HTTPClient and successive GET to different servers

[Patrick54]

Hi,

I am stuck with something that seems pretty simple. I have an ESP32 linked to my door bell. When someone rings at the door, I want it to post a message in a telegram group, and to trigger a scenario on my home automation system. These 2 actions are performed via the HTTPClient library, with the GET command.

Here is the code:

Code: [Select all] [Expand/Collapse]

1. #include <Arduino.h>
2. #include "WiFi.h"
3. #include <HTTPClient.h>
4.  
5. // Wifi parameters
6. #define WIFI_NETWORK "xxx"
7. #define WIFI_PASSWORD "yyy"
8. #define WIFI_TIMEOUT_MS 20000
9. #define HOSTNAME "esp32DoorBell"
10.  
11. // Button is on pin 15
12. #define BUTTON_PIN 15
13.  
14. // LED is on pin 18
15. #define LED_PIN 18
16.  
17. HTTPClient http;
18.  
19. void connectToWifi() {
20.   Serial.print("Connecting to Wifi");
21.   WiFi.mode(WIFI_STA);
22.   WiFi.setSleep(false);
23.   WiFi.begin(WIFI_NETWORK, WIFI_PASSWORD);
24.   WiFi.setHostname(HOSTNAME);
25.  
26.   unsigned long startAttemptTime = millis();
27.  
28.   while (WiFi.status() != WL_CONNECTED && (millis() - startAttemptTime) < WIFI_TIMEOUT_MS) {
29.     Serial.print(".");
30.     delay(500);
31.   }
32.  
33.   if (WiFi.status() != WL_CONNECTED) {
34.     Serial.println(" failed!");
35.   } else {
36.     Serial.print(" connected with IP address ");
37.     Serial.println(WiFi.localIP());
38.   }
39.  
40. }
41.  
42.  
43. void setup() {
44.   // Init serial connection
45.   Serial.begin(9600);
46.   Serial.println("Started");
47.  
48.   // Set button pin in input and LED pin to output
49.   pinMode(BUTTON_PIN, INPUT);
50.   pinMode(LED_PIN, OUTPUT);
51.  
52.   // We turn on the LED to indicate that Wifi connection is not active
53.   digitalWrite(LED_PIN, HIGH);
54.  
55.   // Allow reusing the HTTP connection
56.   http.setReuse(true);
57.  
58.   // connect to Wifi
59.   connectToWifi();
60.  
61. }
62.  
63. void loop() {
64.  
65.   // Check if Wifi has been disconnected, and reconnect if needed
66.  
67.   while (WiFi.status() != WL_CONNECTED) {
68.  
69.     // Turn on the LED to indicate that Wifi connection has been lost
70.     digitalWrite(LED_PIN, HIGH);
71.  
72.     Serial.println("Wifi disconnected, attemting to reconnect");
73.     connectToWifi();
74.     if (WiFi.status() != WL_CONNECTED) {
75.       Serial.println("Could not reconnect, wait 10 seconds");
76.       delay(10000);
77.     }
78.   }
79.  
80.   // If we reach this point, it means that Wifi connection is OK, so we turn off the LED
81.   digitalWrite(LED_PIN, LOW);
82.  
83.   // Read the state of the button
84.   int PushButtonState = digitalRead(BUTTON_PIN);
85.   int httpCode;
86.   String payload;
87.  
88.   if (PushButtonState == HIGH ) {
89.  
90.     Serial.println("Button is on");
91.  
92.     // Call a Jeedom scenario
93.  
94.     http.begin("https://mydomain.com/core/api/jeeApi.php?apikey=xxx&type=scenario&id=3&action=start");
95.     httpCode = http.GET();
96.  
97.     if (httpCode > 0) {
98.  
99.         payload = http.getString();
100.        
101.         Serial.println(httpCode);
102.         Serial.println(payload);
103.     } else {
104.       Serial.println("Error on HTTP request");
105.     }
106.    
107.    
108.     http.end();
109.  
110.     Serial.println("After call to jeedom");
111.  
112.     // Send a notification via Telegram
113.  
114.     http.begin("https://api.telegram.org/bot1234:theKey/sendMessage?chat_id=-6789&text=test+esp32");
115.     httpCode = http.GET();
116.  
117.     if (httpCode > 0) {
118.  
119.         payload = http.getString();
120.         Serial.println(httpCode);
121.         Serial.println(payload);
122.     } else {
123.       Serial.println("Error on HTTP request");
124.     }
125.  
126.     http.end();
127.  
128.     Serial.println("After call to telegram");
129.  
130.     // Delay of 500 ms to avoid multiple execution
131.  
132.     delay(500);
133.   }
134.  
135.   delay(25);
136. }
137.  

GeSHi © Codebox Plus Extension

When the door bell is triggered, I get this output:

Code: Select all

Started
Connecting to Wifi. connected with IP address 192.168.107.10
HTTP server started
Button is on
200
ok
After call to jeedom
404
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>404 Not Found</title>
</head><body>
<h1>Not Found</h1>
<p>The requested URL was not found on this server.</p>
</body></html>

After call to telegram

We can see that the call to my home automation system is working fine, but the second call to telegram fails.
If I change the order of the calls, I can successfully post the message on telegram, but the call to my home automation system fails with an HTTP code 302.

What am I doing wrong here?

[Patrick54]

I have found a workaround, by creating 2 distinct HTTPClient variables. But I still would like to understand what is happening