CLI reference

Installation

Use Go’s tool directive to pin the generator version in go.mod:

go get -tool github.com/tylergannon/go-gen-jsonschema/gen-jsonschema@latest

Invoke the pinned CLI as go tool gen-jsonschema.

Generate

go tool gen-jsonschema
go tool gen-jsonschema gen [flags]
  -pretty            indent schema JSON
  -target DIR        package to process (default: current directory)
  -no-changes        fail without writing schemas when schema JSON would change
  -force             rewrite unchanged output; incompatible with -no-changes
  -num-test-samples N  accepted for compatibility; currently has no effect
  --validate         generate ValidateJSON methods

The command without a subcommand is equivalent to gen.

Scaffold a registration file

go tool gen-jsonschema new [flags]
  -out FILE          output path; empty or -- writes to stdout
  -pkg NAME          package name override for stdout mode
  -methods LIST      required comma-separated Type=Method entries
  --validate         include ValidateJSON stubs
  --generate         run go generate ./... after writing

Example:

go tool gen-jsonschema new \
  -out schema.go \
  -methods 'Person=Schema,Address=Schema' \
  --validate \
  --generate

Environment

Any non-empty JSONSCHEMA_NO_CHANGES value is equivalent to -no-changes and applies through existing go generate directives. It guards schema JSON, but generation can still update jsonschema_gen.go when schemas are unchanged. In CI, follow generation with test -z "$(git status --porcelain)" to verify tracked and untracked generated files.