Watchdog

What is the gateway watchdog

The SENSEI Gateway Watchdog is a monitoring and control service for the SENSEI Gateway. It allows for remote starting, stoping and updating the gateway code and can report the version string and uptime of the currently running gateway binary.

Requirements

• Linux
• g++, make
• ​Sockets C++ library (Also included in lib/Sockets-2.3.7; make clean; make; make install)
• libxml2
• openssl, openssl-dev

Project Organization

The watchdog shares its code with the gateway implementation and can be found in the ​/gateway folder in the SVN.

• ​/bin executables
• ​/src Gateway and Watchdog Code
• ​/xml Location of resource descriptions
• ​/lib Sockets++ library
• ​/config Configuration files (unused)
• ​/log Log files (unused)

How to build it

The top-level Makefile will build everything with the following, which places the executables in ./bin. Note that the executables must be run from the root of the project as shown below.

make
./bin/watchdog

To clean everything do

make clean

To build the Sockets++ library

cd ./lib/Sockets-2.3.7
make clean
make
sudo make install

How to use it

The watchdog must be run from the root of the project

./bin/watchdog

Available command line options are: -p HTTPD port (default: 9000)
-s HTTPD hostname for inserting in resource desciption (default: localhost)
-d domain name inserted in resource description (default: example.com)
-w WSAN island name inserted in resource description (default: Example)
-f folder where the gateway binary can be found (default: ./)
-c gateway binary filename (default: sensei-gateway)
-cert ssl certificate filename, also enables https operation
-pass ssl certificate passphrase, necessary if the certificate file is encrypted

The SENSEI Gateway Watchdog server runs by default on port 9000. It exposes the following urls:

• /start - a POST request starts the gateway if not already started
• /stop - a POST request stops the gateway
• /update - a POST request with a form that has a 'file' field named 'code' updates the gateway binary, a 'text' field named 'version' can also be sent as the version string for the newly uploaded binary, otherwise version string will be taken from the uploaded file
• /uptime - a GET request returns the uptime of the gateway in seconds or -1 if the gateway is not started
• /version - a GET request returns the gateway version string, if one is available.

For the /start, /stop and /uptime urls GET requests are also accepted. They return an HTML page that allows easy access to the operations from a browser.