ThingSpeak

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in the below code write is working fine, but read is failing ( 404 error) can you please help me reslove this. /* Go to thingspeak.com and create an account if you don't have one already. After logging in, click on the "New Channel" button to create a new channel for your data. This is where your data will be stored and displayed. Fill in the Name, Description, and other fields for your channel as desired, then click the "Save Channel" button. Take note of the "Write API Key" located in the "API keys" tab, this is the key you will use to send data to your channel. Replace the channelID from tab "Channel Settings" and privateKey with "Read API Keys" from "API Keys" tab. Replace the host variable with the thingspeak server hostname "api.thingspeak.com" Upload the sketch to your ESP32 board and make sure that the board is connected to the internet. The ESP32 should now send data to your Thingspeak channel at the intervals specified by the loop function. Go to the channel view page on thingspeak and check the "Field1" for the new incoming data. You can use the data visualization and analysis tools provided by Thingspeak to display and process your data in various ways. Please note, that Thingspeak accepts only integer values. You can later check the values at https://thingspeak.com/channels/2005329 Please note that this public channel can be accessed by anyone and it is possible that more people will write their values. */ #include <WiFi.h> const char *ssid = "xxxx"; // Change this to your WiFi SSID const char *password = "xxxxx"; // Change this to your WiFi password const char *host = "api.thingspeak.com"; // This should not be changed const int httpPort = 80; // This should not be changed const String channelID = "2805914"; // Change this to your channel ID const String writeApiKey = "xxxxxxxxxxxxxxxx"; // Change this to your Write API key const String readApiKey = "xxxxxxxxxxxxxxxx"; // Change this to your Read API key // The default example accepts one data filed named "field1" // For your own server you can ofcourse create more of them. int field1 = 20; //int field1 = 20; int numberOfResults = 1; // Number of results to be read int fieldNumber = 1; // Field number which will be read out void setup() { Serial.begin(115200); while (!Serial) { delay(100); } // We start by connecting to a WiFi network Serial.println(); Serial.println("******************************************************"); Serial.print("Connecting to "); Serial.println(ssid); WiFi.begin(ssid, password); while (WiFi.status() != WL_CONNECTED) { delay(500); Serial.print("."); } Serial.println(""); Serial.println("WiFi connected"); Serial.println("IP address: "); Serial.println(WiFi.localIP()); } void readResponse(NetworkClient *client) { unsigned long timeout = millis(); while (client->available() == 0) { if (millis() - timeout > 5000) { Serial.println(">>> Client Timeout !"); client->stop(); return; } } // Read all the lines of the reply from server and print them to Serial while (client->available()) { String line = client->readStringUntil('\r'); Serial.print(line); } Serial.printf("\nClosing connection\n\n"); } void loop() { NetworkClient client; String footer = String(" HTTP/1.1\r\n") + "Host: " + String(host) + "\r\n" + "Connection: close\r\n\r\n"; // WRITE -------------------------------------------------------------------------------------------- if (!client.connect(host, httpPort)) { return; } client.print("GET /update?api_key=" + writeApiKey + "&field1=" + field1 + footer); readResponse(&client); delay(200); // READ -------------------------------------------------------------------------------------------- String readRequest = "GET /channels/" + channelID + "/fields/" + fieldNumber + ".json?results=" + numberOfResults + " HTTP/1.1\r\n" + "Host: " + host + "\r\n" + "Connection: close\r\n\r\n"; if (!client.connect(host, httpPort)) { return; } client.print(readRequest); readResponse(&client); // ------------------------------------------------------------------------------------------------- //++field1; delay(10000); } I am using example program WiFiClient, write is working fine, but read is giving error 404 A couple of comments: 404 is not found, so I would suggest a serial.println on this line so you can see what is actually getting sent. Then try it in your browser wndow you help you trouble shoot it. String readRequest = "GET /channels/" + channelID + "/fields/" + fieldNumber + ".json?results=" + numberOfResults + " HTTP/1.1\r\n" + "Host: " + host + "\r\n" + "Connection: close\r\n\r\n"; it should look something like this: https://api.thingspeak.com/channels/2005329/field/1.json?results=4 I would suggest explicitly including the host address (api.thingspeak.com). You can also try to verify that you have the channel ID correct. We really reccomend you use the ThingSpeak library for arduino. It takes care of a lot of hard work for you. You can definitely send non integer values to thingspeak. The interfect trats everything as a string, but then the thingspeak plots will attempt to interprest numbes as integers or floats or what have you. API keys are kind of like passwords, so I have redacted them in your code above. Good luck on your project, please let us know if you get it working! Hi Chris, Thanks for your response, I got it sloved, readApikey was missing i added it as in the below and the code worked. String readRequest = "GET /channels/" + channelID + "/fields/" + fieldNumber + ".json?api_key=" + readApiKey + "&results=" + numberOfResults + " HTTP/1.1\r\n" + "Host: " + host + "\r\n" + "Connection: close\r\n\r\n"; read 404 error