Herr\"}, \"organization\":{\"name\":\"testorg\"}, \"email\" : \"\"} }";
curl_easy_setopt(curl, CURLOPT_POSTFIELDS, data);
res = curl_easy_perform(curl);
}
curl_easy_cleanup(curl);
is there a configuration in VS that i have to do to tell him i want utf-8 encoding when posting data?
"charset utf-8" in header yields the same results
Edit: sending a basic curl with the same data using windows cmd behaves the same and saved umlauts as questionmarks, even tho postman generated that curl statement which works when postman sends it.
for people googling:
the u8 prefix as commented by Botje worked

POST request fails while using libcurl, C++

TEST(ApiTest, TestPostMethod) {
CURL *curl;
CURLcode res;
curl_global_init(CURL_GLOBAL_ALL);
curl = curl_easy_init();
if (curl) {
curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "POST");
std::string url = "https://postman-echo.com/post";
curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
curl_easy_setopt(curl, CURLOPT_DEFAULT_PROTOCOL, "https");
struct curl_slist *headers = NULL;
// curl_slist_append(headers, "HOST: postman-echo.com");
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
res = curl_easy_perform(curl);
curl_easy_cleanup(curl);
ASSERT_EQ(CURLE_OK, res);
}
}
Error: CURLE_COULDNT_RESOLVE_HOST (6)
When I tested this POST request on postman it worked as expected. Also curl command
curl --location --request POST 'https://postman-echo.com/post'
works fine.
Expected equality of these values:
CURLE_OK
Which is: 0
res
Which is: 6
Run NSLOOKUP as suggested by #Andreas Wenzel
> postman-echo.com
Server: 75.75.75.75
Address: 75.75.75.75#53
Non-authoritative answer:
Name: postman-echo.com
Address: 3.210.84.203
Name: postman-echo.com
Address: 52.22.211.29
https://github.com/alexzk1/ed_highway/blob/master/utils/restclient.cpp
this works for many sites last 3-4 years. you can pick those 2 files only.
It uses CURLOPT_POSTFIELDS for post.
Btw, in your code u're following redirects, are u sure website don't redirect you to non-existing link?
Sorry. I figured this out. My server on which I was run this has restrictions in connecting with outside world. Thanks everyone for looking into this.

cURL 404 behind proxy

Just a simple file download test. Not working. Probaby because of the proxy at a Company. How can I configure the proxy?
Before adding "127.0.0.1:8080" I always got error 7: Could not connect to server. Now I always get return code 0, but the test file json.txt contains only a 404. But the url is obviously working in my browser. I also tried to get proxy settings from system via this, but I failed.
HTTP/1.1 404 Not Found
Connection: Keep-Alive
Server: Embedthis-http
ETag: "0-0-56d6b6ea"
Cache-Control: no-cache
Last-Modified: Wed, 02 Mar 2016 09:48:26 GMT
Date: Fri, 19 May 2017 14:33:57 GMT
Content-Length: 167
Keep-Alive: timeout=60, max=199
<!DOCTYPE html>
<html><head><title>Not Found</title></head>
<body>
<h2>Access Error: 404 -- Not Found</h2>
<pre>Cannot locate document: /</pre>
</body>
</html>
Here is my cURL attempt:
CURL *curl;
FILE *fp;
char url[] = "http://www.carqueryapi.com/api/0.3/?callback=?&cmd=getMakes&year=2010&sold_in_us=1";
char outfilename[FILENAME_MAX] = "C:\\temp\\json.txt";
curl = curl_easy_init();
if (curl) {
fp = fopen(outfilename,"wb");
CURLcode res;
curl_easy_setopt(curl, CURLOPT_URL, url );
curl_easy_setopt(curl, CURLOPT_NOBODY, true);
curl_easy_setopt(curl, CURLOPT_HEADER, true);
curl_easy_setopt(curl, CURLOPT_HTTPGET, true);
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
curl_easy_setopt(curl, CURLOPT_WRITEDATA, fp);
curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1 );
curl_easy_setopt(curl, CURLOPT_PROXY, "127.0.0.1:8080" );
res = curl_easy_perform(curl);
cout << "Curl response code " << res << ": " << curl_easy_strerror( res ) << endl;
curl_easy_cleanup(curl);
fclose(fp);
}
UPDATE
The internet settings are configured to use the wpad.dat file to detect proxies. If I enter one of those, I get a response from the server, but it says the access is denied because the website is blocked. But my browser can display this site.
On the contrary, if I enter netsh.exe winhttp show proxy it says that the current winhttp proxy settings are "direct access (no proxy server)".
UPDATE 2
I finally got it working with those options: Used Verbose to get more helpful output; output showed some auth method like negotiate and ntlm; the ntlm option did not work but the negotiateone together with the userpwd : which takes the credentials from the system, if libcurl has the sspi module.
curl_easy_setopt(curl, CURLOPT_URL, url );
curl_easy_setopt(curl, CURLOPT_VERBOSE, 1 );
curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1 );
curl_easy_setopt(curl, CURLOPT_HEADER, 1);
curl_easy_setopt(curl, CURLOPT_HTTPAUTH, CURLAUTH_ANY );
curl_easy_setopt(curl, CURLOPT_PROXY, <"host:port"> );
curl_easy_setopt(curl, CURLOPT_PROXYAUTH, CURLAUTH_NEGOTIATE );
curl_easy_setopt(curl, CURLOPT_PROXYUSERPWD, ":" );
Try user agent and define header.
#define HEADER_ACCEPT "Accept:text/html,application/xhtml+xml,application/xml"
#define HEADER_USER_AGENT "User-Agent:Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.17 (KHTML, like Gecko) Chrome/24.0.1312.70 Safari/537.17"
struct curl_slist *list = NULL;
list = curl_slist_append(list, HEADER_USER_AGENT);
list = curl_slist_append(list, HEADER_ACCEPT);
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, list);
You may need a real proxy, find a proxy sites, and retry with another ip

libcurl, enabling chunk encoding with multipart form data

What i want to achieve is to be able to upload a file of any size and also send post data in the same request. The server is guaranteed to be able to handle chunked encoding and also support unlimited size of size.
To achieve that I used CURLOPT_HTTPOST and set the header Transfer-Encoding: chunked, The problem is that I'm am not sure if libcurl is actually using chunked encoding at all. In my attempts to try and figure out I set CURLOPT_VERBOSE to 1 and implemented a custom debug callback to monitor the http headers. From curl I can only see 1 HTTP Request and only 1 HTTP Response (code 200). I didn't see any http code 201 responses.
My question is how do I enable chunk encoding for file uploads in multipart POST requests? If what I'm doing is correct why does libcurl not show me all the requests, how do I make sure it works like it is required?
Bellow is a short example of what I am doing in code.
//Assume `curl` has been initialised
struct curl_httppost *formpost=NULL;
struct curl_httppost *lastptr=NULL;
struct curl_slist *headerlist=NULL;
curl_formadd(&formpost,
&lastptr,
CURLFORM_COPYNAME,
"foo",
CURLFORM_COPYCONTENTS,
"bar",
CURLFORM_END);
curl_formadd(&formpost,
&lastptr,
CURLFORM_COPYNAME,
"file",
CURLFORM_FILE,
"filepath",
CURLFORM_FILENAME,
"filename",
CURLFORM_END);
headerlist = curl_slist_append(headerlist, "Transfer-Encoding: chunked");
curl_easy_setopt(curl, CURLOPT_URL, "https://foo/uploadfile");
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist);
curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, curl_write_to_string);
curl_easy_setopt(curl, CURLOPT_XFERINFOFUNCTION, curl_progress_cb);
curl_easy_setopt(curl, CURLOPT_XFERINFODATA, &progress_id);
curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 0L);
curl_easy_setopt(curl, CURLOPT_WRITEDATA, &response);
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 1);
CURLcode res = curl_easy_perform(curl);
Thanks in advance