Scaffolding other types of files: What filename should I put in?

[doggy8088]

In the Scaffolding other types of files, you provided an T4 example, but not mentioned about the filename and where should I put it into. I don't know how to use this Mermaid T4 script.

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Document Details

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• ID: cae415b7-c0ea-4d96-9d17-7e7d3163c09d
• Version Independent ID: cae415b7-c0ea-4d96-9d17-7e7d3163c09d
• Content: Custom Reverse Engineering Templates - EF Core
• Content Source: entity-framework/core/managing-schemas/scaffolding/templates.md
• Product: entity-framework
• Technology: entity-framework-core
• GitHub Login: @bricelam
• Microsoft Alias: avickers

[bricelam]

The mermaid script is intended to be used as a custom DbContext.t4. We should mention this in the article.

[doggy8088]

How to put two DbContext.t4 in the same project? I want to generate both the context and the mermaid file.

[bricelam]

You can't, but you can create a separate dummy project for the diagrams. Or just rename the files before generating.

[ErikEJ]

You can with EF Core Power Tools

[doggy8088]

@ErikEJ Does EFCPT can handle multiple T4 templates other than DbContext.t4 and EntityType.t4?

[doggy8088]

The mermaid sample from the doc seems not functional.

[ErikEJ]

@doggy8088 Yes, both the VS and CLI editions support that, as documented here

[ErikEJ]

The mermaid sample from the doc seems not functional.

A limitation in the MarkDown viewer?

[doggy8088]

The mermaid sample from the doc seems not functional.

A limitation in the MarkDown viewer?

No, it's a bug. I fixed as below:

<#@ output extension=".md" #>
<#@ assembly name="Microsoft.EntityFrameworkCore" #>
<#@ assembly name="Microsoft.EntityFrameworkCore.Relational" #>
<#@ assembly name="Microsoft.EntityFrameworkCore.Design" #>
<#@ parameter name="Model" type="Microsoft.EntityFrameworkCore.Metadata.IModel" #>
<#@ parameter name="Options" type="Microsoft.EntityFrameworkCore.Scaffolding.ModelCodeGenerationOptions" #>
<#@ import namespace="System.Linq" #>
<#@ import namespace="Microsoft.EntityFrameworkCore" #>
# <#= Options.ContextName #>

```mermaid
erDiagram
<#
    foreach (var entityType in Model.GetEntityTypes().Where(e => !e.IsSimpleManyToManyJoinEntityType()))
    {
#>
    <#= entityType.Name #> {
    }
<#
        foreach (var foreignKey in entityType.GetForeignKeys())
        {
#>
    <#= entityType.Name #> <#= foreignKey.IsUnique ? "|" : "}" #>o--<#= foreignKey.IsRequired ? "|" : "o" #>| <#= foreignKey.PrincipalEntityType.Name #> : "<#= foreignKey.GetConstraintName() #>"
<#
        }

        foreach (var skipNavigation in entityType.GetSkipNavigations().Where(n => n.IsLeftNavigation()))
        {
#>
    <#= entityType.Name #> }o--o{ <#= skipNavigation.TargetEntityType.Name #> : <#= skipNavigation.JoinEntityType.Name #>
<#
        }
    }
#>

![image](https://github.com/dotnet/EntityFramework.Docs/assets/88981/5cc46098-b708-4e34-8089-3a13fa0a2a57)

[ErikEJ]

Maybe a docs PR?

[doggy8088]

Maybe a docs PR?

Already done https://github.com/dotnet/EntityFramework.Docs/pull/4463

[doggy8088]

@doggy8088 Yes, both the VS and CLI editions support that, as documented here

@ErikEJ I put a Docs/CodeTemplates/EFCore/DbContext.t4 file. How can I let ContosoUniversityContext.md into Docs/ folder?

[ErikEJ]

How can I let ContosoUniversityContext.md into Docs/ folder?

@doggy8088 Currently the files generated by DbContext.t4 are placed in same location as DbContext.cs, but I think it could be changed to the Docs folder. Please create an issue in EF Core Power Tools repo and I will investigate.

[ErikEJ]

@doggy8088 I implemented a fix in the latest source, maybe you can test it from the latest master?