Go macro

A go tool to analyze your code and generate boilerplate in various formats

This module provides a tool taking Go code as input and generating boilerplate code in the following languages :

• Go : JSON support for union types (generator/go/unions), SQL CRUD operations (generator/go/sqlcrud) and random data structure generation (generator/go/randdata).
• SQL (Postgres) : creation statements and JSON validation functions (generator/sql)
• TypeScript : type definitions and Axios API (generator/typescript)
• Dart : type definitions and JSON routines (generator/dart)

CLI usage

Single file mode

Provide a go source file as input, followed by the desired generation mode in the form <action>:<outputile>. Several actions may be specified.

./gomacro myinput.go sql:ouput.sql

Module overview

analysis

This package provides an extension of the standard go/types package with support for enums, union types and time and date. It knows nothing about the output targets, but serves as a shared base.

Package analysis/httpapi provides a scanner to extract API urls and types. It only supports the Echo framework, but is modular, so that adding support for other frameworks should be quick.

Package analysis/sql adds a convertor from Go types to SQL ones and some logic about table relations.

generator

This package uses the result provided by analysis to actually generate the code.

The generator/typescript package only targets the Axios Javascript library, but the TypeScript types generator could be easily reused to support other methods.

Code directives and conventions

This module tries to be as smart and general as possible, but relies on special comments when desambiguation is required.

• The following struct fields are ignored:
  • unexported
  • with a 'json' tag '-'
  • with a 'gomacro' tag 'ignore'
• Definition of a constant which is not an enumeration: add // gomacro:no-enum
• Rely on an external generated file: add the gomacro-extern:"<pkg>:<mode1>:<targetFile1>:<mode2>:<targetFile2>" tag to struct fields
• Types with name containing "Date" and with underlying time.Time are considered as date
• Struct fields with gomacro-data:"ignore" are ignored from random data generation.
• SQL foreign keys are detected with types following the ID convention or tagged with gomacro-sql-foreign:"<table>", and an implicit constraint is generated. The gomacro-sql-on-delete:"<action>" may be provided to add for instance a cascade.
• Custom SQL constraints may be provided with struct comments of the form // gomacro:SQL <constraint>. The constraint is always prefixed by ALTER TABLE <table>. The Go struct names are replaced by their appropriate SQL equivalents. Enum value may be used inside comments with the syntax #[<TypeName>.<EnumConstant>].