Initial Slack support

alertik.h

@@ -12,6 +12,5 @@
 
 	extern char *get_formatted_time(time_t time, char *time_str);
 	extern void log_msg(const char *fmt, ...);
-	extern int  send_telegram_notification(const char *msg);
 
 #endif /* ALERTIK_H */

notifiers.c

@@ -50,15 +50,14 @@ int is_within_notify_threshold(void) {
  *
  * @param hnd CURL handle.
  * @param url Request URL.
- * @return Returns CURLE_OK if successful, otherwise a CURLcode error.
+ * @return Returns 0.
  */
-static void setopts_get_curl(CURL *hnd, const char *url)
+static int setopts_get_curl(CURL *hnd, const char *url)
 {
 	curl_easy_setopt(hnd, CURLOPT_URL, url);
 	curl_easy_setopt(hnd, CURLOPT_NOPROGRESS,    1L);
 	curl_easy_setopt(hnd, CURLOPT_USERAGENT, CURL_USER_AGENT);
 	curl_easy_setopt(hnd, CURLOPT_MAXREDIRS,     3L);
-	curl_easy_setopt(hnd, CURLOPT_TCP_KEEPALIVE, 1L);
     curl_easy_setopt(hnd, CURLOPT_WRITEFUNCTION, libcurl_noop_cb);
 #ifdef CURL_VERBOSE
 	curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
@@ -66,14 +65,16 @@ static void setopts_get_curl(CURL *hnd, const char *url)
 #ifndef VALIDATE_CERTS
 	curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYPEER, 0L);
 #endif
+	return 0;
 }
 
 /**
  *
  */
-static void do_curl_cleanup(CURL *hnd, char *escape)
+static void do_curl_cleanup(CURL *hnd, char *escape, struct curl_slist *slist)
 {
 	curl_free(escape);
+	curl_slist_free_all(slist);
 	if (hnd)
 		curl_easy_cleanup(hnd);
 }
@@ -81,7 +82,7 @@ static void do_curl_cleanup(CURL *hnd, char *escape)
 /**
  *
  */
-static CURLcode do_curl(CURL *hnd, char *escape)
+static CURLcode do_curl(CURL *hnd, char *escape, struct curl_slist *slist)
 {
 	CURLcode ret_curl = !CURLE_OK;
 
@@ -97,7 +98,7 @@ static CURLcode do_curl(CURL *hnd, char *escape)
 
 	ret_curl = CURLE_OK;
 error:
-	do_curl_cleanup(hnd, escape);
+	do_curl_cleanup(hnd, escape, slist);
 	return ret_curl;
 }
 
@@ -105,17 +106,80 @@ error:
  * @brief Initializes and configures the CURL handle for sending a POST
  * request with a JSON payload.
  *
- * @param hnd      CURL handle.
+ * @param hnd           CURL handle.
- * @param url      Request URL.
+ * @param url           Request URL.
- * @param payload  Payload data in JSON format.
+ * @param json_payload  Payload data in JSON format.
  *
- * @return Returns CURLE_OK if successful, otherwise a CURLcode error.
+ * @return Returns 0 if successful, 1 otherwise.
  */
-static void setopts_post_json_curl(CURL *hnd, const char *url,
+static int setopts_post_json_curl(CURL *hnd, const char *url,
-	const char *payload)
+	const char *json_payload, struct curl_slist **slist)
 {
+	struct curl_slist *s  = *slist;
+
+	s = NULL;
+	s = curl_slist_append(s, "Content-Type: application/json");
+	s = curl_slist_append(s, "Accept: application/json");
+	if (!s) {
+		*slist = s;
+		return 1;
+	}
+
+	curl_easy_setopt(hnd, CURLOPT_HTTPHEADER,    s);
+	curl_easy_setopt(hnd, CURLOPT_URL,         url);
+	curl_easy_setopt(hnd, CURLOPT_NOPROGRESS,    1L);
+	curl_easy_setopt(hnd, CURLOPT_USERAGENT, CURL_USER_AGENT);
+	curl_easy_setopt(hnd, CURLOPT_MAXREDIRS,     3L);
+    curl_easy_setopt(hnd, CURLOPT_WRITEFUNCTION, libcurl_noop_cb);
+#ifdef CURL_VERBOSE
+	curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
+#endif
+#ifndef VALIDATE_CERTS
+	curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYPEER, 0L);
+#endif
+	curl_easy_setopt(hnd, CURLOPT_POSTFIELDS, json_payload);
+	*slist = s;
+	return 0;
 }
 
+/**
+ *
+ */
+static int send_generic_webhook(const char *url, const char *text)
+{
+	CURL *hnd               = NULL;
+	struct curl_slist *s    = NULL;
+	char payload_data[4096] = {0};
+
+	if (!(hnd = curl_easy_init())) {
+		log_msg("Failed to initialize libcurl!\n");
+		return 1;
+	}
+
+	snprintf(
+		payload_data,
+		sizeof payload_data - 1,
+		"{\"text\":\"%s\"}",
+		text
+	);
+
+
+	#if 0
+	TODO:
+	- escape "" in the payload, otherwise it will silently
+	escape from the {"text": }
+	- think about the return code from the request and
+	emmit some message if not 200
+	#endif
+
+	if (setopts_post_json_curl(hnd, url, payload_data, &s))
+		return 1;
+
+	log_msg("> Sending notification!\n");
+	return do_curl(hnd, NULL, s);
+}
+
+
 ////////////////////////////////////////////////////////////////////////////////
 //////////////////////////////// TELEGRAM //////////////////////////////////////
 ////////////////////////////////////////////////////////////////////////////////
@@ -143,7 +207,7 @@ void setup_telegram(void)
 	setup = 1;
 }
 
-int send_telegram_notification(const char *msg)
+static int send_telegram_notification(const char *msg)
 {
 	char full_request_url[4096] = {0};
 	char *escaped_msg = NULL;
@@ -157,7 +221,7 @@ int send_telegram_notification(const char *msg)
 	escaped_msg = curl_easy_escape(hnd, msg, 0);
 	if (!escaped_msg) {
 		log_msg("> Unable to escape notification message...\n");
-		do_curl_cleanup(hnd, escaped_msg);
+		do_curl_cleanup(hnd, escaped_msg, NULL);
 	}
 
 	snprintf(
@@ -167,11 +231,36 @@ int send_telegram_notification(const char *msg)
 		telegram_bot_token, telegram_chat_id, escaped_msg);
 
 	setopts_get_curl(hnd, full_request_url);
-
 	log_msg("> Sending notification!\n");
-
+	return do_curl(hnd, escaped_msg, NULL);
-	return do_curl(hnd, escaped_msg);
 }
+
+////////////////////////////////////////////////////////////////////////////////
+////////////////////////////////// SLACK ///////////////////////////////////////
+////////////////////////////////////////////////////////////////////////////////
+
+/* Slack settings. */
+static char *slack_webhook_url;
+
+void setup_slack(void)
+{
+	static int setup = 0;
+	if (setup)
+		return;
+
+	slack_webhook_url = getenv("SLACK_WEBHOOK_URL");
+	if (!slack_webhook_url) {
+		panic("Unable to find env vars for, please check if you have set\n"
+		      "the SLACK_WEBHOOK_URL!!\n");
+	}
+	setup = 1;
+}
+
+static int send_slack_notification(const char *msg) {
+	return send_generic_webhook(slack_webhook_url, msg);
+}
+
+
 ////////////////////////////////// END ////////////////////////////////////////
 ///////////////////////////////////////////////////////////////////////////////
 
@@ -185,5 +274,10 @@ struct notifier notifiers[] = {
 	{
 		.setup = setup_telegram,
 		.send_notification = send_telegram_notification
+	},
+	/* Slack. */
+	{
+		.setup = setup_slack,
+		.send_notification = send_slack_notification
 	}
 };