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Filter to apply a set of different scale and offset value to each asset and/or data point
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packages/Debian FOGL-2771 Add Coral package May 21, 2019
Description FOGL-2774 RPM packaging May 9, 2019
FindFogLAMP.cmake FOGL-2121 - Multiple scale factors in a single plugin Nov 28, 2018
Package Fix for x86_64 May 10, 2019
README.rst Update README.rst Jan 9, 2019
VERSION VERSION changed May 22, 2019
mkversion FOGL-2338 Support external VERSION file Jan 24, 2019
plugin.cpp Merge pull request #10 from foglamp/FOGL-2338 Jan 25, 2019
scale_set_filter.cpp FOGL-2266 Reconfigure for scale-set filter plugin Jan 9, 2019


FogLAMP "scale-set" C++ Filter plugin

Selectively apply a set of scale and offset values to data readings.

A JSON document configures the set of scale factors and offset values to add to readings. Each scale and offset value is associated with a regular expression whcih is matches against the asset name of the reading in the asset. Optionally a datapoint regular expression may also be given, this is used to match the datapoint within a matching asset.

Caution, if multiple regular expressions match a single asset and datapoint then all of the scale and offset values will be applied to the asset/datapoint.


The filter supports the following configuration items:

A switch to control if the filter should take effect or not

A JSON document which contains an array of scale factors to apply. Each element in the arary is a JSON object with the following properties:

A regular expression that should match the asset name
A regular expression that should match the data point within the asset
The scale factor to apply to the matching asset and data point
An offset value to apply to the matching asset and data point
{ "factors" : [
       "asset"     : "environment",
       "datapoint" : "temperature",
       "scale"     : 1.8,
       "offset"    : 32
       "asset"     : "environment",
       "datapoint" : "humidity",
       "scale"     : 0.1,
       "offset"    : 0


To build FogLAMP "scale-set" C++ filter plugin:

$ mkdir build
$ cd build
$ cmake ..
$ make
  • By default the FogLAMP develop package header files and libraries are expected to be located in /usr/include/foglamp and /usr/lib/foglamp
  • If FOGLAMP_ROOT env var is set and no -D options are set, the header files and libraries paths are pulled from the ones under the FOGLAMP_ROOT directory. Please note that you must first run 'make' in the FOGLAMP_ROOT directory.

You may also pass one or more of the following options to cmake to override this default behaviour:

  • FOGLAMP_SRC sets the path of a FogLAMP source tree
  • FOGLAMP_INCLUDE sets the path to FogLAMP header files
  • FOGLAMP_LIB sets the path to FogLAMP libraries
  • FOGLAMP_INSTALL sets the installation path of Random plugin
  • The FOGLAMP_INCLUDE option should point to a location where all the FogLAMP header files have been installed in a single directory.
  • The FOGLAMP_LIB option should point to a location where all the FogLAMP libraries have been installed in a single directory.
  • 'make install' target is defined only when FOGLAMP_INSTALL is set


  • no options

    $ cmake ..

  • no options and FOGLAMP_ROOT set

    $ export FOGLAMP_ROOT=/some_foglamp_setup

    $ cmake ..


    $ cmake -DFOGLAMP_SRC=/home/source/develop/FogLAMP ..


    $ cmake -DFOGLAMP_INCLUDE=/dev-package/include ..


    $ cmake -DFOGLAMP_LIB=/home/dev/package/lib ..


    $ cmake -DFOGLAMP_INSTALL=/home/source/develop/FogLAMP ..

    $ cmake -DFOGLAMP_INSTALL=/usr/local/foglamp ..

Packaging for 'scale-set' filter

This repo contains the scripts used to create a foglamp-filter-scale-set Debian package.

The make_deb script

Run the make_deb:

$ ./make_deb help
make_deb [help|clean|cleanall]
This script is used to create the Debian package of FoglAMP C++ 'scale-set' filter plugin
 help     - Display this help text
 clean    - Remove all the old versions saved in format .XXXX
 cleanall - Remove all the versions, including the last one

Building a Package

Finally, run the make_deb command:

$ ./make_deb
The package root directory is   : /home/ubuntu/source/foglamp-filter-scale-set
The FogLAMP required version    : >=1.4
The package will be built in    : /home/ubuntu/source/foglamp-filter-scale-set/packages/build
The architecture is set as      : x86_64
The package name is             : foglamp-filter-scale-set-1.0.0-x86_64

Populating the package and updating version file...Done.
Building the new package...
dpkg-deb: building package 'foglamp-filter-scale-set' in 'foglamp-filter-scale-set-1.0.0-x86_64.deb'.
Building Complete.

Cleaning the Package Folder

Use the clean option to remove all the old packages and the files used to make the package.

Use the cleanall option to remove all the packages and the files used to make the package.

You can’t perform that action at this time.