我無法使用 cURL 錯誤發送帶有不和諧 webhook 的消息：“無法發送空消息

Question

因此，我嘗試使用以下代碼向不和諧的 webhook 發送消息：

#include <iostream>
#include <curl/curl.h>

int main(void)
{
    CURL* curl;
    CURLcode res;

    const char* WEBHOOK = "webhookLink";
    const char* content = "test";

    curl_global_init(CURL_GLOBAL_ALL);

    curl = curl_easy_init();
    if (curl) {
        curl_easy_setopt(curl, CURLOPT_URL, WEBHOOK);

        curl_easy_setopt(curl, CURLOPT_POSTFIELDS, content);

        res = curl_easy_perform(curl);

        if (res != CURLE_OK)
            fprintf(stderr, "curl_easy_perform() failed: %s\n",
                curl_easy_strerror(res));

        curl_easy_cleanup(curl);
    }
    curl_global_cleanup();
}

我從 cURL 文檔中得到了這段代碼。 每次我運行它時，它都會在控制台中輸出{"message": "Cannot send an empty message", "code": 50006} 。

有任何想法嗎？

編輯：它與命令行一起使用

curl -i -H "Accept: application/json" -H "Content-Type:application/json" -X POST --data "{\"content\": \"Posted Via Command line\"}" $WEBHOOK_URL

Answer 1

您需要將Content-Type標頭添加到您的請求中。

示例（我沒有不和諧的 webhook，所以我無法測試它）：

#include <curl/curl.h>

#include <iostream>

int main(void) {
    CURL* curl;
    CURLcode res;

    const char* WEBHOOK = "webhookLink";
    const char* content = R"aw({"content": "Posted Via libcurl"})aw";

    curl_global_init(CURL_GLOBAL_ALL);

    curl = curl_easy_init();
    if(curl) {
        curl_easy_setopt(curl, CURLOPT_URL, WEBHOOK);

        // create a curl list of header rows:
        struct curl_slist* list = NULL;

        // add Content-Type to the list:
        list = curl_slist_append(list, "Content-Type: application/json");

        // set this list as HTTP headers:
        curl_easy_setopt(curl, CURLOPT_HTTPHEADER, list);

        curl_easy_setopt(curl, CURLOPT_POSTFIELDS, content);

        res = curl_easy_perform(curl);
        curl_slist_free_all(list);     // and finally free the list

        if(res != CURLE_OK)
            fprintf(stderr, "curl_easy_perform() failed: %s\n",
                    curl_easy_strerror(res));

        curl_easy_cleanup(curl);
    }
    curl_global_cleanup();
}

（還應添加額外的錯誤檢查）