Extension MQTT Interface - read symbols by identifier

[StGoebel]

What is the issue?

When you want to get the variables of a TwinCAT project, always the whole variable list of the project is extracted.
Sometimes you just want to control a subset of all the variables. The issue is to provide a functionality, such that you can
mark with comments the variables you want to get and only those variables will be extracted.

What is the current application?

The module parsing_and_assignment contains the functions, that extract the variable list of the TwinCAT project. You provide
either a text file (*.GVL) containing the variables list or a an ADS connection to the corresponding function in
parsing_and_assignment (for example parsing_and_assignment.getADSVariables(gvl_file)) and the functions return
the variables categorized in a publish- and a subscribe-set.

How do we want to solve it?

To parsing_and_assignment the functions "getMarkedADSVariables" and "getMarkedADSvarsFromSymbols" will be added.
One function gets the marked variables from a text file, the other on directly from the ADS connection. The desired
variables have to be commented with "//#" in the TwinCAT project, the functions will then only extract the variables marked
with the respective comment.

[StGoebel]

Hi @ErnestoVivas, the functions are working!
Two points we should work on:

• the marker for identifying the symbol which should be published should not have to stand alone in the comment
• variables inside a structure should be considered