Introduction

XRoadProvider library is a collection of type providers that make easier the integration process for data exchange layer X-Road. Currently three different type providers are implemented:

  • XRoadProducer is generated type provider which offers type signatures for types and method call functionality for operations defined in producers service description.

  • XRoadServer is erased type provider that discovers available producer names from specified security server and offers their details inside development environment (legacy version that supports older X-Road security servers).

  • XRoadServer6 is erased type provider that discovers available producer names from specified security server and offers their details inside development environment (for X-Road security server version 6).

XRoadProvider library can be installed from NuGet:

PM> Install-Package XRoadProvider

About Type Providers

Since type providers are language specific feature of F# programming language, they can only be defined and set up in F# projects or scripts. Fortunately, it takes minimal effort to set things up and ready to be imported into other dependant projects that might already be in different .NET platform language, like C#.

A general definition for type providers is, that they work as F# compiler plugins, which transform some source of outside information that is presented in well defined form (like WSDL definition) to code that can be used by compiler for two primary purposes. First, compiler uses that information to provide metadata that can be used as intellisense in IDE-s and editors to provide signatures of types, methods, etc.; provide code complete information and more features that are common part of modern software development tools. Secondly, it uses that same information to compile that metadata into assembly which can be used as regular dependency that was interpreted from source information and written into code by some unknown developer.

Using this feature of F# language, this package interprets two sources of information to produce easier X-Road service development experience to software developers:

  • Using web service producer defined WSDL definition as source information it provides service interfaces and client logic to execute these operations over X-Road infrastucture. For that purpose the package defines XRoadProducer Type Provider.

  • Using X-Road security server meta services as source information it provides IDE experience for convenient browsing and exploration of services and producers that are available on X-Road platform. Read about XRoadServer6 Type Provider for more details and examples.

Using the package

F# language has two options to write executable code. You can create regular .NET assembly project (library, executable) compile it and the run it. Another, more lightweight, but as powerful option is to write F# script file and execute it in F# interactive.

Creating .NET project

To use this package in regular MSBuild project, create new F# project (library or executable, depending on needs). Then add reference to XRoadProvider NuGet package.

After adding a new source code file (with .fs file extension) or using the default Library1.fs file, replace the existing contents with following statement which imports the namespace that defines type provider types (open basically corresponds to using statement in C#).

open XRoad.Providers

Next step would be using particular type providers, which is described in previously referred guides.

Writing F# script

Inside Visual Studio create new F# script file (it has .fsx extension). Unzip this packages files in some known location for referencing from script. Replace contents of the script with following statements:

#load "/path/to/known/location/of/package/lib/net461/XRoadProvider.fsx"
open XRoad.Providers

The first line imports bootstrapper script which adds neccessary dependencies of the package, and second line, again, opens the namespace which has type provider definitions.

As with .NET project approach, next step is to continue with other guides to try out type providers. After completing the script, you can run it in F# interactive which basically means you can try out X-Road services in real time using the script you just wrote and modifying it as needed. This allows to try out X-Road services in minutes, without the need to build complex client application beforehand.