anetos gen reference

anetos gen writes the typed columns of your models. It is part of the anetos developer tool (module anetos.dev/anetos/cli). See Generate typed columns for a walkthrough.

Installing and running

Package patterns are the ones go build takes. Exit status: 0 on success, 1 on errors (or out-of-date files with -check), 2 for bad usage.

Which structs are models

A named, non-generic struct type declared at package level (in a non-test file) is a model when it:

Models, and the structs of their package they embed, must be in files without build constraints (no //go:build line, no _linux.go-style name), so the generated file is the same on every platform. //anetos:skip in the doc comment excludes a struct. Any other //anetos: directive is an error. Structs that scan themselves (sql.Scanner, driver.Valuer, time.Time) are values, not models.

What is generated

One file per package, models_gen.go, starting with // Code generated by anetos gen. DO NOT EDIT. For each model Name in source order:

// illustrative
// NameCols are the columns of [Name].
var NameCols = struct {
	Field db.Column[FieldType]
	…
}{
	Field: db.Col[FieldType]("column"),
	…
}

The column rules are the db package’s (models reference). The generated names are the struct field names; an unexported model post gets postCols. Imports get another name (time2) when the package already declares that name in any of its files (in-package tests and other platforms’ files included).

Files it manages

• It only overwrites or removes a models_gen.go that starts with its header (Unix or Windows line endings); any other file with that name is an error, even one excluded from the build.
• It removes models_gen.go from a package with no models left.
• It ignores the current models_gen.go while reading the package, and compile errors outside model fields (such as code using a column not generated yet). Syntax errors, and type errors in a model’s fields, stop it.
• Packages are only type-checked when they import the db package (directly or not), mention TableName or a //anetos: directive, or already have a models_gen.go.

Errors