Migration Guide

Sannr includes a powerful CLI tool to help migrate from other validation libraries like FluentValidation and DataAnnotations.

Installation

The migration CLI is included when you install Sannr:

dotnet add package Sannr

Analyze Your Project

First, analyze your existing validation code to understand migration complexity:

# Analyze a directory for validation patterns
dotnet run --project Sannr.Cli -- analyze --input ./MyProject/Models

# Output example:
  Analysis Results:
 Files scanned: 15
   Validation libraries detected: FluentValidation, DataAnnotations
  FluentValidation rules found: 23
  DataAnnotations found: 45
  Migration Complexity: Medium
  Recommendation: Moderate complexity - review generated code carefully

Migrate from DataAnnotations

Convert DataAnnotations attributes to Sannr (automatic conversion):

# Migrate DataAnnotations in-place
dotnet run --project Sannr.Cli -- dataannotations --input ./Models --output ./Models

# Or migrate to a new directory
dotnet run --project Sannr.Cli -- dataannotations --input ./OldModels --output ./NewModels

What gets converted:

• [Required] -> [Required] (Sannr equivalent)
• [EmailAddress] -> [Email] (Sannr naming)
• [StringLength(50)] -> [StringLength(50)] (compatible)
• [MaxLength(100)] -> [StringLength(100)] (converted)
• Adds using Sannr; directive

Migrate from FluentValidation

Get guidance for converting FluentValidation validators:

# Analyze FluentValidation code
dotnet run --project Sannr.Cli -- fluentvalidation --input ./Validators --dry-run

Generated guidance includes:

• Comments showing original FluentValidation rules
• TODO items for manual conversion steps
• Migration notes and best practices

Migration Examples

Before (FluentValidation):

public class UserValidator : AbstractValidator<User>
{
    public UserValidator()
    {
        RuleFor(x => x.Name).NotEmpty().Length(2, 50);
        RuleFor(x => x.Email).NotEmpty().EmailAddress();
    }
}

After (Sannr with guidance):

using Sannr;

// TODO: Convert to Sannr attributes on model properties
// Original FluentValidation: RuleFor(x => x.Name).NotEmpty().Length(2, 50);
/*
 * MIGRATION NOTES:
 * 1. Move validation rules from validator classes to model properties as attributes
 * 2. Remove this validator class after migrating all rules
 */

CLI Options

# Analyze validation code
dotnet run --project Sannr.Cli -- analyze --input <path> [--type auto|fluentvalidation|dataannotations]

# Migrate DataAnnotations
dotnet run --project Sannr.Cli -- dataannotations --input <path> --output <path> [--overwrite] [--dry-run]