Reading data from private channel using suggested mathlab code. I get a read error ...

I am in the process of building a small ESP8266 driven data screen thingy thing ... that would show some data from a private thingspeak channel. In recognition of a need for security I wish to use SSL.

I have adjusted the Mathlab code to suit my situation, but for some reason I keep getting an error 400 which is a bad request from the client side (I.e. Me not thingspeak)

I have read and re-read my code and would now like a fresh pair of eyes to spot the obvious error.

/*
  ReadMultipleFields
  
  Hardware: ESP8266 based boards
  
  
*/

#define TS_ENABLE_SSL // For HTTPS SSL connection

#include <ESP8266WiFi.h>
#include <WiFiClientSecure.h>
#include "secrets.h"
#include "ThingSpeak.h" // always include thingspeak header file after other header files and custom macros

char ssid[] = SECRET_SSID;   // your network SSID (name) 
char pass[] = SECRET_PASS;   // your network password
int keyIndex = 0;            // your network key Index number (needed only for WEP)
WiFiClientSecure  client;

// setup channel variables
unsigned long chl111 = SECRET_CH_ID;
const char * chl111_api = SECRET_READ_APIKEY_COUNTER;
unsigned int counterFieldNumber = 0;

int statusCode = 0;
long int field[4] = {1,2,3,4};



// Fingerprint check, make sure that the certificate has not expired.
const char * fingerprint = SECRET_SHA1_FINGERPRINT; // use SECRET_SHA1_FINGERPRINT for fingerprint check

void setup() {
  Serial.begin(115200);      // Initialize serial 
  while (!Serial) {
    ; // wait for serial port to connect. Needed for Leonardo native USB port only
  }
  
  WiFi.mode(WIFI_STA);
  
 if(fingerprint!=NULL){
    client.setFingerprint(fingerprint);
  }
  else{
    client.setInsecure(); // To perform a simple SSL Encryption
  }  
 
  ThingSpeak.begin(client);  // Initialize ThingSpeak

  // Connect or reconnect to WiFi
  if(WiFi.status() != WL_CONNECTED){
    Serial.print("Attempting to connect to SSID: ");
    Serial.println(SECRET_SSID);
    while(WiFi.status() != WL_CONNECTED){
      WiFi.begin(ssid, pass); // Connect to WPA/WPA2 network. Change this line if using open or WEP network
      Serial.print(".");
      delay(5000);     
    } 
    Serial.println("\nConnected");
  }
}

void loop() {

    
    // Read and store all the latest field values, location coordinates, status message, and created-at timestamp
    // use ThingSpeak.readMultipleFields(channelNumber, readAPIKey) for private channels
    statusCode = ThingSpeak.readMultipleFields(chl111,chl111_api);
    
    if(statusCode == 200)
    {
      // Fetch the stored data

     int calcTemp = ThingSpeak.getFieldAsInt(field[1]);// Field 1
     int mBarRaw = ThingSpeak.getFieldAsInt(field[2]); // Field 2
     int mBarMSL = ThingSpeak.getFieldAsInt(field[3]); // Field 3
     int calcAlt = ThingSpeak.getFieldAsInt(field[4]); // Field 4
   /*   String statusMessage = ThingSpeak.getStatus(); // Status message
      String latitude = ThingSpeak.getLatitude(); // Latitude
      String longitude = ThingSpeak.getLongitude(); // Longitude
      String elevation = ThingSpeak.getElevation(); // Elevation
      String createdAt = ThingSpeak.getCreatedAt(); // Created-at timestamp
   */   
      Serial.println("Calculation Temp): " + String(calcTemp));
      Serial.println("Raw Air Pressure: " + String(mBarRaw));
      Serial.println("Adjust Air Pressure to MSL " + String(mBarMSL));
      Serial.println("Altitude (M): " + String(calcAlt));
    /*  Serial.println("Status Message, if any: " + statusMessage);
      Serial.println("Latitude, if any (+ve is North, -ve is South): " + latitude);
      Serial.println("Longitude, if any (+ve is East, -ve is West): " + longitude);
      Serial.println("Elevation, if any (meters above sea level): " + elevation);
      Serial.println("Created at, if any (YYYY-MM-DD hh:mm:ss): " + createdAt);
      */
    }
    else{
      Serial.println("Problem reading channel. HTTP error code " + String(statusCode)); 
    }

    Serial.println();
    delay(10000); // no need to fetch too often
       

[John D Smith]

Oh dear oh dearie me ...

Caught by the old O and 0 in the API key. I rather stupidly typed the read api into secrets rather than copy and paste from my browser.

Possibly a good addition to help files would be that very suggestion ... I have been a clutz before and had this happen. Reassuring I had the code kinda right though :-) I have posted this as a comment that it might help others.

Great result however ...

Connected
Calculation Temp): 989
Raw Air Pressure: 1010
Adjust Air Pressure to MSL 176
Altitude (M): 
*/

Which is fine, however in my paniced attempt at getting it to read I changed the field numbers, and blocked out possible error lines.... Here is the intended result I was looking for.

Connected
Calculation Temp): 8
Raw Air Pressure: 989
Adjust Air Pressure to MSL 1010
Altitude (M): 176
Status Message, if any: 
Latitude, if any (+ve is North, -ve is South): 
Longitude, if any (+ve is East, -ve is West): 
Elevation, if any (meters above sea level): 
Created at, if any (YYYY-MM-DD hh:mm:ss): 2021-08-29T00:41:43Z

The fun thing to do now is build a code to feed this data into a database of my own, that is used to trigger a frost machine in my vege garden.

All fun and games in lockdown :-)

[John D Smith]

What has happened to Sha1 security ... I am not a close follower of the news on thingspeak ... has there been a change in the way ssl is done?.

[Walter Roberson]

@John D Smith

SHA1 has been forbidden for all but root certificates since no later than 2017. https://serverfault.com/questions/837994/why-are-ca-root-certificates-all-sha-1-signed-since-sha-1-is-deprecated

[John D Smith]

I have lost faith in the world therefore the world is no longer trusted :-) ... thanks for the reply.

Answer 1

[John D Smith]

See comment on my question above ... was a typing error in the read api key.

Yes I know eliminate the obvious first then ask questions ...