Blynk is a platform with iOS and Android apps to control Arduino, Raspberry Pi and the likes over the Internet.
You can easily build graphic interfaces for all your projects by simply dragging and dropping widgets.
If you need more information, please follow these links:
- Blynk site
- Blynk docs
- Blynk community
- App Store
- Google Play
- Blynk library
- Kickstarter
Blynk Server is an Open-Source Netty based Java server, responsible for forwarding messages between Blynk mobile application and various microcontroller boards (i.e. Arduino, Raspberry Pi. etc). Download latest server build here.
Java 8 required. (OpenJDK, Oracle). Installation instructions here.
By default, mobile application uses 8443 port and is based on SSL/TLS sockets. Default hardware port is 8442 and is based on plain TCP/IP sockets.
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Make sure you are using Java 8
java -version Output: java version "1.8.0_40"
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Run the server on default 'hardware port 8442' and default 'application port 8443' (SSL port)
java -jar server-0.15.3.jar -dataFolder /path
That's it!
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As output you will see something like that :
Blynk Server successfully started. All server output is stored in current folder in 'logs/blynk.log' file.
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Login to Raspberry Pi via ssh;
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Install java 8 :
sudo apt-get install oracle-java8-jdk
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Make sure you are using Java 8
java -version Output: java version "1.8.0_40"
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Download Blynk server jar file (or manually copy it to raspberry via ssh and scp command) :
wget "https://github.com/blynkkk/blynk-server/releases/download/v0.15.3/server-0.15.3.jar"
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Run the server on default 'hardware port 8442' and default 'application port 8443' (SSL port)
java -jar server-0.15.3.jar -dataFolder /home/pi/Blynk
That's it!
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As output you will see something like that :
Blynk Server successfully started. All server output is stored in current folder in 'logs/blynk.log' file.
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To enable server auto restart find /etc/init.d/rc.local file and add :
java -jar /home/pi/server-0.15.3.jar -dataFolder /home/pi/Blynk &
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Or in case above approach doesn't work for you, execute
crontab -e
add the following line
@reboot java -jar /home/pi/server-0.15.3.jar -dataFolder /home/pi/Blynk &
save and exit.
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Create bat file :
start-blynk.bat
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Put in it one line :
java -jar server-0.15.3.jar -dataFolder /home/pi/Blynk
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Put bat file to windows startup folder
In order to update your server with new version you need to kill old process and start new one.
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Find process id of Blynk server
ps -aux | grep java
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You will see something like that
username 10539 1.0 12.1 3325808 428948 pts/76 Sl Jan22 9:11 java -jar server-0.15.3.jar
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Kill old process
kill 10539
10539 - blynk server process id from command output above.
- Start new server as usual
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Open Task Manager;
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Find Java process;
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Stop process;
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Start new server as usual
- Specify custom server path in your application
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Change your ethernet sketch from
Blynk.begin(auth);
to
Blynk.begin(auth, "your_host");
or to
Blynk.begin(auth, IPAddress(xxx,xxx,xxx,xxx));
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Change your WIFI sketch from
Blynk.begin(auth, SSID, pass));
to
Blynk.begin(auth, SSID, pass, "your_host");
or to
Blynk.begin(auth, SSID, pass, IPAddress(XXX,XXX,XXX,XXX));
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Change your rasp PI javascript from
var blynk = new Blynk.Blynk(AUTH, options = {connector : new Blynk.TcpClient()});
to
var blynk = new Blynk.Blynk(AUTH, options= {addr:"xxx.xxx.xxx.xxx"});
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or in case of USB when running blynk-ser.sh provide '-s' option with address of your local server
./blynk-ser.sh -s you_host_or_IP
WARNING : Blynk is growing very quickly. And both apps and server constantly updated. In order to avoid problems during updates either turn off auto-update for Blynk app either update both local server and blynk app at same time to avoid possible migration issues.
WARNING : Blynk local server is not Blynk cloud server. They are not related at all. So you have to create new account when using Blynk local server.
If you need more flexibility, you can extend server with more options by creating server.properties file in same folder as server.jar. Example could be found here. server.properties options:
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Application mutual ssl/tls port
app.ssl.port=8443
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Hardware plain tcp/ip port
hardware.default.port=8442
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Hardware ssl/tls port (for hardware that supports SSL/TLS sockets)
hardware.ssl.port=8441
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For simplicity Blynk already provides server jar with build-in SSL certificates, so you have working server out of the box via SSL/TLS sockets. But as certificate and it's private key are in public this is totally not secure. So in order to fix that you need to provide your own certificates. And change below properties with path to your cert. and private key and it's password. See how to generate self-signed certificates here
#points to cert and key that placed in same folder as running jar. server.ssl.cert=./server_embedded.crt server.ssl.key=./server_embedded.pem server.ssl.key.pass=pupkin123
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Web socket ssl/tls port
ssl.websocket.port=8081
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Web sockets plain tcp/ip port
tcp.websocket.port=8082
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Https port
https.port=9443
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Http port
http.port=8080
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User profiles folder. Folder in which all users profiles will be stored. By default System.getProperty("java.io.tmpdir")/blynk used. Will be created if not exists
data.folder=/tmp/blynk
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Folder for all application logs. Will be created if it doesn't exist. "." is dir from which you are running script.
logs.folder=./logs
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Log debug level. Possible values: trace|debug|info|error. Defines how precise logging will be. From left to right -> maximum logging to minimum
log.level=trace
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Maximum allowed number of user dashboards.
user.dashboard.max.limit=10
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100 Req/sec rate limit per user.
user.message.quota.limit=100
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In case user exceeds quota limit - response error returned only once in specified period (in Millis).
user.message.quota.limit.exceeded.warning.period=60000
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Maximum allowed user profile size. In Kb's.
user.profile.max.size=128
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Maximum allowed number of notification queue. Queue responsible for processing email, pushes, twits sending. Because of performance issue - those queue is processed in separate thread, this is required due to blocking nature of all above operations. Usually limit shouldn't be reached
notifications.queue.limit=10000
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Number of threads for performing blocking operations - push, twits, emails, db queries. Recommended to hold this value low unless you have to perform a lot of blocking operations.
blocking.processor.thread.pool.limit=5
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Period for flushing all user DB to disk. In millis
profile.save.worker.period=60000
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Specifies maximum period of time when application socket could be idle. After which socket will be closed due to non activity. In seconds. Leave it empty for infinity timeout
app.socket.idle.timeout=600
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Specifies maximum period of time when hardware socket could be idle. After which socket will be closed due to non activity. In seconds. Leave it empty for infinity timeout
hard.socket.idle.timeout=15
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Mostly required for local servers setup in case user want to log raw data in CSV format. See [raw data] (https://github.com/blynkkk/blynk-server#raw-data-storage) section for more info.
enable.raw.data.store=true
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Administration UI https port
administration.https.port=7443
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Url for opening admin page. Must start from "/". For "/admin" url path will look like that "https://localhost:7443/admin".
admin.rootPath=/admin
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Comma separated list of administrator IPs. Allow access to admin UI only for those IPs. You may set it for 0.0.0.0/0 to allow access for all. You may use CIDR notation. For instance, 192.168.0.53/24.
allowed.administrator.ips=127.0.0.1
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Reset password server port. Separate API for password resetting.
reset.pass.http.port=7444
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Host for reset password redirect. By default current server IP is taken from "eth" network interface. Could be replaced with more friendly hostname. It is recommended to override this property with your server IP to avoid possible problems of host resolving.
reset-pass.http.host=blynk-cloud.com
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Comma separated list of users allowed to create accounts. Leave it empty if no restriction required.
Blynk server also has administration panel where you could monitor your server. It could be accessible with URL.
https://your_ip:7443/admin
You can change it with next options :
admin.rootPath
allowed.administrator.ips
administration.https.port
Blynk HTTP RESTful API allows to easily read and write values to/from Pins in Blynk apps and Hardware. For now API available only for Local Blynk Servers. Http API description could be found here.
In order to enable mail notifications on Local server you need to provide own mail credentials. To do that you need to create file mail.properties
within same folder where server.jar is.
Mail properties :
mail.smtp.auth=true
mail.smtp.starttls.enable=true
mail.smtp.host=smtp.gmail.com
mail.smtp.port=587
mail.smtp.username=YOUR_EMAIL_HERE
mail.smtp.password=YOUR_EMAIL_PASS_HERE
See example here.
NOTE : you'll need to setup Gmail to allow less secured applications. Go here and then click "Allow less secure apps".
In order to enable sms notifications on Local Server you need to provide credentials for sms gateway (for now Blynk server
supports only 1 provider - [Nexmo] (https://www.nexmo.com/)). So to do that you need to create file sms.properties
within same folder where server.jar is.
nexmo.api.key=
nexmo.api.secret=
And fill above properties with credentials you'll get from Nexmo. (Account -> Settings -> API settings). You also can send sms via email in case your cell provider supports that. See discussion for more details.
By default raw data storage is enabled. So any write (Blynk.virtualWrite) command will stored on disk. The default path is "data" folder within [data.folder] (https://github.com/blynkkk/blynk-server#advanced-local-server-setup) property of server properties.
File name format is
dashBoardId_pin.csv
For instance
data/1_v5.csv
Which means in 1_v5.csv file stored raw data for virtual pin 5 of dashboard with id 1.
Data format is
value,timestamp
For instance
10,1438022081332
Where 10 - value of pin, and 1438022081332 - the difference, measured in milliseconds, between the current time and midnight, January 1, 1970 UTC.
Raw data files are rotated every day and gzipped.
WARNING : this will changed in near future.
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Generate self-signed certificate and key
openssl req -x509 -nodes -days 1825 -newkey rsa:2048 -keyout server.key -out server.crt
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Convert server.key to PKCS#8 private key file in PEM format
openssl pkcs8 -topk8 -inform PEM -outform PEM -in server.key -out server.pem
WARNING : you should have password for certificate. Certificates without pass are not accepted. In case you connect hardware via USB script you have to provide an option '-s' pointing to "common name" (hostname) you did specified during certificate generation.
As output you'll retrieve server.crt and server.pem files that you need to provide for server.ssl properties.
sudo apt-add-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java8-installer
If you want to run Blynk server behind WiFi-router and want it to be accessible from the Internet, you have to add port-forwarding rule on your router. This is required in order to forward all of the requests that come to the router within the local network to Blynk server.
Currently server handles 20k req/sec with SSL and 40k req/sec without SSL hardware messages on VM with 2-cores of Intel(R) Xeon(R) CPU E5-2660 @ 2.20GHz. With high load - memory consumption could be up to 1 GB of RAM.