THC Developers

THC - Developers

This page provides information for developers that write THC modules or that contribute to the evolution of THC.

Modules

Single Tcl file modules can directly be stored inside the folder modules. Modules that have multiple files should have a dedicated sub-folder that is placed inside modules.

For that modules are automatically loaded during initialization, the module Tcl names have to follow the following name convention: thc_<ModuleName>.tcl. The name of dedicated module sub-directories need to follow the following convention: thc_<ModuleName>.

Modules should use their dedicated namespace ::thc::[ModuleName]. Target interface modules allow accessing devices of a specific target via the following standard functions

	Description
Init <args>	Optional, allows initializing the target. This command is not automatically called, but needs to be called from the configuration file.
DeviceSetup <GetCmd>	Optional, is called when a new device is registered by <DefineDevice>. The 'get' command specification of the device is provided as argument to 'DeviceSetup'.
Get <GetCmdList>	Has to return the states of a list of devices. The 'get' commands for the device list is provided as argument. If a device state is not available 'Get' has to return an empty string ("").
Set <SetCmdList> <NewState>	Hast to set the states of a list of devices. the 'set' commands for the device list, as well as the new common state for all devices, are provided as arguments.

The 'get' and 'set' commands are derived from the command specifications provided to the thc::DefineDevice command. This is illustrated using the zWay module as example.

The configuration file contains an explicitly initialization of the z-way interface :

 thc::zWay::Init "http://localhost:8083"

The configuration file also registers 2 zWay devices :

 thc::DefineDevice LightLiving,state -get {thc_zWay "SwitchBinary 8.1"} \
                                    -set {thc_zWay "SwitchBinary 8.1"}
 thc::DefineDevice LightEntry,state -get {thc_zWay "SwitchBinary 9.2"} \
                                    -set {thc_zWay "SwitchBinary 9.2"}

The command thc::DefineDevice calls 'DeviceSetup' of the relevant module, providing as argument the 'get' command specification

 thc::zWay::DeviceSetup "SwitchBinary 8.1"
 thc::zWay::DeviceSetup "SwitchBinary 9.2"

When the states of all devices are updated every heartbeat, the 'Get' command of the module is called with a list of 'get' command specifications for all devices. The 'Get' command of the module has to return the list of the device states. In the following example the states of 2 devices is read.

 thc::zWay::Get {"SwitchBinary 8.1" "SwitchBinary 9.2"}

Devices states are defined with the [thc::Set] command, that accepts a list of devices to set

 thc::Set {LightLiving,state LightEntry,state} 1

The [thc::Set] command calls the Set command of the module, providing as argument the list of 'set' command specifications

 thc::zWay::Set {"SwitchBinary 8.1" "SwitchBinary 9.2"} 1