Custom token auth

[peterz0310]

Hi,
I'm having some trouble getting custom tokens to work with this library. I think I'm following the example, but still getting unexpected errors. For my project, I need to fetch the token at runtime. This may be a totally separate problem, but I think I'm doing it right. Either way, even if I generate the token and use it in the example file (not at runtime), I still get errors. I am testing on an ESP32-S3. This code works perfect with user_auth, but custom_token does not work. I'm confident that the tokens I fetch are valid since this is the same exact function that I used with your Firebase_ESP_Client library and it worked there. Can you please take a look at this? Thanks.

#include <Arduino.h>
#include <WiFi.h>
#include <FirebaseClient.h>
#include <WiFiClientSecure.h>
#include <ArduinoJson.h>
#include <HTTPClient.h>

#define API_KEY "AIzaSy..."
#define DATABASE_URL "https://database-url.com/"

#define CLOUD_FUNCTION_URL "https://generatecustomtoken-....run.app"

#define WIFI_SSID "ssid"
#define WIFI_PASSWORD "pass"

#define USERNAME "[email protected]"
#define PASSWORD "Password1"

String deviceID = "123";
String userID = "QvWGFjShpvd...";

void asyncCB(AsyncResult &aResult);

DefaultNetwork network;

CustomToken *custom_token = nullptr;
UserAuth user_auth(API_KEY, USERNAME, PASSWORD, 3000);

FirebaseApp app;

WiFiClientSecure ssl_client;

using AsyncClient = AsyncClientClass;

AsyncClient aClient(ssl_client, getNetwork(network));

RealtimeDatabase Database;

AsyncResult aResult_no_callback;

void setup() {
  Serial.begin(115200);
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);

  Serial.print("Connecting to Wi-Fi");
  unsigned long ms = millis();
  while (WiFi.status() != WL_CONNECTED) {
    Serial.print(".");
    delay(300);
  }
  Serial.println();
  Serial.print("Connected with IP: ");
  Serial.println(WiFi.localIP());
  Serial.println();

  ssl_client.setInsecure();

  app.setCallback(asyncCB);

  //initializeApp(aClient, app, getAuth(user_auth));

  String customToken = fetchCustomToken();
  Serial.println("Token: " + customToken);

  custom_token = new CustomToken(API_KEY, customToken, 3000);
  if (custom_token != nullptr) {
    Serial.println("Initializing app...");
    initializeApp(aClient, app, getAuth(*custom_token));
  } else {
    Serial.println("No custom token set.");
  }

  ms = millis();
  while (app.isInitialized() && !app.ready() && millis() - ms < 120 * 1000)
    ;

  app.getApp<RealtimeDatabase>(Database);

  Database.url(DATABASE_URL);

  //Async set
  Database.set<int>(aClient, "/test/int", 12345, asyncCB);
  //Async get
  Database.get(aClient, "/test/test_async", asyncCB);
}

void loop() {
  app.loop();
  Database.loop();
}

void asyncCB(AsyncResult &aResult) {
  if (aResult.appEvent().code() > 0) {
    Firebase.printf("Event msg: %s, code: %d\n", aResult.appEvent().message().c_str(), aResult.appEvent().code());
  }

  if (aResult.isDebug()) {
    Firebase.printf("Debug msg: %s\n", aResult.debug().c_str());
  }

  if (aResult.isError()) {
    Firebase.printf("Error msg: %s, code: %d\n", aResult.error().message().c_str(), aResult.error().code());
  }

  if (aResult.available()) {
    Firebase.printf("payload: %s\n", aResult.c_str());
  }
}

String fetchCustomToken() {
  HTTPClient http;
  http.begin(CLOUD_FUNCTION_URL);
  http.addHeader("Content-Type", "application/json");

  String payload = "{\"uid\":\"" + userID + "\",\"deviceId\":\"" + deviceID + "\"}";

  int httpResponseCode = http.POST(payload);

  if (httpResponseCode == 200) {
    String response = http.getString();
    Serial.println("HTTP Response code: " + String(httpResponseCode));

    DynamicJsonDocument doc(1024);
    deserializeJson(doc, response);
    const char *customToken = doc["token"];

    return customToken;
  } else {
    Serial.print("Error on sending POST: ");
    Serial.println(httpResponseCode);
    return "";
  }
}

This is the error I get:

Connecting to Wi-Fi.
Connected with IP: 192.168.0.113

HTTP Response code: 200
Token: eyJhbGciOiJSUzI1NiIsInR5c...
Event msg: auth request sent, code: 8
Debug msg: Terminating theEvent msg: authenticating, code: 7
Debug msg: Connecting to server...
Event msg: auth request sent, code: 8
Guru Meditation Error: Core  1 panic'ed (StoreProhibited). Exception was unhandled.

Core  1 register dump:
PC      : 0x420046b4  PS      : 0x00060630  A0      : 0x8200481e  A1      : 0x3fcebe30  
A2      : 0x8648862a  A3      : 0x3fcb319c  A4      : 0x00000000  A5      : 0x00000054 
...

As a side note, is there a place I can find what the codes mean?

Thanks for all the help with this.

Peter

[mobizt]

Thanks for reporting this.

I will check and update.

[mobizt]

This issue was fixed in library v1.0.5, please update.

[peterz0310]

Thanks so much that's exactly what I needed!

[peterz0310]

Just one more thing. Is there something in this library similar to your other library's preRefreshSeconds? I see that I can get a refresh token using app.getRefreshToken(), but is there a way to automatically refresh it so it never expires as long as the device is plugged in and connected to WiFi? Or should I schedule a ~55 minute call to initializeApp() with the refresh token as the custom token, like this CustomToken(API_KEY, refreshToken, 3000);? Or is there a more proper way to do it, since I see a refresh_token parameter in the example CustomToken custom_token(<api_key>, <custom_token>, <expire_in_seconds>, <refresh_token>);. Thanks.

[mobizt]

There is no such user confusing option.

The expire period in second or time to live period was used in class's constructor instead.

You can get the refresh token as you mentioned and pass to the second parameter (<custom_token>) of custom token class as I wrote in the example comment.

FirebaseClient/examples/App/AppInitialization/TokenAuth/CustomToken/CustomToken.ino

Line 43 in cd2ac8d

* By assign the refresh token as <custom_token>, the auth token will be re-authenticated when calling initializeApp.

Note that the typo in the syntax in the example comment.
There are only tree parameters for the custom token class, no fourth parameter for <refresh_token>.

FirebaseClient/examples/App/AppInitialization/TokenAuth/CustomToken/CustomToken.ino

Lines 35 to 42 in cd2ac8d

	* SYNTAX:
	*
	* CustomToken custom_token(<api_key>, <custom_token>, <expire_in_seconds>, <refresh_token>);
	*
	* <api_key> - API key can be obtained from Firebase console > Project Overview > Project settings.
	* <custom_token> - Auth custom token (jwt signed token).
	* <expire_in_seconds> - Expire period in seconds.
	*

The library will check that the second parameter (<custom_token>) is valid custom JWT token or not by finding two occurrences of dots in token string, otherwise it will treat this token as a refresh token and begin refresh immediately when calling InitializeApp.

Your device ever crashed because of this bug in token checking process that still treat your refresh token as a custom token.

The bug has now fixed.

[mobizt]

You also can check the time to live of token.

FirebaseClient/examples/App/AppInitialization/CustomAuth/CustomAuth.ino

Lines 297 to 298 in cd2ac8d

	// To get the authentication time to live in seconds before expired.
	// app.ttl();

[mobizt]

The major change from the old Firebase library is it uses millis timer for all timing processes except for the valid time required for signing JWT token.

This eliminates the issue when user changes or sets his device system time later after calling Firebase.begin that causes the wrong expiry period calculation in old library.