The Module Context

In the context of the C++ Micro Services library, we will call all supported "shared library" types (DLL, DSO, DyLib, etc.) uniformly a module. A module accesses the C++ Micro Services API via a ModuleContext object. While multiple modules could use the same ModuleContext, it is highly recommended that each module gets its own (this will enable module specific service usage tracking and also allows the C++ Micro Services framework to properly cleanup resources after a module has been unloaded).

Creating a ModuleContext

To create a ModuleContext object for a specific library, you have two options. If your project uses CMake as the build system, use the supplied usFunctionGenerateModuleInit CMake function to automatically create a source file and add it to your module's sources:

set(module_srcs )
usFunctionGenerateModuleInit(module_srcs
                             NAME "My Module"
                             LIBRARY_NAME "mylibname"
                            )
add_library(mylib ${module_srcs})

If you do not use CMake, you have to add a call to the macro US_INITIALIZE_MODULE in one of the source files of your module:

#include <usModuleInitialization.h>

US_INITIALIZE_MODULE("My Module", "mylibname")

Getting a ModuleContext

To retrieve the module specific ModuleContext object from anywhere in your module, use the GetModuleContext function:

#include <usGetModuleContext.h>
#include <usModule.h>
#include <usModuleContext.h>

US_USE_NAMESPACE

void RetrieveModuleContext()
{
  ModuleContext* context = GetModuleContext();
  Module* module = context->GetModule();
  std::cout << "Module name: " << module->GetName() << " [id: " << module->GetModuleId() << "]\n";
}

Please note that the call to GetModuleContext will fail if you did not create a module specific context.