You can download from here a new version of the hbm2net T4 enabled. This version has a better command line parsing/error handling, and the configuration file to provide ( optionally ) is validate in order to report some meaningful error messages when needed. The utility is still command line, I suggest to use as a pre-build step in Visual Studio to generate your entities, or other code artifacts you need. Unzip the files in a folder, and launch hbm2net: 
As you can see, the configuration file is now optional. If omitted, the default internal template is used, that will generate the code artifacts for the entities. You can specify an output directory for the files ( if omitted will be the current directory ) and a flag, –ct, to avoid generating files if target files are newer than sources. This is to suppress the reload message box in Visual Studio every time you compile if you forget an entity file opened. Then you can specify hbm files, with wildcards too. So, the simplest command line to generate mappings is: 
If you want to use more generation step, you need to edit the configuration file, and inform hbm2net: hbm2net –config:myconfig.xml *.hbm.xml the configuration file is in the following format: 
The generator nodes can be multiple: each different generator can point to a different template in order to produce different code artifacts.The second parameter, output, is the file name you will generate. This is parsed internally by the T4 engine itself, so you can play your strategy in combining the file name having the clazz object, an instance of ClassMapping representing the current hbm fragment. The presented parameter produces a file called <classname>.generated.cs, and is the default behavior. Please note the template is specified as res://xxxx: this means to lookup the template internally. You can specify a template with a regular path as well, plus, you can use ~/xxx/yyy/mytemplate.tt to specify a path relative to the location where hbm2net is. A copy of hbm2net.tt is included in the zip however, so you can use as a starting point to create your generators. Some notes about T4. You will find the entire bible on that argument by starting here or here. I will show a snapshot of the hbm2net.tt of the current version: 
So, as you can see, very similar to the old asp stuff, not so different from NVelocity. The basic difference from other such engine is that we have reachable from inside the template any .NET type we can need. Furthermore, we can organize our generation with helpers by using the <#+ #> tags. Whit these tags we create a method inside the transformation class usable by the template itself. As an example, the <#=GetCommentForClass(clazz,1).TrimEnd()#> line call an helper function. In this case the body of this function is contained in the res://NHibernate.Tool.hbm2net.templates.common.tt file, but can be inlined with the template itself. Currently an object of type ClassMapping ( an internal hbm2net object used to represent a mapping fragment ) is passed to the template, as the field clazz. Sorry for the strange naming convention, I left something from the old original version, this maybe will change in future drops.
Esiste, o meglio esisteva un tool di code generation, per creare automaticamente le classi partendo dai file di mapping di NHibernate. Questo tool (hbm2net, presente in NHContrib ) è stato un po' dimenticato, per cui ho deciso di provare a riesumarlo, e di ammodernarlo un po' dandogli la possibilità di utilizzare il Text Template Transformation Toolkit (T4). Ho previsto un template interno per la semplice generazione delle classi di mapping, ma potenzialmente è possibile generare con facilità qualsiasi altro codice provvedendo un template esterno, ad esempio mascherine di UI, layer WCF etc etc.
La versione attuale è una pre-alfa, serve solo a dare un'idea, e a vedere se ci sono delle dipendenze in deploy di difficile gestione, non è ben chiaro a me se T4 sia presente in tutte le installazioni di Visual Studio.
Se volete provare il tool potete scaricarlo da qui. Per utilizzare il templating T4 dovete utilizzare la seguente linea di comand:
hbm2net --config=t4config.xml *.hbm.xml
è importante utilizzare il config indicato, altrimenti hbm2net defaulta sul render di NVelocity. Verra creata una cartella generated con i file sorgenti corrisondenti agli hbm.
Potete scaricare hbm2net da qui.
Per provare al volo è incluso nello zip anche un file di mapping simple1.hbm.xml.
Fatemi avere dei feedback!
Here you can find an Inflector ( a strategy to singularize, pluralize case convert and much more ) very useful in code generation. Supported languages are now English and spanish.
Microsoft released the Oslo May CTP, so I'm porting NHModeller to these new bits.
Porting the conole version was easy, just some error with the "null" in the AST graph, but nothing difficult. Fortunatelly NHModeller has a suite of about 100 test that really helped to catch all the problems.
The intellipad plugin is still work in progress,but finally I have something closed to the end:
The refactory was big, but the new plugin is simpler in code. The good news is that now is very easy to create a custom DSL editor, with squiggles and highligting. May be I will post an How to in the near future.
When an field name conflict with some database dialect keywords, NHibernate offer a syntax in the mapping to escape the identifier so that the mapping can behave properly: quote the identifier with the "`" sign.
Unfortunately the dialect implementer is not obliged to espose a list of keywords that needs to be escaped, so I decided to put something in the NHModeller syntax to achieve the same results.
This is the sample entity:
NHModel{
Entity From
{
@Select:int
@Count:int
Another:string(30)
} in @From
}
The sign @ forces the correct escape generation in the mapping:
<?xml version='1.0' ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="MyTest" namespace="MyTest.Entities">
<class name="From" table="`From`">
<id name="Id" column="Id" access="field.camelcase-underscore">
<generator class="native" />
</id>
<property name="Select" column="`Select`" type="System.Int32" not-null="true" />
<property name="Count" column="`Count`" type="System.Int32" not-null="true" />
<property name="Another" column="Another" type="String" not-null="true" length="30" />
</class>
</hibernate-mapping>
and will issue the correct db script ( ie MsSql2005 ):
if exists (select * from dbo.sysobjects where id = object_id(N'[From]') and OBJECTPROPERTY(id, N'IsUserTable') = 1) drop table [From];
create table [From] (
Id INT IDENTITY NOT NULL,
[Select] INT not null,
[Count] INT not null,
Another NVARCHAR(30) not null,
primary key (Id)
);
Well,
Some words about NHModeller. The basic idea is to have a central point where you define the entities of your model, that is not the Xml Mapping itself,neigther a databse schema nor the classes. The idea actually is not so different from modelling starting from the mapping files, but Xml is orrible to write, even with intellisense. NHModeller aim to make simpler writing a mapping, and generates the real one as one of the artifacts.
The project uses MGrammar as a parser generator for the DSL and Intellipad as the preferred editor. Both these comes from the Microsoft "Oslo" Project, still CTP at present.
The version I have developed till now deal correctly with:
- Native Keys ( implicit ) or any other simple key ( not composite )
- Property Mapping
- One-To-Many mappings
- Many-To-One mappings
- Many-To-Many Mappings
- Lazy / Eager fetching
- Subclass
I will post here a screenshot of the actual present version, running a just for fun blog model:
When a model is created, we have to launch the code generation. This is achieved by a console application, and intellipad is just spawning the process after asking the parameters.
The UI is not so good, due to my inexperience both in WPF and intellipad :(
After the generation we can have a glance to the artifacts generated we have:
-
Classes files
-
Xml for NHibernate mapping
-
And, expecialli thanks to NHibernate SchemaExport class, the DDL for our preferred DB ( at least if it is NH compliant )
The DDL is the most interesting part, expecially for me that I hate dealing with DB schemas... Here below an example of a DDL created for the blog model for SQL Server and Oracle.
Well, there is some more works, even if the generator till now let a newbie to start using NHibernate in minutes. We just need to compile the files in an assembly ( remember to put "Compile as" "Embedd Resource" for the hbm files), and start using the model.
Further Step-- Let use SchemaUpdate to modify a running model, deal with Components, Composite Key, Indices, One-to-One mapping.
The first test of NHModeller in intellipad:
A new "Mode" that show sintax coloring and run time error checking. This allow writing the DSL a little better than using the old friend Notepad.
I decided to stops developing a completely new GUI for NHModeller, but I would like to use Intellipad instead. Intellipad is a higly configurable editor that ships with Microsoft "Oslo" SDK ctp. So far I wrote an initial NHModeller command line version, and decided to start writing a plugin for Intellipad, or, better a "Mode". The task is not so difficult, thanks to these blogs:
Until now i found a little annoying thing: It is not possible to add a command to the MiniBuffer without directly modifying a script that in shipped with Intellipad. It would be really nice if some extension point were exposed, so that a new mode can add new commands to the minibuffer.
I'm working on a little project to satisfy my idea on creating a mapping for NHibernate describing the model entities in a notepad like fashion. The application I created leverage a new SDK from microsof, at present in CTP: Microsoft Oslo SDK.
The application starts from a very simple language, and starting from this creates the clsses, the hbm's and the database script ( Database script at the moment does not work... ;)
). The application deal with collections,references, subclassing, and many-to-many relationship.
Lets have a couple of screenshot, the first one about a relation Books-Authors...
This is the hbm (whit all the mapping in a single view ):
and this the mapping ( all the classes in a view):
A sample with subclassing ( a just for fun financial model )
Well, there is still some bugs, but the application really do what expected: a lot of boring code line autogenerated from an intuitive textual DSL.
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