Working with Code Generation

Owned by Vinaya Mayya
Last updated: Mar 20, 2024
12 min read

The Code Generation utility is a .NET 8 command-line application that has been integrated into the Ed-Fi ODS / API initdev process. Its responsibility is to generate C# classes, ORM mapping files for the core application, plus all profiles and extensions. It uses logic-less {{mustache}} templates that are embedded within the assembly to generate the files. The application depends on Castle Windsor for its container.

The code generation tool is located in the ODS repository under the folder Utilities\CodeGeneration.

Requirements

The following are required to build the application:

  • Visual Studio 2022 / JetBrains Rider 2021.3
  • .NET 8.0

Template Model

Template models generate an anonymous object to drive the mustache template. All template models implement the interface ITemplateModel, and these models are then installed into the container to be run.

To add a new template model:

  1. Create a new class in the TemplateModels namespace. 
  2. Utilize the Template Method Pattern and inherit from TemplateModelBase.
  3. Implement the BuildTemplateModel() method.
  4. Optionally, implement the Configure() method, if pre-processing is necessary.
  5. Optionally, add a Constructor for any dependencies to be injected.

The code below shows an example template model:

using System.Collections.Generic;
using System.Linq;
using EdFi.Ods.Common;
using EdFi.Ods.Xml.XmlShredding;

namespace EdFi.Ods.CodeGen.TemplateModels
{
    public class EdOrgReferenceDictionaryProvider : TemplateModelBase
    {
        private readonly IEdOrgReferenceDictionaryProvider _edOrgReferenceDictionaryProvider;

        public EdOrgReferenceDictionaryProvider(IEdOrgReferenceDictionaryProvider edOrgReferenceDictionaryProvider)
        {
            _edOrgReferenceDictionaryProvider = edOrgReferenceDictionaryProvider;
        }

        protected override object BuildTemplateModel()
        {
            IDictionary<string, IMapStep> metadata = _edOrgReferenceDictionaryProvider.GetDictionary();

            var edOrgReferences = metadata.Keys
                                          .Select(
                                               x => new
                                                    {
                                                        EdOrgReferenceType = x, EdOrgReferenceKey = metadata[x].GetXPath()[0]
                                                    })
                                          .ToArray();

            return new
                   {
                       NamespaceName = Namespaces.CodeGen.XmlShredding,
                       EdOrgReferences = edOrgReferences
                   };
        }
    }
}

Assembly Metadata

The utility introduces a new file within each assembly root folder that requires code generation, the assemblyMetadata.json file:

{
    "assemblyModelType": "standard",
    "assemblyMetadataFormatVersion": "1.0.0"
}
  • assemblyModelType maps the to the template set to generate.
  • assemblyMetadataFormateVersion is the semantic version of the file.

For backward compatibility, profiles and extensions are also picked up using conventions. This may be removed in the future.

Template Sets

Template Sets are a grouping of Template Models that are to be rendered. This grouping is stored in an embedded object named TemplateSets.json which contains an array of TemplateSet objects.

namespace EdFi.Ods.CodeGen.Models.Configuration
{
    public class TemplateSet
    {
        public string Name { get; set; }

        public string Driver { get; set; }

        public string OutputName { get; set; }

        public string OutputPath { get; set; }

        public override string ToString() => $@"
Name:        {Name}
Driver:      {Driver}
OutputName:  {OutputName}
OutputPath:  {OutputPath}
";
    }
}
  • Name is the name of the template.
  • Driver is the C# Template Model.
  • OutputName is the file name that is created.
  • OutputPath is the location within the assembly to which the file is written.

The listing below shows the TemplateSets.json contents:

{
  "standard": [
    {
      "Name": "InterchangeType",
      "Driver": "InterchangeType",
      "OutputName": "InterchangeType.generated.cs",
      "OutputPath": "BulkLoad\\InterchangeType.generated.cs"
    },
    {
      "Name": "DatabaseMetadata",
      "Driver": "DatabaseMetadataProvider",
      "OutputName": "DatabaseMetadata.generated.cs",
      "OutputPath": "ExceptionHandling\\DatabaseMetadata.generated.cs"
    },
    {
      "Name": "Entities",
      "Driver": "Entities",
      "OutputName": "Entities.generated.cs",
      "OutputPath": "Models\\Entities\\Entities.generated.cs"
    },
    {
      "Name": "EntitiesForQueries",
      "Driver": "EntitiesForQueries",
      "OutputName": "EntitiesForQueries.generated.cs",
      "OutputPath": "Models\\Entities\\EntitiesForQueries.generated.cs"
    },
    {
      "Name": "EntitiesForQueriesViews",
      "Driver": "EntitiesForQueriesViews",
      "OutputName": "EntitiesForQueriesViews.generated.cs",
      "OutputPath": "Models\\Entities\\EntitiesForQueriesViews.generated.cs"
    },
    {
      "Name": "EntityInterfaces",
      "Driver": "EntityInterfaces",
      "OutputName": "EntityInterfaces.generated.cs",
      "OutputPath": "Models\\Interfaces\\EntityInterfaces.generated.cs"
    },
    {
      "Name": "EntityRecordInterfaces",
      "Driver": "EntityRecordInterfaces",
      "OutputName": "EntityRecordInterfaces.generated.cs",
      "OutputPath": "Models\\Interfaces\\EntityRecordInterfaces.generated.cs"
    },
    {
      "Name": "EntityMapper",
      "Driver": "EntityMapper",
      "OutputName": "EntityMapper.generated.cs",
      "OutputPath": "Models\\Mappers\\EntityMapper.generated.cs"
    },
    {
      "Name": "CreateOrUpdatePipelines",
      "Driver": "CreateOrUpdatePipelines",
      "OutputName": "CreateOrUpdatePipelines.generated.cs",
      "OutputPath": "Pipelines\\CreateOrUpdatePipelines.generated.cs"
    },
    {
      "Name": "Controllers",
      "Driver": "Controllers",
      "OutputName": "Controllers.generated.cs",
      "OutputPath": "Controllers\\Controllers.generated.cs"
    },
    {
      "Name": "Requests",
      "Driver": "Requests",
      "OutputName": "Requests.generated.cs",
      "OutputPath": "Requests\\Requests.generated.cs"
    },
    {
      "Name": "Resources",
      "Driver": "Resources",
      "OutputName": "Resources.generated.cs",
      "OutputPath": "Resources\\Resources.generated.cs"
    },
    {
      "Name": "ResourceFactories",
      "Driver": "ResourceFactories",
      "OutputName": "ResourceFactories.generated.cs",
      "OutputPath": "XmlShredding\\ResourceFactories.generated.cs"
    }
  ],
  "standard.bulk": [
    {
      "Name": "AggregateLoaders",
      "Driver": "AggregateLoaders",
      "OutputName": "AggregateLoaders.generated.cs",
      "OutputPath": "Core\\Controllers\\Aggregates\\AggregateLoaders.generated.cs"
    },
    {
      "Name": "LoaderCollection",
      "Driver": "LoaderCollection",
      "OutputName": "LoaderCollection.generated.cs",
      "OutputPath": "Core\\Controllers\\Aggregates\\LoaderCollection.generated.cs"
    }
  ],
  "standard.nhibernate": [
    {
      "Name": "EntityOrmMappings",
      "Driver": "EntityOrmMappings",
      "OutputName": "EntityOrmMappings.generated.hbm.xml",
      "OutputPath": "EntityOrmMappings.generated.hbm.xml"
    },
    {
      "Name": "EntityOrmMappings",
      "Driver": "EntityOrmMappingsForQueries",
      "OutputName": "EntityOrmMappingsForQueries.generated.hbm.xml",
      "OutputPath": "EntityOrmMappingsForQueries.generated.hbm.xml"
    },
    {
      "Name": "EntityOrmMappings",
      "Driver": "EntityOrmMappingsForViews",
      "OutputName": "EntityOrmMappingsForViews.generated.hbm.xml",
      "OutputPath": "EntityOrmMappingsForViews.generated.hbm.xml"
    }
  ],
  "standard.security": [
    {
      "Name": "EntityAuthorizationContextProviders",
      "Driver": "EntityAuthorizationContextProviders",
      "OutputName": "EntityAuthorizationContextProviders.generated.cs",
      "OutputPath": "Authorization\\EntityAuthorizationContextProviders.generated.cs"
    }
  ],
  "standard.xmlmetadata": [
    {
      "Name": "ContextMetadata",
      "Driver": "ContextMetadata",
      "OutputName": "ContextMetadata.generated.cs",
      "OutputPath": "XmlMetadata\\ContextMetadata.generated.cs"
    },
    {
      "Name": "EdOrgReferenceDictionaryProvider",
      "Driver": "EdOrgReferenceDictionaryProvider",
      "OutputName": "EdOrgReferenceDictionaryProvider.generated.cs",
      "OutputPath": "XmlMetadata\\EdOrgReferenceDictionaryProvider.generated.cs"
    },
    {
      "Name": "ElementsSchema",
      "Driver": "ElementsSchema",
      "OutputName": "Elements.schema.generated.cs",
      "OutputPath": "XmlMetadata\\Elements.schema.generated.cs"
    },
    {
      "Name": "NoForeignKeyMetadata",
      "Driver": "NoForeignKeyMetadata",
      "OutputName": "NoForeignKeyMetadata.generated.cs",
      "OutputPath": "XmlMetadata\\NoForeignKeyMetadata.generated.cs"
    }
  ],
  "database": [
    {
      "Name": "ResourceClaimMetadata",
      "Driver": "ResourceClaimMetadata",
      "OutputName": "0001-ResouceClaimMetadata_generated.sql",
      "OutputPath": "Data\\EdFiSecurity\\0001-ResouceClaimMetadata_generated.sql"
    }
  ],
  "profile": [
    {
      "Name": "Controllers",
      "Driver": "Controllers",
      "OutputName": "Controllers.generated.cs",
      "OutputPath": "Controllers\\Controllers.generated.cs"
    },
    {
      "Name": "CreateOrUpdatePipelines",
      "Driver": "CreateOrUpdatePipelines",
      "OutputName": "CreateOrUpdatePipelines.generated.cs",
      "OutputPath": "Pipelines\\CreateOrUpdatePipelines.generated.cs"
    },
    {
      "Name": "Requests",
      "Driver": "Requests",
      "OutputName": "Requests.generated.cs",
      "OutputPath": "Requests\\Requests.generated.cs"
    },
    {
      "Name": "Resources",
      "Driver": "Resources",
      "OutputName": "Resources.generated.cs",
      "OutputPath": "Resources\\Resources.generated.cs"
    }
  ],
  "extension": [
    {
      "Name": "EntityAuthorizationContextProviders",
      "Driver": "EntityAuthorizationContextProviders",
      "OutputName": "EntityAuthorizationContextProviders.generated.cs",
      "OutputPath": "Authorization\\EntityAuthorizationContextProviders.generated.cs"
    },
    {
      "Name": "InterchangeType",
      "Driver": "InterchangeType",
      "OutputName": "InterchangeType.generated.cs",
      "OutputPath": "BulkLoad\\InterchangeType.generated.cs"
    },
    {
      "Name": "AggregateLoaders",
      "Driver": "AggregateLoaders",
      "OutputName": "AggregateLoaders.generated.cs",
      "OutputPath": "BulkLoad\\Controllers\\Aggregates\\AggregateLoaders.generated.cs"
    },
    {
      "Name": "LoaderCollection",
      "Driver": "LoaderCollection",
      "OutputName": "LoaderCollection.generated.cs",
      "OutputPath": "BulkLoad\\Controllers\\Aggregates\\LoaderCollection.generated.cs"
    },
    {
      "Name": "EntityOrmMappings",
      "Driver": "EntityOrmMappings",
      "OutputName": "EntityOrmMappings.generated.hbm.xml",
      "OutputPath": "EntityOrmMappings\\EntityOrmMappings.generated.hbm.xml"
    },
    {
      "Name": "DatabaseMetadata",
      "Driver": "DatabaseMetadataProvider",
      "OutputName": "DatabaseMetadata.generated.cs",
      "OutputPath": "ExceptionHandling\\DatabaseMetadata.generated.cs"
    },
    {
      "Name": "Entities",
      "Driver": "Entities",
      "OutputName": "Entities.generated.cs",
      "OutputPath": "Models\\Entities\\Entities.generated.cs"
    },
    {
      "Name": "EntitiesForQueries",
      "Driver": "EntitiesForQueries",
      "OutputName": "EntitiesForQueries.generated.cs",
      "OutputPath": "Models\\Entities\\EntitiesForQueries.generated.cs"
    },
    {
      "Name": "EntitiesForQueriesViews",
      "Driver": "EntitiesForQueriesViews",
      "OutputName": "EntitiesForQueriesViews.generated.cs",
      "OutputPath": "Models\\Entities\\EntitiesForQueriesViews.generated.cs"
    },
    {
      "Name": "EntityInterfaces",
      "Driver": "EntityInterfaces",
      "OutputName": "EntityInterfaces.generated.cs",
      "OutputPath": "Models\\Interfaces\\EntityInterfaces.generated.cs"
    },
    {
      "Name": "EntityRecordInterfaces",
      "Driver": "EntityRecordInterfaces",
      "OutputName": "EntityRecordInterfaces.generated.cs",
      "OutputPath": "Models\\Interfaces\\EntityRecordInterfaces.generated.cs"
    },
    {
      "Name": "EntityMapper",
      "Driver": "EntityMapper",
      "OutputName": "EntityMapper.generated.cs",
      "OutputPath": "Models\\Mappers\\EntityMapper.generated.cs"
    },
    {
      "Name": "CreateOrUpdatePipelines",
      "Driver": "CreateOrUpdatePipelines",
      "OutputName": "CreateOrUpdatePipelines.generated.cs",
      "OutputPath": "Pipelines\\CreateOrUpdatePipelines.generated.cs"
    },
    {
      "Name": "Controllers",
      "Driver": "Controllers",
      "OutputName": "Controllers.generated.cs",
      "OutputPath": "Controllers\\Controllers.generated.cs"
    },
    {
      "Name": "Requests",
      "Driver": "Requests",
      "OutputName": "Requests.generated.cs",
      "OutputPath": "Requests\\Requests.generated.cs"
    },
    {
      "Name": "Resources",
      "Driver": "Resources",
      "OutputName": "Resources.generated.cs",
      "OutputPath": "Resources\\Resources.generated.cs"
    },
    {
      "Name": "ResourceFactories",
      "Driver": "ResourceFactories",
      "OutputName": "ResourceFactories.generated.cs",
      "OutputPath": "XmlShredding\\ResourceFactories.generated.cs"
    }
  ]
}

Command Line Parameters

The tool accepts the following command line argument:

  • -r <repository path>. The repository path to the location of the solution (e.g., C:\EdFi\v3).

Building Code Generation

The solution can be built using Visual Studio 2022 or Rider 2021.3. Also, it can be built from the command line using the following command: dotnet build.

Running Tests

Tests can be run using Visual Studio Test Explorer, R# Test Runner of Rider 2021.3. Alternatively, the tests can be run using the command dotnet test.

Running Approval Tests

Included in the testing suite are approval tests that validate the code generated is as expected.

To run the tests, the following steps are required:

Step 1 : Build the solution with Visual Studio.

Step 2 : Set EdFi.Ods.Codegen as the startup project. Note that the command argument is not necessary.

Step 3 : Run the solution within Visual Studio.

Step 4 : Open Test Explorer and look for the Verify_All test and run it to see if there are any failures

Step 5 : Approve any changes, if appropriate.