trex.kind.add-field

Add a Field to an Existing Kind

Add a new field to an existing Kind, updating all layers consistently.

Instructions

Ask the user for:

1. Kind name (PascalCase): e.g., "Dinosaur"
2. Field name (snake_case): e.g., "habitat_type"
3. Field type: string, int, int64, bool, float64, time.Time
4. Required or nullable: required fields use base types (string), nullable use pointers (*string)

Derive the Go field name in PascalCase (e.g., habitat_type -> HabitatType).

Use the TodoWrite tool to track progress.

Step 1: Update API Model (pkg/api/{kind}.go)

Add the field to the {Kind} struct:

HabitatType string `json:"habitat_type"`

Add the field to {Kind}PatchRequest as a pointer:

HabitatType *string `json:"habitat_type,omitempty"`

Step 2: Create a New Migration File

IMPORTANT: Create a brand new migration file at pkg/db/migrations/{YYYYMMDDHHMM}_add_{field}_to_{kindLowerPlural}.go. Do NOT modify the Kind's existing migration.

package migrations

import (
    "gorm.io/gorm"
    "github.com/go-gormigrate/gormigrate/v2"
)

func add{FieldPascalCase}To{KindPlural}() *gormigrate.Migration {
    type {Kind} struct {
        Model
        {FieldPascalCase} {GoType}
    }

    return &gormigrate.Migration{
        ID: "{YYYYMMDDHHMM}",
        Migrate: func(tx *gorm.DB) error {
            return tx.AutoMigrate(&{Kind}{})
        },
        Rollback: func(tx *gorm.DB) error {
            return tx.Migrator().DropColumn(&{Kind}{}, "{field_snake_case}")
        },
    }
}

Register it in pkg/db/migrations/migration_structs.go by appending to MigrationList.

Step 3: Update Presenter (pkg/api/presenters/{kind}.go)

Add the field to both Convert{Kind}() and Present{Kind}() functions, handling the type conversion between internal and OpenAPI models.

Step 4: Update Handler (pkg/handlers/{kind}.go)

In the Patch method, add the nil-check for the new field:

if patch.{FieldPascalCase} != nil {
    found.{FieldPascalCase} = patch.{FieldPascalCase}
}