How to publish on Pubnub with node mcu?

Question

I have node mcu and i am trying to use the example code on github and pubnub blog to send a msg as an experiment but can't figure how to do it.

I used 2 example as the reference - https://github.com/pubnub/arduino , https://www.pubnub.com/docs/arduino/data-streams-publish-and-subscribe

Here is the code which i have. I modified it to include some libraries and my API keys. Let me know what changes i have to make:-

#include <ESP8266WiFi.h>
#define PubNub_BASE_CLIENT WiFiClient
#define PUBNUB_DEFINE_STRSPN_AND_STRNCASECMP
#include <PubNub.h>
String pubkey = "pub-c-4a9cdbca-5688-4939-a852-f63cf6743980";
String subkey = "sub-c-9b4067ae-1293-11e9-b4a6-026d6924b094";
String pubchannel = "sec-c-NmFiYjliODYtMTc3Mi00YTMzLTg0OWMtMDgzYjE2ZGUwNzg5";
void setup() {
 /* For debugging, set to speed of your choice */
 Serial.begin(9600);
 /* Start the Pubnub library by giving it a publish and subscribe
 keys */
 PubNub.begin(pubkey, subkey);
}
void loop() {
 /* Maintain DHCP lease. For other HW, you may need to do
 something else here, or maybe nothing at all. */
 /* Publish message. You could use `auto` here... */
 PubNonSubClient *pclient = PubNub.publish(pubchannel, "\"message\"");
 if (!pclient) return;
 PublishCracker cheez;
 cheez.read_and_parse(pclient);
 /** You're mostly interested in `outcome()`, and,
 if it's "failed", then `description()`. 
 */
 Serial.print("Outcome: "); Serial.print(cheez.outcome());
 Serial.print(' '); Serial.println(cheez.to_str(cheez.outcome()));
 Serial.print("description: "); Serial.println(cheez.description());
 Serial.print("timestamp: "); Serial.println(cheez.timestamp());
 Serial.print("state: "); Serial.print(cheez.state());
 Serial.print(' '); Serial.println(cheez.to_str(cheez.state()));
 pclient->stop();
 /* Wait for news. */
 PubSubClient *sclient = PubNub.subscribe(subchannel);
 if (!sclient) return; // error
 String msg;
 SubscribeCracker ritz(sclient);
 while (!ritz.finished()) {
 ritz.get(msg);
 if (msg.length() > 0) {
 Serial.print("Received: "); Serial.println(msg);
 }
 }
 sclient->stop();
 delay(1000);
}
Error:-
node_mcu_test_code:44:46: error: 'subchannel' was not declared in this scope
 PubSubClient *sclient = PubNub.subscribe(subchannel);
 ^
node_mcu_test_code:54:14: error: 'class PubSubClient' has no member named 'stop'
 sclient->stop();
 ^
exit status 1
no matching function for call to 'PubNub::begin(String&, String&)'

• Juraj: what is subchannel? pubchannel?
• Jaromanda X: #include <PubSubClient.h> - why? no demos or docs say you need to do that
• Sultan Morbiwala: <PubSubClient> is what I found in old forums so put that just for checking. I specified sub and pubchannel with API key. If not like that then how to do it.
• Jaromanda X: is what I found in old forums so put that just for checking don't add things without knowing what they do
• Jaromanda X: also, you've not declared a variable called subchannel ... yet you try to use a variable called subchannel ... which is why you get an error that states error: 'subchannel' was not declared in this scope - because it isn't

Answer 1

The pubchannel and subchannel can be defined as any values in char variable.

Here is the right code:-

const char * pubkey = "publisher key from your account";
const char * subkey = "subscriber key from your account";
const char * pubchannel = "demo_keyset";
const char * subchannel = "demo_keyset";

Then the error disappeared