• Overview
  • Architecture
  • Getting Started
    • DMBridge Executable
    • UWP
    • Non-UWP
• Other Documentation
• Open-Source Libraries

Device Management (DM) Bridge allows developers to locally configure and monitor IoT devices. This project exposes APIs for UWP, and non-UWP applications to easily perform device management. UWP applications can use WinRT APIs, and non-UWP applications can directly call the Rpc API.

DM Bridge is split into 3 main projects:

• DMBridgeInterface defines the Rpc methods that DMBridge will implement, and that DMBridgeComponent will call.
• DMBridge is an NTService that runs as the SYSTEM account and runs an Rpc server, exposing the APIs defined in DMBridgeInterface.
• DMBridgeComponenet is a WinRT/C++ Component, and what can be built as a NuGet package. It provides projections for the Rpc API that DMBridge serves. This allows any UWP application to easily consume the API (UWP Example). Non-UWP applications can directly call the Rpc API exposed by DMBridge rather than going through this UWP-specific project (Non-UWP Example).

The below diagram illustrates how each project in this solution is involved for a UWP application.

• Visual Studio 15.9.6
• Windows SDK 10.0.17134.0

If an application calls a DM Bridge API while DMBridge.exe is not running, a COMException with the message the rpc server is unavailable will be thrown. Ensure DMBridge.exe is either installed and running as a service, or is running as Administrator using DMBridge.exe -console for testing purposes. For further documentation on how to use DMBridge.exe see the deploying DMBridge documentation.

The below is an example of how to use DMBridgeComponenet in a UWP C# application:

using DMBridgeComponent;

...

using (var serviceManager = new NTServiceBridge())
{
    int dhcpStatus = serviceManager.Query("dhcp");
}

For a more complete usage, including exception handling, see the included sample, or the UWP API documentation.

Non-UWP applications can directly call the Rpc methods that DMBridge serves. Below is a simple example of a c program using the DMBridgeRpcInterface project to call a DM Bridge API. The example below should:

• Link with Rpcrt4.lib.
• Reference DMBridgeRpcInterface or add the project to to the Includes Directory project variable.
• Add DMBridgeInterface_c.c, which is generated by the DMBridgeRpcInterface project.

#include "DMBridgeInterface_h.h"
#include <stdio.h>
#include <Rpc.h>

#define RPC_PROTOCOL_SEQUENCE L"ncalrpc"
#define RPC_ENDPOINT L"DmBridgeRpcEndpoint"

int wmain(int argc, wchar_t *argv[])
{
    /* Create the Rpc handle */
    RPC_WSTR stringBinding = nullptr;
    RPC_BINDING_HANDLE rpcHandle = nullptr;

    RpcStringBindingCompose(
                NULL,
                (RPC_WSTR)RPC_PROTOCOL_SEQUENCE,
                NULL,
                (RPC_WSTR)RPC_ENDPOINT,
                NULL,
                &stringBinding);
    RpcBindingFromStringBinding(stringBinding, &rpcHandle);
    RpcStringFree(&stringBinding);

    /* Call a DM Bridge API */
    int dhcpStatus;
    wchar_t* dhcpServiceName = const_cast<wchar_t*>(L"dhcp");
    HRESULT ret = ::QueryServiceRpc(rpcHandle, dhcpServiceName, &dhcpStatus);

    if (ret == S_OK)
    {
        // There were no errors
        printf("DHCP service status: %d", dhcpStatus);
    }

    /* Close the Rpc handle */
    RpcBindingFree(&rpcHandle);

    return 0;
}

/* These must be included for Rpc */
/******************************************************/
/*         MIDL allocate and free                     */
/******************************************************/
void __RPC_FAR * __RPC_USER midl_user_allocate(size_t len)
{
    return(malloc(len));
}

void __RPC_USER midl_user_free(void __RPC_FAR * ptr)
{
    free(ptr);
}

For a more complete usage, including exception handling, see DMBridgeComponent.

• Adding New API
• Building (including the NuGet package)
• Configuring
• Deploying
• UWP APIs

DM Bridge uses the following open-source libraries:

• jsoncpp: A C++ JSON parser under either the MIT License or Public Domain.