Geco, (Ge)nerator (Co)nsole

Simple code generator based on a console project, running on .Net Core and using C# interpolated strings.

Geco runs on .Net Core 2.0. Download and Install

What's the reasoning behind this utility?

One of the most popular code generation tools for Visual Studio over the years was T4 (Text Template Transformation Toolkit), which saw a great deal of success for simple to complex code generation tasks. Scott Hanselman has a nice blog post about it. However, since the advent of .Net Core and .Net going cross platform there is no simple way to generate code or other artifacts that would also work in Visual Studio Code (or other code editors).

This is where the idea for this simple utility came from. Have a small utility for code generation that is debuggable (one of the long standing issues of T4), provides some level of intellisense, can be run at build time, is higly customizable, generic and has an as small as possible footprint.

Installation

Geco can be installed as a Visual Studio Project Template or as dotnet new template.

To install Geco as a dotnet new template run the following command on a console or terminal:

dotnet new -i iQuarc.Geco.CSharp

Then create a new project using the newly installed template:

dotnet new geco

To create a Geco project when installed as a Visual Studio Project template, Select File -> New project select the Geco template.

Code Generation examples

Bellow are some snippets from the included code generation tasks that are in the default Geco package.

Next snippet is from the included Entity Framework Core Reverse model generator, which exemplifies part of the code generation:

This snippet is from the SQL Seed Scrip Generator, which generates SQL Merge scripts for Seed data:

Next screen shot shows Geco running in interactive mode (as a Console App), and the menu that is presented to the user:

Description

Geco uses C# 6.0 string interpolation as a template engine for code generation, in order to allow:

Easy customization of templates (Simply edit the .cs file)
Easy debugging (Place a breakpoint an run)
Easy extensibility (Add a new task by creating a new C# class and implement a simple interface IRunnable)

Geco uses task discovery at runtime and each task is configured using Dependency Injection. The generation tasks can be run during build or from interactive mode (Debug Run).

Included generators

The following generator tasks are included in current version.

Entity Framework Core 1.1, 2.0 Reverse model generator
SQL Seed data script generator (Generates MERGE scripts)
SQL Script runner
Database cleaner

Customizing

The first customization option involves changing task parameters from appsettings.json configuration file. Each Geco task defines its own set of parameters (see the corresponding Options class):

{
    "ConnectionStrings": {
        "DefaultConnection": "Integrated Security=True;Initial Catalog=AdventureWorks;Data Source=.\\SQLEXPRESS;"
    },
    "RunAtBuildTasks": [
        "Generate EF Core model"
    ],
    "Tasks": [
        {
            "Name": "Generate EF Core model",
            "TaskClass": "Geco.Database.EntityFrameworkCoreReverseModelGenerator",
            "BaseOutputPath": "..\\..\\Generated\\Model\\",
            "OutputToConsole": "false",
            "CleanFilesPattern": "*.cs",
            "Options": {
                "ConnectionName": "DefaultConnection",
                "Namespace": "Model",
                "OneFilePerEntity": true,
                "JsonSerialization": true,
                "GenerateComments": true,
                "UseSqlServer": true,
                "ConfigureWarnings": true,
                "GeneratedCodeAttribute": false,
                "NetCore": true,
                "ContextName":"AdventureworksContext"
            }
        }
    ]
}

By customizing existing templates directly.
By creating new code generation tasks as a C# class which implements the IRunnable interface.

IRunnable is a single method interface containing the Run method:

   /// <summary>
   /// Represents a runable task, for code generation or purposes or others
   /// </summary>
   public interface IRunnable
   {
       /// <summary>
       /// Invoked when this task is executed
       /// </summary>
       void Run();
   }

or by deriving from one of the helper base classes BaseGenerator or BaseGeneratorWithMetadata.

A code generation class can be accompanied by an Options POCO class to hold customization parameters from appsettings.json

Example:

    public class SeedDataGeneratorOptions
    {
        public string ConnectionName { get; set; }
        public string OutputFileName { get; set; }
        public List<string> Tables { get; } = new List<string>();
        public string TablesRegex { get; set; }
        public List<string> ExcludedTables { get; } = new List<string>();
        public string ExcludedTablesRegex { get; set; }
        public int ItemsPerStatement { get; set; } = 1000;
    }
        /// <summary>
    /// Generates seed scripts with merge statements for (Sql Server)
    /// </summary>
    [Options(typeof(SeedDataGeneratorOptions))]
    public class SeedDataGenerator : BaseGeneratorWithMetadata
    {
    // ...
    }

Roadmap

ASP.Net MVC Template (scaffolds controllers and views)
ASP.Net + Angular scaffolder (scaffolds Web Api and components)
SQL Sever to SQL Compact data sync template (Api to syncrhonize schema compatible SQL Server and SQL Compact databases including Web Api and .Net client methods)

Version History

Version 1.0.2

Added constraint delete behavior support
Modified logo

Version 1.0.1

Changed Entity Framework Core generator to allow multi column foreign keys
Fixed MetaData for MaxLength nvarchar and nchar columns
Removed tables without primary key from generated model
Switched to semver

Version 1.0.0.2

Changed user confirmation mechanism
Added user confirmation for file cleaning
Added more options for color output to console, formattable strings with tuple (value, ConsoleColor) parameters

Version 1.0.0.1

First release as a nuget dotnet new template

Version 1.0.0.0-beta

Initial Version
Contains code generation core functionality and SimpleMetadata model for databases

zanetdev/Geco