Visual Studio Extension

[christoneethling]

Hi there, I was just wondering if there was ever a consideration to make this tool a visual studio extension? What would you consider the pro's and cons of the alternative approaches? Thanks

[Drizin]

I've thought about that and sounds like a great idea for reaching a broader audience. But I wouldn't even know where to start. Do you have experience? Would you like to collaborate with a PR?

Right now there's basically CodegenCS which is a class library with helpers, and there's dotnet-codegencs which is a .NET global tool which can be invoked using any bat/cmd/ps1. What I have been doing (check this is just using PS1 scripts to invoke the global tool. In the second script you'll see I basically run codegencs run SimplePOCOGenerator.cs. Basically the run action of the tool will create a single-csfile csproj, add some standard references (like Newtonsoft), and run the csproj. There are some obvious flaws in this approach (e.g. how to reference other Nuget dependencies). I also made some experiments using pure Roslyn (in this source generator) but that's not much different.

I suppose the most intuitive/friendly approach for running a template would be something like:

• Define a file extension for codegencs scripts (e.g. .cgcs)
• Create a VS Custom Tool (aka Single-File Generator), associate it with our extension (like T4 templates do for TT files using TextTemplatingFilePreprocessor). This would let users to right-button and "Run custom extension".
• Create a VS Extension VSIX for Custom Item Template (automatically adding empty/sample cgcs templates to the project). Maybe connecting to Github to browse for a list of templates.
• Define some syntax (like csx files do) for declaring Nuget references in the .cgcs file
• Custom tool would compile the cgcs code (with the required dependencies)
• Custom tool would search for the entrypoint and invoke it.
• In order to allow generators to be very simple, if the entrypoint expects a CodegenContext we can provide that and after the execution we can save the output files nested under the .cgcs in Solution Explorer.
• For more elaborated scripts users could just create CodegenContext on their own. With C# top-level methods the scripts can be as simple as a few lines.

And for extracting a database schema it could also be based on Wizard-like VS extensions:

• Define an extension for dbschemas (e.g. .cgcsdbschema)
• Create a VS Extension VSIX for Custom Item Template with Wizard that would guide through connecting to a database and extracting the schema. Would also have to support right-button to refresh schema.
• Properties Window would show properties like Dbtype, ConnectionString.
• Possible the extension could also in the end offer some cgcs templates to be automatically added and associated to the schema

What are your thoughts? Do you have any opensource extensions that we could refer to?

[Rickrat]

The custom file extensions already sound like you str doing and also an easy way to learn the VS SDK. Enjoy it!

[Drizin]

@christoneethling @Rickrat I've just published the first draft for the VS extension.

Can you please test it?

• Please search for "CodegenCS" in Extensions menu, or download here.
• Add a file with CSX extension (check some examples here)
• Right-click and select "CodegenCS Run Template" - it should run the template
• Alternatively you can set "Custom Tool" to be "CodegenCS", and then the template will run automatically after each save.

If it works well please rate the extension with 5 stars and share with your friends.

[Drizin]

Did you have a chance to try the extension? I've just published v3.1 (for Visual Studio 2022 only).

One new cool stuff is dependency injection (that can load files - path is relative to the template:

public class MyTemplate
{
    void Main(ICodegenContext context, IModelFactory factory)
    {
        var model = factory.LoadModelFromFile<OpenApiDocument>("petstore-openapi3.json");
        foreach (var entity in model.Definitions)
            context[entity.Key + ".cs"].WriteLine(GenerateEntity(entity.Key, entity.Value));
    }
    FormattableString GenerateEntity(string definitionName, NJsonSchema.JsonSchema schema)
    {
        return $$"""
            namespace MyNamespace
            {
                public class {{definitionName}}
                {
                    // my properties...
                    {{ schema.Properties.Select(prop => GenerateProperty(prop)) }}
                }
            }
            """;
    }
    FormattableString GenerateProperty(KeyValuePair<string, NJsonSchema.JsonSchemaProperty> prop)
    {
        return $$"""
        xx
        """;
    }
}