Google's Firebase Realtime Database Arduino Library for ESP32 v3.9.4
This library supports ESP32 MCU from Espressif. The following are platforms in which libraries are also available.
The Firebase Client for ESP8266 and ESP32 supports Cloud Firestore, Firebase Storage, Google Cloud Storage and new API Cloud Messaging and Cloud Functions for Firebase is now available.
Please try it here https://github.com/mobizt/Firebase-ESP-Client
- NodeMCU-32
- WEMOS LOLIN32
- TTGO T8 V1.8
Most ESP32 boards are supported unless Sparkfun ESP32 Thing (old version) is not recommended due to it built with non-standard 26 MHz clock on board instead of 40 MHz which causes the bugs and unstable network connection.
The library access the internet through WiFi or Ethernet connection, the ESP32 based module that may has Mobile network modem i.e. 2G (GPRS), 3G or 4G built-in modules cannot use if it accesses the internet trourgh these modules by sending the AT commands.
The others UART/Serial bridge mobile network modem which work with AT commands and ESP32 AT commands were unsupported.
-
Supports Read (get), Store (set), Append (push), Patch (update) and Delete Data
-
Supports Primitive data types: Integer, Float, Double, Boolean, String and JSON.
-
Supports BLOB and File Stream Data.
-
Support Read and Write Database Rules.
-
Supports ETag, Priority, Data Limits, Timestamp, Filtering, etc.
-
Supports Stream Event Callbacks
-
Supports Multiple paths Stream (under the same parent node)
-
Supports Email/Password, custom and access token authentications using Service Account
-
Supports Data Backup and Restore.
-
Supports Firebase Cloud Messaging.
-
Supports SD and Flash's CA certificate file.
-
Built-in easiest and non-recursive JSON parser and builder.
-
Supports Ethernet using LAN8720, TLK110 and IP101 Ethernet boards.
Don't be confused with other Firebase Arduino libraries, this library has different working functions, the following examples provide the basic usages.
ESP32 | FLUTTER | FIREBASE - Temperature & Humidity Check App
Serverless IoTs with Firebase Realtime Database and ESP32 - Part 1
Serverless IoTs with Firebase Realtime Database and ESP32 - Part 2
This library required ESP32 Core SDK version 1.0.1 or above.
For Arduino IDE, ESP32 Core SDK can be installed through Boards Manager.
For PlatfoemIO IDE, ESP32 Core SDK can be installed through PIO Home > Platforms > Espressif 32.
At Arduino IDE, go to menu Sketch -> Include Library -> Manage Libraries...
In Library Manager Window, search "firebase" in the search form then select "Firebase ESP32 Client"
Click "Install" button.
For PlatformIO IDE, using the following command.
pio lib install "Firebase ESP32 Client"
Or at PIO Home -> Library -> Registry then search Firebase ESP32 Client.
For Arduino IDE, download zip file from the repository (Github page) by select Clone or download dropdown at the top of repository, select Download ZIP
From Arduino IDE, select menu Sketch -> Include Library -> Add .ZIP Library....
Choose Firebase-ESP32-master.zip that previously downloaded.
Go to menu Files -> Examples -> Firebase-ESP32-master and choose one from examples.
For PlatformIO, in folder "lib", create new folder named "Firebase-ESP32" and add these files in that folder.
See All examples for complete usages.
See Function description for all available functions.
//Include WiFi.h
#include <WiFi.h>
//Include Firebase ESP32 library (this library)
#include <FirebaseESP32.h>
//Define the Firebase Data object
FirebaseData fbdo;
// Define the FirebaseAuth data for authentication data
FirebaseAuth auth;
// Define the FirebaseConfig data for config data
FirebaseConfig config;
// Assign the project host and api key (required)
config.host = FIREBASE_HOST;
config.api_key = API_KEY;
// Assign the user sign in credentials
auth.user.email = USER_EMAIL;
auth.user.password = USER_PASSWORD;
//Initialize the library with the Firebase authen and config.
Firebase.begin(&config, &auth);
//Optional, set AP reconnection in setup()
Firebase.reconnectWiFi(true);
//Optional, set number of error retry
Firebase.setMaxRetry(fbdo, 3);
//Optional, set number of error resumable queues
Firebase.setMaxErrorQueue(fbdo, 30);
//Optional, use classic HTTP GET and POST requests.
//This option allows get and delete functions (PUT and DELETE HTTP requests) works for
//device connected behind the Firewall that allows only GET and POST requests.
Firebase.enableClassicRequest(fbdo, true);
//Optional, set the size of HTTP response buffer
//Prevent out of memory for large payload but data may be truncated and can't determine its type.
fbdo.setResponseSize(8192); //minimum size is 4096 bytes
See Other authentication examples for more sign in methods.
This library supports many types of authentications.
See Other authentication examples for more authentication methods.
Some authentication methods require the token generaion and exchanging process which take more time than using the legacy token.
The system time must be set before authenticate using the custom and OAuth2.0 tokens or when the root certificate was set for data transfer.
The authentication with custom and OAuth2.0 tokens takes the time, several seconds in overall process which included the NTP time acquisition (system time setup), JWT token generation and signing process.
By setting the system time prior to calling the Firebase.begin
, the internal NTP time acquisition process will be ignored.
You can set the system time using the RTC chip or manually by calling Firebase.setSystemTime
.
While authenticate using Email and password, the process will be perform faster because no token generation and time setup required.
The authenticate using the legacy token (database secret) does not have these delay time because the token is ready to use.
Some users may have the question why the time for sending/receiving data with this library was increased when using the different authentication methods which someone compare with other libraries and platforms.
Once the token is ready for authentication, the data transmission time will depend on the time used in SSL/TLS handshake process (only for new session opening), the size of http header (included auth token size) and payload to be transmitted and the SSL client buffer reserved size especially in ESP8266.
The legacy token size is relatively small, only 40 bytes, result in smallest header to send, while the size of id token generated using Email/Password is quite large, approx. 900 bytes. result in larger header to send.
There is a compromise between the speed of data transfer and the Rx/Tx buffer which then reduced the free memory available especially in ESp8266.
When the reserved SSL client Rx/Tx buffer is smaller than the size of data to be transmitted, the data need to be sent as multiple chunks which required more transmission time.
This affected especially in ESP8266 which has the limited free memory.
To speed up the data transmission in ESP8266, the larger reserved Rx/Tx buffer size is necessary.
The reserved SSL Rx/Tx buffer size in ESP8266 can be set through the function <Firebase Data object>.setBSSLBufferSize, e.g. fbdo.setBSSLBufferSize(2048, 2048);
The larger BearSSL buffer reserved for ESP8266, the lower free memory available as long as the session opened (server connection).
Therefore the time for data transfer will be varied from approx. neary 200 ms to 500 ms based on the reserved SSL client Rx/Tx buffer size and the size of data to transmit.
In ESP8266, when the free memory and speed are concerned, the legacy token should be used instead of other authentication to reduce the header size and the lower SSL Rx/Tx buffer i.e. 1024 for Rx and 512 for Tx are enough.
When the session was reused (in this library), the SSL handshake process will be ignored in the subsequence requests.
The session was close when the host or ip changes or server closed or the session timed out in 3 minutes.
When the new session need to be opened, the SSL handshake will be processed again and used the time approx 1 - 2 seconds to be done.
For post (push) or put (set) request in RTDB, to speed up the data transfer, use pushAsync or setAsync instead.
With pushAsync and setAsync, the payload response will be ignored and the next data will be processed immediately.
To use Email/Password sign-in authentication as in the examples, the Email/Password Sign-in provider must be enabled.
To get API Key used in Email/Password sign-in
To get the Service accounts key JSON file used in Custom and OAuth2.0 tokens athentications.
The Firebase Host and database secret for RTDB usages.
Data at a specific node in Firebase RTDB can be read through these get functions.
The functions included get
, getInt
, getFloat
, getDouble
, getBool
, getString
, getJSON
, getArray
, getBlob
, getFile
.
These functions return boolean value indicates the success of the operation which will be true
if all of the following conditions were met.
-
Server returns HTTP status 200
-
The data types matched between request and response.
The database data's payload (response) can be read or access through the following Firebase Data object's functions.
-
fbdo.intData
-
fbdo.floatData
-
fbdo.doubleData
-
fbdo.boolData
-
fbdo.stringData
-
fbdo.jsonString
-
fbdo.jsonObject
-
fbdo.jsonObjectPtr
-
fbdo.jsonArray
-
fbdo.jsonArrayPtr
-
fbdo.jsonData
(for keeping parse/get result)
and
fbdo.blobData
Read the data which its type does not match the data type in the database from above functions will return empty (string, object or array).
The data type of returning payload can be determined by fbdo.getDataType
.
BLOB and file stream data are store as special base64 encode string which only supported and implemented by this library.
The encoded string will be prefixed with some header string ("file,base64," and "blob,base64,") for data type manipulation.
The following example showed how to read integer value from "/test/int".
if (Firebase.getInt(fbdo, "/test/int")) {
if (fbdo.dataType() == "int")) {
Serial.println(fbdo.intData());
}
} else {
Serial.println(fbdo.errorReason());
}
To store data at a specific node in Firebase RTDB, use these set functions.
The function included set
, setInt
, setFloat
, setDouble
, setBool
, setString
, setJSON
, setArray
, setBlob
and setFile
.
The above functions return boolean value indicates the success of the operation which will be true
if all of the following conditions matched.
-
Server returns HTTP status 200
-
The data types matched between request and response.
Only setBlob and setFile functions that make a silent request to Firebase server, thus no payload response returned.
The priority, virtual node ".priority" of each database node can be set through Firebase's set functions.
The priority value can be used in a query or filtering the children's data under a defined database path.
ETag (unique identifier value) assigned to Firebase's set functions is used as conditional checking.
If defined Etag is not matched the defined path's ETag, the set operation will fail with result 412 Precondition Failed.
ETag at any database path can be read through Firebase.getETag
. ETag value changed upon the data was set or delete.
The server's Timestamp can be stored in the database through Firebase.setTimestamp
.
The returned Timestamp value can get from fbdo.getInt()
.
The following example showed how to store file data to Flash memory at "/test/file_data".
if (Firebase.getFile(fbdo, StorateType::FLASH, "/test/file_data", "/test.txt"))
{
//FLASH.begin(); //not need to begin again due to it has been called in function.
File file = FLASH.open("/test.txt", "r");
while (file.available())
{
Serial.print(file.read(), HEX);
}
file.close();
Serial.println();
} else {
Serial.println(fbdo.fileTransferError());
}
To append new data to a specific node in Firebase RTDB, use these push functions.
The function included push
, pushInt
, pushFloat
, pushDouble
, pushBool
, pushString
, pushJSON
, pushArray
, pushBlob
, and pushFile
.
These functions return boolean value indicates the success of the operation.
The unique key of a new appended node can be determined from fbdo.pushName
.
As get functions, the Firebase's push functions support priority.
ETag was not available after push unless read the ETag at that new appended unique key later with Firebase.getETag
.
The server's Timestamp can be appended in the database through Firebase.pushTimestamp
.
The unique key of Timestamp can be determined after Timestamp was appended.
The following example showed how to append new data (using FirebaseJson object) to "/test/append.
FirebaseJson json;
FirebaseJson json2;
json2.set("child_of_002", 123.456);
json.set("parent_001", "parent 001 text");
json.set("parent 002", json2);
if (Firebase.pushJSON(fbdo, "/test/append", json)) {
Serial.println(fbdo.dataPath());
Serial.println(fbdo.pushName());
Serial.println(fbdo.dataPath() + "/"+ fbdo.pushName());
} else {
Serial.println(fbdo.errorReason());
}
Firebase's update functions used to patch or update new or existing data at the defined database path.
These functions, updateNode
and updateNodeSilent
are available and work with JSON object (FirebaseJson object only)
If any key provided at a defined database path in JSON object has not existed, a new key will be created.
The server returns JSON data payload which was successfully patched.
Return of large JSON payload will cost the network data, alternative function updateNodeSilent
should be used to save the network data.
The following example showed how to patch data at "/test".
FirebaseJson updateData;
FirebaseJson json;
json.set("_data2","_value2");
updateData.set("data1","value1");
updateData.set("data2", json);
if (Firebase.updateNode(fbdo, "/test/update", updateData)) {
Serial.println(fbdo.dataPath());
Serial.println(fbdo.dataType());
Serial.println(fbdo.jsonString());
} else {
Serial.println(fbdo.errorReason());
}
The following example showed how to delete data and its children at "/test/append"
Firebase.deleteNode(fbdo, "/test/append");
To filter or query the data, the following query parameters are available through the QueryFilter class.
These parameters are orderBy
, limitToFirst
, limitToLast
, startAt
, endAt
, and equalTo
.
To filter data, parameter orderBy
should be assigned.
Use "$key" as the orderBy
parameter if the key of child nodes was used for the query.
Use "$value" as the orderBy
parameter if the value of child nodes was used for the query.
Use key (or full path) of child nodes as the orderBy
parameter if all values of the specific key were used for the query.
Use "$priority" as orderBy
parameter if child nodes's "priority" was used for query.
The above orderBy
parameter can be combined with the following parameters for limited and ranged the queries.
QueryFilter.limitToFirst
- The total children (number) to filter from the first child.
QueryFilter.limitToLast
- The total last children (number) to filter.
QueryFilter.startAt
- Starting value of range (number or string) of query upon orderBy param.
QueryFilter.endAt
- Ending value of range (number or string) of query upon orderBy param.
QueryFilter.equalTo
- Value (number or string) matches the orderBy param
The following example showed how to use queries parameter in QueryFilter class to filter the data at "/test/data"
//Assume that children that have key "sensor" are under "/test/data"
//Instantiate the QueryFilter class
QueryFilter query;
//Build query using specified child node key "sensor" under "/test/data"
query.orderBy("sensor");
//Query any child that its value begins with 2 (number), assumed that its data type is float or integer
query.startAt(2);
//Query any child that its value ends with 8 (number), assumed that its data type is float or integer
query.endAt(8);
//Limit the maximum query result to return only the last 5 nodes
query.limitToLast(5);
if (Firebase.getJSON(fbdo, "/test/data", query))
{
//Success, then try to read the JSON payload value
Serial.println(fbdo.jsonString());
}
else
{
//Failed to get JSON data at defined database path, print out the error reason
Serial.println(fbdo.errorReason());
}
//Clear all query parameters
query.clear();
This library uses HTTP GET request with stream header to connect the stream.
The Firebase's functions that involved the stream operation are beginStream
, beginMultiPathStream
,
setStreamCallback
, setMultiPathStreamCallback
and/or readStream
.
Function beginStream
is to subscribe to the stream changes at a defined database path.
Function beginMultiPathStream
is to subscribe to the stream changes at a defined parent node path with multiple child nodes value parsing and works with setMultiPathStreamCallback.
Function setStreamCallback
is to assign the callback function that accept the StreamData class as parameter.
Function setMultiPathStreamCallback
is to assign the callback function that accept the MultiPathStreamData class as parameter.
The StreamData contains stream event and data and interface function calls are similar to Firebase Data object.
The MultiPathStreamData contains stream event and data for various child nodes.
To check the stream manually, use readStream
.
Function readStream
used in the loop() task to continuously read the stream changes event and data.
After readStream
, determine the availability of stream with Firebase Data object function fbdo.streamAvailable
Function fbdo.streamAvailable
returned true when new stream data was available.
When new stream data was available, its data and event can be accessed from Firebase Data object functions.
-
fbdo.intData
-
fbdo.floatData
-
fbdo.doubleData
-
fbdo.boolData
-
fbdo.stringData
-
fbdo.jsonString
-
fbdo.jsonObject
-
fbdo.jsonObjectPtr
-
fbdo.jsonArray
-
fbdo.jsonArrayPtr
-
fbdo.jsonData
(for keeping parse/get result)
and
fbdo.blobData
Function endStream
ends the stream operation.
Note that, when using the shared Firebase Data object for stream and other usages i.e. normal operation to read and store data, the stream will be interrupted to use in other tassks, the stream will be resumed (reconnection) after that normal usage was finished.
For the above case, you need to provide the free time for stream to listen to the server event data. The changes on the server at the streaming node path during the stream interruption will be missed.
To avoid this sitation, don't share the usagge of stream's Firebase Data object, use other Firebase Data object instead.
In addition, delay function used in the same loop block of readStream() will interrupt the stream operation, the server data changes may be missed.
More use of Firebase Data object at the same scope i.e more than 2 can lead to out of memory error as the most memory used in Firebase Data object is due to SSL client.
The following example showed how to subscribe to the stream changes at "/test/data" with a callback function.
//In setup(), set the stream callback function to handle data
//streamCallback is the function that called when database data changes or updates occurred
//streamTimeoutCallback is the function that called when the connection between the server
//and client was timeout during HTTP stream
Firebase.setStreamCallback(fbdo, streamCallback, streamTimeoutCallback);
//In setup(), set the streaming path to "/test/data" and begin stream connection
if (!Firebase.beginStream(fbdo, "/test/data"))
{
//Could not begin stream connection, then print out the error detail
Serial.println(fbdo.errorReason());
}
//Global function that handles stream data
void streamCallback(StreamData data)
{
//Print out all information
Serial.println("Stream Data...");
Serial.println(data.streamPath());
Serial.println(data.dataPath());
Serial.println(data.dataType());
//Print out the value
//Stream data can be many types which can be determined from function dataType
if (data.dataType() == "int")
Serial.println(data.intData());
else if (data.dataType() == "float")
Serial.println(data.floatData(), 5);
else if (data.dataType() == "double")
printf("%.9lf\n", data.doubleData());
else if (data.dataType() == "boolean")
Serial.println(data.boolData() == 1 ? "true" : "false");
else if (data.dataType() == "string")
Serial.println(data.stringData());
else if (data.dataType() == "json")
Serial.println(data.jsonString());
}
//Global function that notifies when stream connection lost
//The library will resume the stream connection automatically
void streamTimeoutCallback(bool timeout)
{
if(timeout){
//Stream timeout occurred
Serial.println("Stream timeout, resume streaming...");
}
}
For multiple paths stream, see the MultiPath_stream example.
The following example showed how to subscribe to the stream changes at "/test/data" and read the stream manually.
//In setup(), set the streaming path to "/test/data" and begin stream connection
if (!Firebase.beginStream(fbdo, "/test/data"))
{
Serial.println(fbdo.errorReason());
}
//In loop()
if (!Firebase.readStream(fbdo))
{
Serial.println(fbdo.errorReason());
}
if (fbdo.streamTimeout())
{
Serial.println("Stream timeout, resume streaming...");
Serial.println();
}
if (fbdo.streamAvailable())
{
if (fbdo.dataType() == "int")
Serial.println(fbdo.intData());
else if (fbdo.dataType() == "float")
Serial.println(fbdo.floatData(), 5);
else if (fbdo.dataType() == "double")
printf("%.9lf\n", fbdo.doubleData());
else if (fbdo.dataType() == "boolean")
Serial.println(fbdo.boolData() == 1 ? "true" : "false");
else if (fbdo.dataType() == "string")
Serial.println(fbdo.stringData());
else if (fbdo.dataType() == "json")
Serial.println(fbdo.jsonString());
}
This library allows you to backup and restores the database at the defined path.
The backup file will store in SD card or Flash memory (FLASH).
Due to SD library used, only 8.3 DOS format file name supported.
The maximum 8 characters for a file name and 3 characters for file extension.
The database restoration returned completed status only when Firebase server successfully updates the data.
Any failed operation will not affect the database (no updates or changes).
The following example showed how to backup all database data at "/" and restore.
String backupFileName = "";
if (!Firebase.backup(fbdo, StorateType::SD, "/", "/backup.txt"))
{
Serial.println(fbdo.fileTransferError());
}
else
{
Serial.println(fbdo.getBackupFilename());
Serial.println(fbdo.getBackupFileSize());
backupFileName = fbdo.getBackupFilename();
}
//Begin restore backed dup data back to database
if (!Firebase.restore(fbdo, StorateType::SD, "/", backupFileName))
{
Serial.println(fbdo.fileTransferError());
}
else
{
Serial.println(fbdo.getBackupFilename());
}
When read store, append and update operations were failed due to buffer overflow and network problems.
These operations can retry and queued after the retry amount was reached maximum retry set in function setMaxRetry
.
//set maximum retry amount to 3
Firebase.setMaxRetry(fbdo, 3);
The function setMaxErrorQueue
limits the maximum queues in Error Queue collection.
The full of queue collection can be checked through function isErrorQueueFull
.
//set maximum queues to 10
Firebase.setMaxErrorQueue(fbdo, 10);
//determine whether Error Queue collection is full or not
Firebase.isErrorQueueFull(fbdo);
This library provides two approaches to run or process Error Queues with two functions.
beginAutoRunErrorQueue
processErrorQueue
The function beginAutoRunErrorQueue
will run or process queues automatically and can be called once.
While function processErrorQueue
will run or process queues and should call inside the loop().
With function beginAutoRunErrorQueue
, you can assigned callback function that accept QueueInfo object as parameter.
Which contains all information about being processed queue, number of remaining queues and Error Queue collection status.
Otherwise, Error Queues can be tracked manually with the following functions.
Function getErrorQueueID
will return the unsigned integer presents the id of the queue which will keep using later.
Use getErrorQueueID
and isErrorQueueExisted
to check whether this queue id is still existed or not.
If Error Queue ID does not exist in Error Queues collection, that queue is already done.
The following example showed how to run Error Queues automatically and track the status with the callback function.
//In setup()
//Set the maximum Firebase Error Queues in collection (0 - 255).
//Firebase read/store operation causes by network problems and buffer overflow will be
//added to Firebase Error Queues collection.
Firebase.setMaxErrorQueue(fbdo, 10);
//Begin to run Error Queues in Error Queue collection
Firebase.beginAutoRunErrorQueue(fbdo, callback);
//Use to stop the auto run queues
//Firebase.endAutoRunErrorQueue(fbdo);
void errorQueueCallback (QueueInfo queueinfo){
if (queueinfo.isQueueFull())
{
Serial.println("Queue is full");
}
Serial.print("Remaining queues: ");
Serial.println(queueinfo.totalQueues());
Serial.print("Being processed queue ID: ");
Serial.println(queueinfo.currentQueueID());
Serial.print("Data type:");
Serial.println(queueinfo.dataType());
Serial.print("Method: ");
Serial.println(queueinfo.method());
Serial.print("Path: ");
Serial.println(queueinfo.path());
Serial.println();
}
The following example showed how to run Error Queues and track its status manually.
//In setup()
//Set the maximum Firebase Error Queues in collection (0 - 255).
//Firebase read/store operation causes by network problems and buffer overflow will be added to
//Firebase Error Queues collection.
Firebase.setMaxErrorQueue(fbdo, 10);
//All of the following are in loop()
Firebase.processErrorQueue(fbdo);
//Detrnine the queue status
if (Firebase.isErrorQueueFull(fbdo))
{
Serial.println("Queue is full");
}
//Remaining Error Queues in Error Queue collection
Serial.print("Remaining queues: ");
Serial.println(Firebase.errorQueueCount(fbdo));
//Assumed that queueID is unsigned integer array of queue that added to Error Queue collection
//when error and use Firebase.getErrorQueueID to get this Error Queue id.
for (uint8_t i = 0; i < LENGTH_OF_QUEUEID_ARRAY; i++)
{
Serial.print("Error Queue ");
Serial.print(queueID[i]);
if (Firebase.isErrorQueueExisted(fbdo, queueID[i]))
Serial.println(" is queuing");
else
Serial.println(" is done");
}
Serial.println();
Error Queues can be saved as a file in SD card or Flash memory with function saveErrorQueue
.
Error Queues store as a file can be restored to Error Queue collection with function restoreErrorQueue
.
Two types of storage can be assigned with these functions, StorageType::FLASH
and StorageType::SD
.
Read data (get) operation is not support queues restore
The following example showed how to restore and save Error Queues in /test.txt file.
//To restore Error Queues
if (Firebase.errorQueueCount(fbdo, "/test.txt", StorageType::FLASH) > 0)
{
Firebase.restoreErrorQueue(fbdo, "/test.txt", StorageType::FLASH);
Firebase.deleteStorageFile("/test.txt", StorageType::FLASH);
}
//To save Error Queues to file
Firebase.saveErrorQueue(fbdo, "/test.txt", StorageType::FLASH);
Two types of FCM message data can be sent using this library e.g. notification and custom data.
These two types of data can send all together or separately.
Function Firebase.sendMessage
will send a message to one recipient.
Function Firebase.broadcastMessage
will broadcast or send a message to multiple recipients.
Function Firebase.sendTopic
will send a message to any recipient who subscribed to the topic.
The FCM message itself offers a broad range of messaging options and capabilities for various recipient device platforms.
For Android, iOS and web platforms, these basic options can be set and work for all platforms.
Function fbdo.fcm.begin
used to assign the server key of your Firebase project.
Function fbdo.fcm.addDeviceToken
used to add recipient registered device token which wants to send message to.
Functions fbdo.fcm.removeDeviceToken
and fbdo.fcm.clearDeviceToken
used to remove or clear recipient device.
For the notification message, title, body, icon (optional), and click_action (optional) can be set through fbdo.fcm.setNotifyMessage
.
And clear these notify message data with fbdo.fcm.clearNotifyMessage
.
For the data message, provide your custom data as JSON object (FirebaseJson object or string) to fbdo.fcm.setDataMessage
which can be clear with fbdo.fcm.clearDataMessage
.
The other options are priority
, collapse key
, Time to Live
of the message and topic
to send messages to, can be set from the following functions.
Call fbdo.fcm.setPriority
for priority ("normal" or "high"), fbdo.fcm.setCollapseKey
for collapse key setup, fbdo.fcm.setTimeToLive
for life span of message setup between 0 sec. to 2,419,200 sec. (or 4 weeks), and fbdo.fcm.setTopic
for assigning the topic that message to send to.
The following example showed how to send FCM message.
//Provide your Firebase project's server key here
fbdo.fcm.begin(FIREBASE_FCM_SERVER_KEY);
//Prvide one or more the recipient registered token or instant ID token
fbdo.fcm.addDeviceToken(FIREBASE_FCM_DEVICE_TOKEN);
//Provide the priority (optional)
fbdo.fcm.setPriority("normal");
//Provide the time to live (optional)
fbdo.fcm.setTimeToLive(5000);
//Set the notification message data
fbdo.fcm.setNotifyMessage("Notification", "Hello World!", "firebase-logo.png", "http://www.google.com");
//Set the custom message data
fbdo.fcm.setDataMessage("{\"myData\":\"myValue\"}");
//Send message to one recipient with inddex 1 (index starts from 0)
if (Firebase.sendMessage(fbdo, 1))
{
//Success, print the result returned from server
Serial.println(fbdo.fcm.getSendResult());
}
else
{
//Failed, print the error reason
Serial.println(fbdo.errorReason());
}
This library has built-in FirebaseJson Arduino library, the non-recursive easiest JSON parser, builder and editor.
FirebaseJson usages are so simple as you read, store and update(edit) the JSON node in Firebase RTDB.
It doesn't use the recursive call to parse or deserialize complex or nested JSON objects and arrays.
This makes the library can use with a limited stack memory device.
Since you declare the FirebaseJson (object) or FirebaseJsonArray, use the functions setJsonData
, add
, set
and remove
to build or edit JSON object and use get
to parse the node's contents.
Defined the relative path of the specific node to add
, set
, remove
and get
functions to add, set, remove and get its contents.
Function FirebaseJson.setJsonData
is to set the JSON string to JSON object.
Function FirebaseJson.add
is used to add the new node with the contents e.g. String, Number (int and double), Boolean, Array and Object to the defined relative path.
Function FirebaseJson.set
is used for edit, overwrite, create new (if not exist) node with contents e.g. String, Number (int and double), Boolean, Array and Object at the defined relative path.
Function FirebaseJson.remove
is used to remove the node and all its children's contents at the defined relative path.
Function FirebaseJson.toString
is used for (pretty or plain) print out the JSON object as Arduino string (this function takes String param).
Functions FirebaseJson.iteratorBegin
, FirebaseJson.iteratorGet
and FirebaseJson.iteratorEnd
are used for parse all JSON object contents as list which can be iterated with index.
Function FirebaseJson.clear
is used for clear JSON object contents.
Function FirebaseJsonArray.add
is used for adding the new contents e.g. String, Number (int and double), Boolean, Array and Object to JSON array.
Function FirebaseJsonArray.set
is for edit, overwrite, create new (if not exist) contents e.g. String, Number (int and double), Boolean, Array and Object at the defined relative path or defined index of JSON array.
Function FirebaseJsonArray.remove
is used to remove the array's contents at the defined relative path or defined index of JSON array.
Function FirebaseJsonArray.toString
is used for (pretty or plain) print out the JSON array object as Arduino string (this function takes String param).
Function FirebaseJsonArray.clear
is used for clear JSON object contents.
To acquired the JSON object or JSON Array from FirebaseData object which returned from the get, set, push operations, these following functions are required.
FirebaseData.jsonObject
FirebaseData.jsonObjectPtr
FirebaseData.jsonArray
and
FirebaseData.jsonArrayPtr
Function FirebaseData.jsonObject
and FirebaseData.jsonObjectPtr
will provide FirebaseJson (object) and FirebaseJson pointer respectively.
Function FirebaseData.jsonArray
and FirebaseData.jsonArrayPtr
will provide FirebaseJson Array and FirebaseJson Array pointer respectively.
The following example shows how to use FirebaseJson.
//Declare FirebaseJson object (global or local)
FirebaseJson json;
//Add name with value Living Room to JSON object
json.add("name", "Living Room");
//Add temp1 with value 120 and temp1 with 40 to JSON object
//Note: temp2 is not the child of temp1 as in previous version.
json.add("temp1", 120).add("temp2", 40);
//Add nested child contents directly
json.set("unit/temp1", "Farenheit");
json.set("unit/temp2", "Celcius");
//To print out as prettify string
String jsonStr;
json.toString(jsonStr, true);
Serial.println(jsonStr);
/*
This is the result of the above code
{
"name": "Living Room",
"temp1": 120,
"temp2": 40,
"unit": {
"temp1": "Farenheit",
"temp2": "Celcius"
}
}
*/
//To set array to the above JSON using FirebaseJson directly
//Set (add) array indexes 0,1,2,5,7 under temp1, the original value will be replaced with new one.
json.set("temp1/[0]", 47);
json.set("temp1/[1]", 28);
json.set("temp1/[2]", 34);
json.set("temp1/[5]", 23); //null will be created at array index 3,4 due to it's not yet assigned
json.set("temp1/[7]", 25); //null will be created at array index 6
//Print out as prettify string
json.toString(jsonStr, true);
Serial.println(jsonStr);
/*
The result of the above code
{
"name": "Living Room",
"temp1": [
47,
28,
34,
null,
null,
23,
null,
25
],
"temp2": 40,
"unit": {
"temp1": "Farenheit",
"temp2": "Celcius"
}
}
*/
//Try to remove temp1 array at index 1
json.remove("temp1/[1]");
//Try to remove temp2
json.remove("temp2");
//Print out as prettify string
json.toString(jsonStr, true);
Serial.println(jsonStr);
/*
The result of the above code
{
"name": "Living Room",
"temp1": [
47,
34,
null,
null,
23,
null,
25
],
"unit": {
"temp1": "Farenheit",
"temp2": "Celcius"
}
}
*/
//Now parse/read the contents from specific node unit/temp2
//FirebaseJsonData is required to keep the parse results which can be accessed later
FirebaseJsonData jsonData;
json.get(jsonData, "unit/temp2");
if (jsonData.success)
{
//Print type of parsed data e.g string, int, double, bool, object, array, null and undefined
Serial.println(jsonData.type);
//Print its content e.g.string, int, double, bool whereas object, array and null also can access as string
Serial.println(jsonData.stringValue);
//Serial.println(jsonData.intValue);
//Serial.println(jsonData.boolValue);
//Serial.println(jsonData.floatValue);
//Serial.println(jsonData.doubleValue);
}
//The above code will show
/*
string
Celcius
*/
//To get the array temp from FirebaseJson
json.get(jsonData, "temp1");
//Prepare FirebaseJsonArray to take the array from FirebaseJson
FirebaseJsonArray myArr;
//Get array data
jsonData.getArray(myArr);
//Call get with FirebaseJsonData to parse the array at defined index i
for (size_t i = 0; i < myArr.size(); i++)
{
//jsonData now used as temporary object to get the parse results
myArr.get(jsonData, i);
//Print its value
Serial.print("Array index: ");
Serial.print(i);
Serial.print(", type: ");
Serial.print(jsonData.type);
Serial.print(", value: ");
Serial.println(jsonData.stringValue);
}
/*
The result of above code
Array index: 0, type: int, value: 47
Array index: 1, type: int, value: 34
Array index: 2, type: null, value: null
Array index: 3, type: null, value: null
Array index: 4, type: int, value: 23
Array index: 5, type: null, value: null
Array index: 6, type: int, value: 25
*/
The following example shows how to use FirebaseJsonArray.
//Declare FirebaseJsonArray object (global or local)
FirebaseJsonArray arr;
//Add some data
arr.add("banana");
arr.add("mango");
arr.add("coconut");
//Change the array contents
arr.set("[1]/food", "salad");
arr.set("[1]/sweet", "cake");
arr.set("[1]/appetizer", "snack");
arr.set("[2]", "apple"); // or arr.set(2, "apple");
arr.set("[4]/[0]/[1]/amount", 20);
//Print out array as prettify string
String arrStr;
arr.toString(arrStr, true);
Serial.println(arrStr);
/*
This is the result of the above code
[
"banana",
{
"food": "salad",
"sweet": "cake",
"appetizer": "snack"
},
"apple",
null,
[
[
null,
{
"amount": 20
}
]
]
]
*/
//Remove array content at /4/0/1/amount
arr.remove("[4]/[0]/[1]/amount");
//Print out as prettify string
arr.toString(arrStr, true);
Serial.println(arrStr);
/*
The result of the above code
[
"banana",
{
"food": "salad",
"sweet": "cake",
"appetizer": "snack"
},
"apple",
null,
[
[
null
]
]
]
*/
//Now parse/read the array contents at some index
FirebaseJsonData jsonData;
arr.get(jsonData, "[1]/food");
if(jsonData.success)
{
//Type of parsed data
Serial.println(jsonData.type);
//Its value
Serial.println(jsonData.stringValue);
//Serial.println(jsonData.intValue);
//Serial.println(jsonData.boolValue);
//Serial.println(jsonData.floatValue);
//Serial.println(jsonData.doubleValue);
}
//The above code will show
/*
string
salad
*/
//To get the JSON object at array index 1 from FirebaseJsonArray
arr.get(jsonData, "[1]");// or arr.get(jsonData, 1);
//Prepare FirebaseJson to take the JSON object from FirebaseJsonArray
FirebaseJson myJson;
//Get FirebaseJson data
jsonData.getJSON(myJson);
//Parse the JSON object as list
//Get the number of items
size_t len = myJson.iteratorBegin();
String key, value = "";
int type = 0;
for (size_t i = 0; i < len; i++)
{
//Get the item at index i, whereas key and value are the returned data
myJson.iteratorGet(i, type, key, value);
//Print the data
Serial.print(i);
Serial.print(", ");
Serial.print("Type: ");
Serial.print(type == FirebaseJson::JSON_OBJECT ? "object" : "array");
if (type == FirebaseJson::JSON_OBJECT)
{
Serial.print(", Key: ");
Serial.print(key);
}
Serial.print(", Value: ");
Serial.println(value);
}
//Clear all list to free memory
myJson.iteratorEnd();
/*
The result of the above code
0, Type: object, Key: food, Value: salad
1, Type: object, Key: sweet, Value: cake
2, Type: object, Key: appetizer, Value: snack
*/
The MIT License (MIT)
Copyright (c) 2021 K. Suwatchai (Mobizt)
Permission is hereby granted, free of charge, to any person returning a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.