NodeJS BLE Applications using BLENO on Arch Linux

BLENO is a greate NodeJS based library for building applications that communicat with other devices (Smartphones, tables, sensor tags) using Bluetooth Low Energy (BLE).

This post is just to quickly document some requirements for successfully use the BLENO library, in my case, on Arch Linux running the latest Plasma (KDE) desktop.

The tools:

Most the information available on the internet for using and controlling the bluetooth adapter uses the now deprecated tools hcitool, hciconfig and so on. Check here the deprecated list of commands.

So we need to use the new tools from the latest Bluez (Bluetooth Linux implementation): btmgm, btinfo, …

Making Bleno examples work:

The simplest example to try out the BLENO library is the battery example located at: […]/bleno/examples/battery-service

First let’s check if our computer/laptop bluetooth adapter is available: Note that all commands must be ran as the root user:

root@pcortex:/opt/bleno/examples/battery-service# btinfo local
Bluetooth information utility ver 5.45
Failed to open HCI user channel
root@pcortex:/opt/bleno/examples/battery-service# 

This issue can be circumvented by stopping the higher level bluetooth stack:

root@pcortex:/opt/bleno/examples/battery-service# systemctl stop bluetooth
root@pcortex:/opt/bleno/examples/battery-service# btinfo local
Bluetooth information utility ver 5.45
HCI version: 6
HCI revision: 7869
LMP version: 6
LMP subversion: 64512
Manufacturer: 2
root@pcortex:/opt/bleno/examples/battery-service#

In case of previously disabling the Bluetooth through the graphical interface:

Disabling the Bluetooth here will have this behaviour (in this case the bluetooth service is still running):

root@pcortex:/opt/bleno/examples/battery-service# systemctl start bluetooth   (<- After this disable bluetooth on the graphical interface)
root@pcortex:/opt/bleno/examples/battery-service# btinfo local
Bluetooth information utility ver 5.45
Failed to open HCI user channel
root@pcortex:/opt/bleno/examples/battery-service# btmgmt power on
Set Powered for hci0 failed with status 0x12 (Blocked through rfkill)
root@pcortex:/opt/bleno/examples/battery-service# 

Even stopping the Bluetooth service keeps the BT adapter disabled:

root@pcortex:/opt/bleno/examples/battery-service# systemctl stop bluetooth
root@pcortex:/opt/bleno/examples/battery-service# btmgmt power on
Set Powered for hci0 failed with status 0x12 (Blocked through rfkill)
root@pcortex:/opt/bleno/examples/battery-service#

We can check this with the rfkill command:

root@pcortex:/opt/bleno/examples/battery-service# rfkill list
0: phy0: Wireless LAN
        Soft blocked: no
        Hard blocked: no
2: hci0: Bluetooth
        Soft blocked: yes
        Hard blocked: no
root@pcortex:/opt/bleno/examples/battery-service# 

We can unblock now the adapter:

root@pcortex:/opt/bleno/examples/battery-service# rfkill unblock 2
root@pcortex:/opt/bleno/examples/battery-service# rfkill list
0: phy0: Wireless LAN
        Soft blocked: no
        Hard blocked: no
2: hci0: Bluetooth
        Soft blocked: no
        Hard blocked: no
root@pcortex:/opt/bleno/examples/battery-service# btinfo local
Bluetooth information utility ver 5.45
HCI version: 6
HCI revision: 7869
LMP version: 6
LMP subversion: 64512
Manufacturer: 2
root@pcortex:/opt/bleno/examples/battery-service# btmgmt power on
hci0 class of device changed: 0x00010c
hci0 Set Powered complete, settings: powered bondable ssp br/edr le secure-conn 
root@pcortex:/opt/bleno/examples/battery-service# 

So why we are having all this work for making sure that the BT adapter is powered on AND the bluetooth stack is stopped (systemctl stop bluetooth).

The answer is quite simple. If we don’t do this the BLENO examples will seem to work (they start) but the BLE advertised services are the bluetooth Bluez services and not our code.

To explain, check the following behaviour where we start the BLENO Battery Service with the Bluetooth stack started:

root@halcyon:/opt/bleno/examples/battery-service# systemctl start bluetooth
root@halcyon:/opt/bleno/examples/battery-service# node main.js 
on -> stateChange: poweredOn
on -> advertisingStart: success
setServices: success

Using the Nordic nRF Connect Android App we can see the non working behaviour vs what we should expect from the Bleno Battery example:

BLE Scan Results

Pressing Connect we can see on Client that no service are provided. This is due to the fact that the desktop bluetooth is enabled):

Now let’s disable the bluetooth stack (which powers the BT adapter) and start again the Bleno Battery example:

root@pcortex:/opt/bleno/examples/battery-service# systemctl stop bluetooth
root@pcortex:/opt/bleno/examples/battery-service# node main.js 

Example hangs in here, because BT adapter is disabled/off

^Croot@pcortex:/opt/bleno/examples/battery-service# btmgmt power on
hci0 class of device changed: 0x00010c
hci0 Set Powered complete, settings: powered bondable ssp br/edr le secure-conn 
root@pcortex:/opt/bleno/examples/battery-service# node main.js 
on -> stateChange: poweredOn
on -> advertisingStart: success
setServices: success

And now if we scan again and connect to the Battery example with our mobile phone through the Nordic application we have:

It works now!

We can confirm that because on the file battery-service.js the service identifier is defined:

function BatteryService() {
  BatteryService.super_.call(this, {
      //uuid: '180F',
      uuid: 'ff51b30e-d7e2-4d93-8842-a7c4a57dfb07',
      characteristics: [
          new BatteryLevelCharacteristic()
      ]
  });
}

and it is the same detected by the Android application.

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CentoOS 7 on Virtual Box

These are some tips and information for configuring CentoOS 7 when running on VirtualBox, namely how to install the Virtual Box Extensions.

Checking the network

After installing we should check if we have connectivity namely if the network interface is up or not.

We can configure the network interface has NAT, which will use an internal DHCP server, but this means that the machine will not be accessible without some kind of port forwarding, or we can configure the interface in BRIDGE mode, which means that the machine will behave as the network interface is directly connected to the physical network. In this case an external DHCP server must be available to provide the interface address or we need to provide a static address.

In any case, I normally use the BRIDGE mode with an external DHCP server.

If by any chance the interface is up but has no address, check the network configuration file located in:

/etc/sysconfig/network-scripts/

If our interface is, as in this example, enp0s3 we should edit the file on the above directory named ifcfg-enp0s3 and change the entry (probably at the end of the file) from ONBOOT=no to ONBOOT=yes and reboot. (Note: Not always I needed to do this)

At the end the command ip a should show an active interface:

[root@localhost ~]# ip a
1: lo:  mtu 65536 qdisc noqueue state UNKNOWN qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: enp0s3:  mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 08:00:27:55:35:7b brd ff:ff:ff:ff:ff:ff
    inet 10.191.0.75/22 brd 10.191.0.255 scope global dynamic enp0s3
       valid_lft 598748sec preferred_lft 598748sec

Updating the system:
Before we are able to install the Virtual Box extensions we should first fully update the system and install some required packages:

yum upgrade
yum install bzip2
yum groupinstall "Development Tools"
yum install "Kernel-devel-uname-r == $(uname -r)"

Installing the guest additions:

After these per-requisites are installed we should go to the Virtual Box menu and Select Devices->Insert Guest Additions CD Image.

Selection_212

Always as the user root, we can do now two things, mount the CDROM on the directory /mnt or on a created subdirectory on /mnt. Let’s do the later:

[root@localhost ~]# cd /mnt
[root@localhost mnt]# mkdir cdrom
[root@localhost mnt]# mount -r /dev/cdrom /mnt/cdrom
[root@localhost mnt]# ls cdrom
32Bit  64Bit  AUTORUN.INF  autorun.sh  cert  OS2  runasroot.sh  VBoxLinuxAdditions.run  VBoxSolarisAdditions.pkg  VBoxWindowsAdditions-amd64.exe  VBoxWindowsAdditions.exe  VBoxWindowsAdditions-x86.exe

We can now install the additions:

[root@localhost mnt]# cd /mnt/cdrom
root@localhost cdrom]# ./VBoxLinuxAdditions.run 
Verifying archive integrity... All good.
Uncompressing VirtualBox 5.1.22 Guest Additions for Linux...........
VirtualBox Guest Additions installer
Removing installed version 5.1.22 of VirtualBox Guest Additions...
Copying additional installer modules ...
Installing additional modules ...
vboxadd.sh: Starting the VirtualBox Guest Additions.
[root@localhost cdrom]# 

It should work without any issues. We can now check if the Virtual Box Guest additions modules are running:

[root@localhost cdrom]# lsmod | grep vbox
vboxsf                 39741  0 
vboxguest             297360  2 vboxsf
[root@localhost cdrom]# 

Success!

Mounting the shared folders
We are now able to mount the shared folders that we define on the virtual box machine configuration.

For example let’s create the following share:
First select Devices->Shared Folders->Shared Folder Settings

Selection_213

And then add a share:
Selection_214

Two important things: The share name is the name that will be used on the mount command. And if the Make Permanent tick box is not selected, the share will be lost on reboot.

So we now can do the following to mount the shared folder:

[root@localhost mnt]# mkdir HostOpt
[root@localhost mnt]# mount -t vboxsf VBOXShare /mnt/HostOpt/
/sbin/mount.vboxsf: mounting failed with the error: Protocol error
[root@localhost mnt]# mount -t vboxsf VBOXShare /mnt/HostOpt
/sbin/mount.vboxsf: mounting failed with the error: Protocol error
[root@localhost mnt]# mount -t vboxsf VBOXShare /mnt/HostOpt

The can happen at least because of two reasons:
First: The share name is invalid. In this case the share name is VBOXShare, but vboxshare can also be used
Second: The configuration is not yet valid or applied (Pressing ok on the create share window).

And that’s it.

Setting up a Grafana Dashboard using Node-Red and InfluxDB – Part 4: Installing Grafana and configuring

Our software stack installation ends with configuring and installing Grafana. Ubuntu installation instructions are at this Grafana documentation link..

Installation is as easy as to download and install the latest Grafana dashboard version:

root@server:~# wget https://grafanarel.s3.amazonaws.com/builds/grafana_4.1.2-1486989747_amd64.deb
root@server:~# sudo dpkg -i grafana_4.1.2-1486989747_amd64.deb

In my case, the above instructions where enough to install successfully the software.

After installing if we will access the Dashboard through a reverse proxy, check out my previous post to configure correctly the Grafana server: Grafana Reverse Proxy

We can now start the Grafana server but if the server is exposed to the public internet the first thing to do is to change the default admin user password to something safe, or better yet, create a new admin user with a strong password and delete the admin default account.

We should press the top left icon, choose admin and then Global users. We can now select the Admin user and change the default password:

Here we also can create a new admin account, which is my recommendation.

Data source configuration:

Dashboard data provides from data sources that we configure on  Grafana. We can configure several data sources that we will used to fetch data to feed to our dashboards and graphs.

In our case we will configure a single InfluxDB datasource. Note that we didn’t defined any authentication for the InfluxDB server, so no access credentials are needed yet, but we should set ones as soon as possible.

Since Grafana and InfluxDB are running on the same server we use the base URL http://localhost:8086. Make sure that the connection type is set as proxy.

After setting the datasource name and datasource database, press Save & Test and it should report success.

Initial Dashboard configuration

We are now able to create a basic first dashboard by building some charts/graphs based on the previous created data source.

Press the New Dashboard button to create a new dashboard. In case that you don’t have a screen as the above screen shot, just press the top left Grafana Icon, select Dashboards and then New.

The following screen should appear where we can add graphical panels to show our data. We should the way that we want to show our data, by selecting the Graph type. The selected graph type should reflect immediately on the panel below. To edit the panel source data we should press the panel title and a pop-up window will appear, and then we press Edit.

We are now able to edit the associated queries that will fill the panel with data. Associated with the panel we can have multiple queries for the source data. In the default case a default query named A is already set up. We just need to change our measurement field to the correct one, which in our case could be Temperature or heap, based on the previous post (InfluxDB data configuration)

.

We need now to press the Select Measurement and a drop down box with the available measurement should appear. We select the one that we want and data should now appear on the above graph.

From now on is just a bit of perfecting things out like giving a sound name to the panel in the General tab and at the end pressing the Save icon on the top of the screen.

Setting up a Grafana Dashboard using Node-Red and InfluxDB – Part 3: Single point of access – Reverse proxy the services with nginx

Since we will be running a lot of services, each running on its own port, the following configuration, is optional, but allows to access all services through the same entry point by using Nginx server as a reverse proxy to Node-Red, Node-Red UI/Dashboard, Node-Red Worldmap and Grafana.

With this configuration the base URL is always the same without any appended ports, and the only thing that changes are the URL path:

http://server/nodered
http://server/nodered/worldmap
http://server/grafana

To allow this we install and configure Nginx:

apt-get install nginx

The configuration files will reside in /etc/nginx directory. Under that directory there are two directories: sites-available and sites-enable where the later normally contains a link to configuration files located at sites-available.
At that directory there is a file named default that defines the default web site configuration used by Nginx. This is the file where we will add the reverse proxy directives.

Reverse proxy for Node-Red and Node-Red Contrib Worldmap
For setting up the reverse proxy for Node-Red we must first change the base URL for Node Red from / (root) to something else that we can map the reverse proxy.

For this we will need to edit the settings.js file located on the .node-red directory on the home path of the user running Node-Red.

We need to uncomment and change the entry httpRoot to point to our new base URL.

   httpRoot: '/nodered',

Don’t forget the trailing comma.

We need to restart now Node-Red and it should be accessible at the URL http://server:1880/nodered instead of http://server:1880/.

To configure Nginx, we edit the file default at /etc/nginx/sites-available and add the following section:


        location  /nodered {
                proxy_set_header Host $http_host;
                proxy_set_header X-Real-IP $remote_addr;
                proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                proxy_set_header X-Forwarded-Proto $scheme;
                proxy_http_version 1.1;
                proxy_set_header Upgrade $http_upgrade;
                proxy_set_header Connection "upgrade";
                proxy_pass "http://127.0.0.1:1880";
        }

        location /socket.io {
                proxy_set_header Host $http_host;
                proxy_set_header X-Real-IP $remote_addr;
                proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                proxy_set_header X-Forwarded-Proto $scheme;
                proxy_http_version 1.1;
                proxy_set_header Upgrade $http_upgrade;
                proxy_set_header Connection "upgrade";
                proxy_pass "http://127.0.0.1:1880";

        }

Note the following: The first location defines the reverse proxy URL /nodered to be served by the backend server http://127.0.0.1:1880. The incoming path, /nodered, will be passed to the backend server URL /nodered, since paths are passed directly. No need to add the /nodered path to the backend server definition.
Also I’m using the 127.0.0.1 address instead of localhost to avoid the IPv6 mapping to the localhost. In this way I’m sure that IPv4 will be used.

The location mapping for /nodered will make all the functionality of node red to work as it should at the base url /nodered. But some nodes, like node-red-contrib-worldmap will request to the proxy server ignoring the node-red base root map. Hence the /socket.io mapping. It will allow the worldmap nodes to work, but will stop this mapping to be used for something else.

Reverse proxy for Grafana

Setting up the reverse proxy for Grafana we can, and should use the following documentation: Grafana Reverse Poxy. For me the following configuration worked:

First edit the [server] section on the Grafana configuration file grafana.ini located at /etc/grafana.

Uncomment and edit the following lines:

[server]
# Protocol (http or https)
protocol = http

# The ip address to bind to, empty will bind to all interfaces
;http_addr =

# The http port  to use
http_port = 3000

# The public facing domain name used to access grafana from a browser
domain = server.domain.com

# Redirect to correct domain if host header does not match domain
# Prevents DNS rebinding attacks
;enforce_domain = false

# The full public facing url you use in browser, used for redirects and emails
# If you use reverse proxy and sub path specify full url (with sub path)
root_url = http://server.domain.com/grafana/

Note the ending slash at the root_url. The same applies to the Nginx configuration

The files for the Nginx configuration are the same as the above configuration for reverse proxy.

We just need to add the following section after the previous location directives:

        location /grafana/ {
                proxy_pass http://localhost:3000/;
        }

We should now restart nginx to refresh the configuration, and all should be working as it should by accessing the Grafana dashboard at http://server.domain.com/grafana

Setting up a Grafana Dashboard using Node-Red and InfluxDB – Part 2: Database configuration and data collection

On the previous post we’ve installed and the base software for our Grafana based dash board.

We need now to configure our InfluxDB database and Node Red to start collecting data.

Configuring InfluxDB:
Detailed instructions for configuring an InfluxDB database are on this InfluxDB documentation link..

The main concepts that we need to be aware when using the InfluxDB is that record of data has a time stamp, a set of tags and a measured value. This allows, for example to create a value named Temperature and tag it depending on the source sensor:

Temperature: Value=22.1 , Sensor=Kitchen
Temperature: Value=21.9 , Sensor=Room1

This allows to process all the data or only process data based on a certain tag or tags. Values and tags can be created on the fly without previously define them, which is a bit different from standard RDBMS engines.

Creating an InfluxDB database:
To create the database, we need to access the machine hosting the InfluxDB server and execute the command influx:

odroid@odroid:~$ influx
Connected to http://localhost:8086 version 1.2.0
InfluxDB shell version: 1.2.0
> create database SensorData
> show databases
name: databases
name
----
_internal
SensorData

> 

Now we have our database created and I’ve named SensorData. To make an example with the above temperature data we can do the following:

> insert Temperature,Sensor=kitchen value=22.1
ERR: {"error":"database is required"}

Note: error may be due to not setting a database or retention policy.
Please set a database with the command "use " or
INSERT INTO . 
> use SensorData
Using database SensorData
> 

As we can see we need first to select the database where we are going to insert data with the command use SensorData:

> use SensorData
Using database SensorData
> insert Temperature, Sensor=kitchen value=22.1
ERR: {"error":"unable to parse 'Temperature, Sensor=kitchen value=22.1': missing tag key"}

> insert Temperature,Sensor=kitchen value=22.1
> insert Temperature,Sensor=Room1 value=21.9
> select * from Temperature
name: Temperature
time                Sensor  value
----                ------  -----
1487939008959909164 kitchen 22.1
1487939056354678353 Room1   21.9

Note that we can’t use spaces between the Measure name and the tags. The correct syntax is as follows:

 insert MeasureName,tag1=t1,tag2=t2,...   value1=val1,value2=val2,value3=val3,....

Also note that no DDL (data definition language) was used to create the tags or the measured value, we’ve just inserted data for our measurement with the our tags and value(s) without the need of previously define the schema.

Configuring Node-Red
Since we now have a database we can configure the InfluxDB Node Red nodes to store data onto the database:

There are two types of InfluxDB nodes, one that has an Input and Output and other that only has Input. The former is for making queries to the database where we provide on the input node the query, and on the output the results are returned. The later is for storing data only onto the database.
For both nodes we need to configure an InfluxDB server:

InfluxDB Server Configuration

We need to press the Pen icon right next to the server to add or reconfigure a new InfluxDB server:

InfluxDB server

A set of credentials are required, but since I’ve yet configured security, we can just put admin/admin as username and password. In a real deployment we must activate security.

From now on it is rather simple. Referring to InfluxDB node configuration screenshot (Not the InfluxDB server configuration) we have a configuration field named Measurement. This is our measure name that we associate a value. Picking up on the above example with the Insert command it will be Temperature, for example.

Now if the msg.payload provided has input to the node is a single value, let’s say 21, this is equivalent to do:

Insert Temperature value=12

We other formats for msg.payload that allows to associate tags and measures. Just check the Info tab for the node.

Simple example:

The following flow shows a simple example of a value received through MQTT, in this case the free heap from one of my ESP8266 and its storage in InfluxDB:

Sample Flow

[{"id":"20bec5de.8881c2","type":"mqtt in","z":"ced40abb.3c92e","name":"Heap","topic":"/outbox/ESP12DASH/Heap","qos":"2","broker":"2a552b3c.de8d2c","x":83.16668701171875,"y":206.41668701171875,"wires":[["e0d9c912.8c57f8","876fb151.6f2fa"]]},{"id":"876fb151.6f2fa","type":"debug","z":"ced40abb.3c92e","name":"","active":true,"console":"false","complete":"false","x":408.5,"y":177,"wires":[]},{"id":"e0d9c912.8c57f8","type":"influxdb out","z":"ced40abb.3c92e","influxdb":"bbd62a93.1a7108","name":"","measurement":"heap","x":446.1666717529297,"y":224.58335876464844,"wires":[]},{"id":"2a552b3c.de8d2c","type":"mqtt-broker","broker":"192.168.1.17","port":"1883","clientid":"node-red","usetls":false,"verifyservercert":true,"compatmode":true,"keepalive":15,"cleansession":true,"willQos":"0","birthQos":"0"},{"id":"bbd62a93.1a7108","type":"influxdb","z":"","hostname":"127.0.0.1","port":"8086","protocol":"http","database":"SensorData","name":"ODroid InfluxDB"}]

We can see with this flow the data stored in InfluxDB:

> select * from heap;
name: heap
time                value
----                -----
1487946319638000000 41600
1487946440913000000 41600
1487946562206000000 41600
1487946683474000000 41600
1487946804751000000 41600
1487946926061000000 41600
1487947047309000000 41616
1487947168594000000 41600

Now we have data that we can graph with Grafana, subject of my next posts.

Setting up a Grafana Dashboard using Node-Red and InfluxDB – Part 1: Installing

A more or less standard software stack used for control, processing and displaying data, has emerged that is almost used by everyone when hacking around on Arduinos, ESP8266, Raspeberry Pi’s and other plethora of devices. This “standard” software stack basically always includes the MQTT protocol, some sort of Web based services, Node-Red and several different cloud based services like Thingspeak, PubNub and so on. For displaying data locally, solutions like Freeboard and Node-Red UI are a great resources, but they only shows current data/status, and has no easy way to see historical data.

So on this post I’ll document a software stack based on Node-Red, InfluxDB and Graphana that I use to store and display data from sensors that I have around while keeping and be able to display historical memory of data. The key asset here is the specialized time-series database InfluxDB that keeps data stored and allows fast retrieval based on time-stamps: 5 minutes ago, the last 7 days, and so on. InfluxDB is not the only Time-Series database that is available, but it integrates directly with Grafana the software that allows the building of dashboards based on stored data.

I’m running an older version of InfluxDB on my ARM based Odroid server, since a long time ago, ARM based builds of InfluxDB and Grafana where not available. This is now not the case, but InfluxDB and Grafana have ARM based builds so we can use them on Raspberry PI and Odroid ARM based boards.

So let’s start:

Setting up Node-Red with InfluxDB
I’ll not detail the Node-Red installation itself since it is already documented thoroughly everywhere. To install the supporting nodes for InfluxDB we need to install the package node-red-contrib-influxdb

cd ~/.node-red
npm install  node-red-contrib-influxdb

We should now restart Node-red to assume/detect the new nodes.

Node Red InfluxDB nodes

Installing InfluxDB
We can go to the InfluxDB downloads page and follow the installation instructions for our platform. In my case I need the ARM build to be used on Odroid.

cd ~
wget https://dl.influxdata.com/influxdb/releases/influxdb-1.2.0_linux_armhf.tar.gz
tar xvzf influxdb-1.2.0_linux_armhf.tar.gz

The InfluxDB engine is now decompressed in the newly created directory influxdb-1.2.0-1. Inside this directory there are the directories that should be copied to the system directories /etc, /usr and /var:

sudo -s
cd /home/odroid/influxdb-1.2.0-1

Copy the files to the right location. I’ve added the -i switch just to make sure that I don’t overwrite nothing.

root@odroid:~/influxdb-1.2.0-1# cp -ir etc/ /etc
root@odroid:~/influxdb-1.2.0-1# cp -ir usr/* /usr
root@odroid:~/influxdb-1.2.0-1# cp -ir var/* /var

We need now to create the influxdb user and group:

root@odroid:~/influxdb-1.2.0-1# groupadd influxdb
root@odroid:~/influxdb-1.2.0-1# useradd -M -s /bin/false -d /var/lib/influxdb -G influxdb influxdb

We need now to change permissions on /var/lib/influxdb:

cd /var/lib
chown influxdb:influxdb influxdb

We can now set up the automatic start up script. On the directory /usr/lib/influxdb/scripts there are scripts for the systemctl based Linux versions and init.d based versions that is my case. So all I have to do is to copy the init.sh script from that directory to the /etc/init.d and link it to my run level:

root@odroid:~# cd /etc/init.d
root@odroid:/etc/init.d# cp /usr/lib/influxdb/scripts/init.sh influxdb
root@odroid:/etc/init.d# runlevel
 N 2
root@odroid:/etc/init.d# cd /etc/rc2.d
root@odroid:/etc/init.d# ln -s /etc/init.d/influxdb S90influxdb

And that’s it. We can now start the database with the command /etc/init.d/influxdb start

root@odroid:~# /etc/init.d/influxdb start
Starting influxdb...
influxdb process was started [ OK ]

We can see the influxdb logs at /var/log/influxdb and start using it through the command line client influx:

root@odroid:~# influx
Connected to http://localhost:8086 version 1.2.0
InfluxDB shell version: 1.2.0
> show databases
name: databases
name
----
_internal

> 

Installing Grafana
We need now to download Grafana. In my case for Odroid since it is an ARMv7 based processor, no release/binary is available.
But a ARM builds are available on this GitHub Repository: https://github.com/fg2it/grafana-on-raspberry for both the Raspberry Pi and other ARM based computer boards, but only for Debian/Ubuntu based OS’s. Just click on download button on the description for the ARMv7 based build and at the end of the next page a download link should be available:

odroid@odroid:~$ wget https://bintray.com/fg2it/deb/download_file?file_path=main%2Fg%2Fgrafana_4.1.2-1487023783_armhf.deb -O grafana.deb

And install:

root@odroid:~# dpkg -i grafana.deb
Selecting previously unselected package grafana.
(Reading database ... 164576 files and directories currently installed.)
Preparing to unpack grafana.deb ...
Unpacking grafana (4.1.2-1487023783) ...
Setting up grafana (4.1.2-1487023783) ...
Installing new version of config file /etc/default/grafana-server ...
Installing new version of config file /etc/grafana/grafana.ini ...
Installing new version of config file /etc/grafana/ldap.toml ...
Installing new version of config file /etc/init.d/grafana-server ...
Installing new version of config file /usr/lib/systemd/system/grafana-server.service ...

Set the automatic startup at boot:

root@odroid:~# ln -s /etc/init.d/grafana-server /etc/rc2.d/S91grafana-server

And we can now start the server:

root@odroid:~# /etc/init.d/grafana-server start
 * Starting Grafana Server    [ OK ] 
root@odroid:~# 

We can now access the server at the address: http://server:3000/ where server is the IP or DNS name of our ODroid or RPi.

Conclusion:
This ends the installation part for the base software.

The following steps are:

  • Create the Influx databases –
  • Receive data from sensors/devices and store it on the previously created database
  • Configure and create Grafana data sources and dashboards
  • Add some plugins to Grafana

Cloud based deployment for IOT devices

Following up on my previous post Cloud based CI with Platformio, after we have the build output from the Continuous Integration process, we are able now to deploy to our devices.

This last deploy phase of the cycle Develop, CI, Deliver using Cloud infrastructure, only makes sense to devices that are powerful enough to have permanent or periodic network connectivity and have no problems or limitations with power usage, bandwidth, are in range and are able to remotely be updated.

In reality this means that most low power devices, devices that use LPWAN technologies like LoraWan or SigFox, devices that are sleeping most of the time and are battery powered are not able to be easily updated. For these cases the only solution is really out of band management by upgrading locally the device.

So the scope of this post is just to simply build a cloud based process to allow ESP8266 devices to get update firmware from the CI output. On it’s simplest form all we need is to create a web server, make the firmware available at the server and provide the URL for OTA updates to the ESP8266 that use the HTTP updater.

One can already use from the squix blog the PHP file to be deployed on PHP enabled web server that delivers the latest builds for devices requesting over the air updates.

Openshift PaaS Cloud Platform

The simplest way of making the Squix PHP page available on the cloud is to use the great Platform as a Service Openshift by RedHat. The free tier allows to have three applications (gears) available and the sign up is free. At sign up time we need to name our own domain suffix so that, for example I choose primal I’ll have URL’s such as application-primal.rhcloud.com.

Openshift offers a series of pre-configured applications ready to be deployed such NodeJs, Java, Python and PHP.

Openshift preconfigured platforms

So after sign up, all we need is to create a new application based on the PHP 5.4 template, give it an URL (it can be the default PHP), and that’s it: we have our PHP enabled web server.

Deploying code to Openshift

To deploy code to Openshift we use the Git tool for manipulating our application repository on the PaaS cloud platform.

So we must first clone our repository locally, modify it and then upload the changes.

For obtaining the repository URL and connection details, we must first setup our local machine with the rhc command line tool and upload our public SSH key to the Openshift servers:

 [pcortex@pcortex:~]$ gem install rhc

If the gem tool is not available, first install Ruby (sudo pacman -S ruby).

We then setup the rhc tool with the command rhc setup. Complete details here.

The command rhc apps should list now our Openshift applications:

[pcortex@pcortex:~]$ rhc apps
nodejs @ http://nodejs-primal.rhcloud.com/ (uuid: 9a72d50252d09a72d5)
-----------------------------------------------------------------------------
  Domain:     primal
  Created:    Aug 26  3:43 PM
  Gears:      1 (defaults to small)
  Git URL:    ssh://9a72d50252d09a72d5@nodejs-primal.rhcloud.com/~/git/nodejs.git/
  SSH:        9a72d50252d09a72d5@nodejs-primal.rhcloud.com
  Deployment: auto (on git push)

  nodejs-0.10 (Node.js 0.10) 
----------------------------             
    Gears: 1 small 
                    
php @ http://php-primal.rhcloud.com/ (uuid: c0c157c41271b559e66) 
-----------------------------------------------------------------------                    
  Domain:     primal          
  Created:    12:16 PM  
  Gears:      1 (defaults to small) 
  Git URL:    ssh://c0c157c41271b559e66@php-primal.rhcloud.com/~/git/php.git/                
  SSH:        c0c157c41271b559e66@php-primal.rhcloud.com 
  Deployment: auto (on git push) 

  php-5.4 (PHP 5.4)
  -----------------
    Gears: 1 small

You have access to 2 applications.

We pull now the remote repository to our machine:

[pcortex@pcortex:~]$ mkdir Openshift
[pcortex@pcortex:~]$ cd Openshift
[pcortex@pcortex:Openshift]$ git clone ssh://c0c157c41271b559e66@php-primal.rhcloud.com/~/git/php.git/
[pcortex@pcortex:Openshift]$ cd php
[pcortex@pcortex:php]$ wget https://raw.githubusercontent.com/squix78/esp8266-ci-ota/master/server/firmware.php 

We should now change the PHP file so it uses our repository to bring up our firmware:

 <?php
    $githubApiUrl = "https://api.github.com/repos/squix78/esp8266-ci-ota/releases/latest";
    $ch = curl_init();

And then it’s just to commit the change to Openshift:

[pcortex@pcortex:php]$ git add firmware.php
[pcortex@pcortex:php]$ git commit -m "Added firmware.php file"
[pcortex@pcortex:php]$ git push
Counting objects: 3, done.
Delta compression using up to 8 threads.
Compressing objects: 100% (3/3), done.
Writing objects: 100% (3/3), 924 bytes | 0 bytes/s, done.
Total 3 (delta 0), reused 0 (delta 0)
remote: Stopping PHP 5.4 cartridge (Apache+mod_php)
remote: Waiting for stop to finish
remote: Waiting for stop to finish
remote: Building git ref 'master', commit a72403a
remote: Checking .openshift/pear.txt for PEAR dependency...
remote: Preparing build for deployment
remote: Deployment id is 8fdecb3f
remote: Activating deployment
remote: Starting PHP 5.4 cartridge (Apache+mod_php)
remote: Application directory "/" selected as DocumentRoot
remote: -------------------------
remote: Git Post-Receive Result: success
remote: Activation status: success
remote: Deployment completed with status: success
To ssh://php-primal.rhcloud.com/~/git/php.git/
   321e48b..a72403a  master -> master

And that’s it: the link for HTTP OTA is available at http://php-primal.rhcloud.com/firmware.php

Final notes:

With the above firmware.php file we can deliver a single firmware file to any device that calls the page.

But a better solution is needed if we want to:

– Deliver multiple firmware files to different devices
– Deliver different versions of firmware files, for example be able to lock a specific version to some devices
– Know which devices have updated
– Know which version of firmware the devices are running

and of course, add some security.